CP15 SEMESTER 5

Prepared by: Mr. Enoch N [DTC] & Mr. Shiju G [NEC] Verified by: Mr. Surendhar Kumar K Approved by: Mr. Shankar G Rev No : 01 Released Date : 01/09/2021

CP15 SEMESTER 5 Embedded Systems & IOT

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Go to Table of Content NTTF_CP15 _DIPLOMA IN MECHATRONICS ENGINEERING & SMART FACTORY _SEM 5_EMBEDDED SYSTEMS & IOT_COURSE CONTENT 1

Contents 1.0 EMBEDDED SYSTEM ...................................................................................................................................... 2

1.1 Introduction, Categories, Applications, Specialities of Embedded system ........................................................... 2

1.2 Overview of Embedded System Architecture ....................................................................................................... 9

1.3 Special Features: Power on reset feature, Watch dog timer, SLEEP mode, Interrupt handling capability. ....... 12

2.0 PERIPHERAL INTERFACE CONTROLLER – PIC16F877A .................................................................................... 18

2.1 Introduction to PIC Microcontroller .................................................................................................................... 18

2.2 Features of PIC16F877 ......................................................................................................................................... 19

2.3 Architecture of PIC 16F877A ............................................................................................................................... 21

2.4 Memory organization .......................................................................................................................................... 26

2.5 Pin Diagram ......................................................................................................................................................... 34

2.6 Input/Output Ports ............................................................................................................................................. 38

2.7. Timers ................................................................................................................................................................. 41

3.0 NODE MCU - ESP8266 ................................................................................................................................. 54

3.1 Introduction to Node MCU and Its Features. ...................................................................................................... 54

3.2 Pin configuration of NODE MCU. ........................................................................................................................ 56

4.0 NODE MCU AND ARDUINO PROGRAMMING ................................................................................................ 59

4.1 Introduction to Arduino and Its Features ............................................................................................................ 59

4.2 Variables, Data Types & Constants...................................................................................................................... 63

4.3 Programming Structure ....................................................................................................................................... 68

4.4 Digital I/O Programming ...................................................................................................................................... 69

4.5 Analog I/O Programming ..................................................................................................................................... 73

4.6 Serial Data Monitoring ........................................................................................................................................ 77

5.0 IoT (Internet of Things)................................................................................................................................ 80

5.1 Internet of Things (IoT) ........................................................................................................................................ 80

5.2 Components of IoT .............................................................................................................................................. 84

5.3 Four Stages of IoT Architecture ........................................................................................................................... 89

5.4 Architecture of IoT............................................................................................................................................... 92

5.5 Industrial IoT – Process, Advantages & Applications ........................................................................................ 101

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1.0 EMBEDDED SYSTEM

1.1 Introduction, Categories, Applications, Specialities of Embedded system

Introduction

An Embedded Systems are computing devices that do a specific focused job. An

embedded system is a microprocessor- or microcontroller-based system of hardware and

software designed to perform dedicated functions within a larger mechanical or

electrical system.

Embedded systems are computing systems with tightly coupled hardware and

software integration, that are

designed to perform a dedicated

function.

The word embedded reflects

the fact that these systems are

usually an integral part of a larger

system. Multiple embedded

systems can coexist in an large

functional system.

Appliances such as Air

conditioners, DVD players, fax

machines, printers, mobile phones

etc, are examples of Embedded

Systems.

Embedded systems are characterized by some special features as listed below

They are task specific. They do the same task repeatedly /continuously over their lifetime. An mp3 player will function only as an mp3 player.

Embedded systems have very limited resources.

They are created to perform the task within a certain time frame. It must therefore

perform fast enough. A car’s brake system, if exceeds the time limit, may cause

accidents.

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They have minimal or no user interface (UI). A fully automatic washing machine works on its own after the programme is set and stops once the task is over.

Embedded systems are built to achieve certain efficiency levels. They are small sized, can work with less power.

Embedded systems cannot be changed or upgraded by the users. Hence, they must very reliable and stable. They are expected to function for long durations without the user experiencing any difficulties. For example refrigerator.

Categories of Embedded Systems

Embedde systems are categorized

based on :

a. Performance and functional

requirements.

b. Performance of microcontroller.

We will limit our discussion to types of

embedded systems based on functional

requirements.

1. Stand-alone embedded systems: As the name implies, stand-alone systems

work in stand-alone mode. They take inputs, process them and produce the desired

output. The input can be electrical signals from transducers or command from a human

being such as the pressing of a button. The output can be electrical signals to drive

another system, an LED display or LCD display for displaying of information to the users.

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Embedded systems used in process control, automobiles, consumer electronic items etc.

fall into this category. In a process control system, the inputs are from sensors that convert

a physical entity such as temperature or pressure into its equivalent electrical signal. These

electrical signals are processed by the system and the appropriate electrical signals are

produced using which an action is taken such as opening a valve.

Some more examples: Microwave ovens, Digital cameras, Mp3 players, Video game consoles, Temperature measurement systems.

2. Real - time systems: Embedded systems in which some specific work has to be done

in a specific time period are called Real time systems. Real-time embedded systems have

to complete a specific task in a specified time period. Meeting the deadlines is the most

important requirement of real-time systems. To develop the real-time embedded system

we require timing analysis, multitasking design, debugging, cross-platform testing and

architecture design. In these systems, quick response is very important.

For example, consider a system that has to open a valve within 30 milliseconds

when the humidity crosses a particular threshold. If the valve is not opened within 30

milliseconds, the equipment may get damaged.

Examples : Controlling heat, elevators, lights, and doors in buildings Robots Traffic control system including railway tracks, airspace, shipping lines Radio, satellite and telephone communication Patient monitoring system Radiation therapy system in the hospital Computer games Multimedia systems consisting of video, audio, text and graphics interfaces Military usage that includes tracking, weapons, and command & control

Real-time systems are categorized as

a. Hard real-time systems.

b. Soft real-time systems.

a. Hard real-time systems: In hard real-time

systems, missing a deadline may lead to a

catastrophe.

A missile that has to track and intercept an

enemy aircraft. The missile contains an embedded system that tracks the aircraft and

generates a control signal that will launch the missile. If there is a delay in tracking the

aircraft and if the missile misses the deadline, the enemy aircraft may drop a bomb and

cause loss of many lives. Hence, this system is a hard real-time embedded system.

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b. Soft real-time systems: In soft real-time systems,

meeting the deadline is important but missing the

deadline will not lead to a catastrophe. In some

embedded systems, deadlines are imposed, bur not

adhering to them once in a while may not lead to

catastrophe.

For example, consider a DVD player. Suppose, you give a command to the DVD

player from a remote control, and there is a delay of a few milliseconds in executing that

command. But this delay won't lead to a serious implication. Such systems are called soft

real-time systems.

3. Networked information appliances: Embedded systems that are provided with

network interfaces and accessed through networks such as Local Area Network or the

Internet are called networked information appliances. Such embedded systems are

connected to a network, typically using TCP/IP (Transmission Control Protocol/ Internet

Protocol) protocol, such as the Internet or a Intranet. These systems have emerged in

recent years.

These systems communicate with other nodes in the network.

Example 1: A networked process control system consists of a number of embedded

systems connected as a Local Area Network. Each embedded system can send real-time

data to a central location from where the entire process control system can be monitored.

The monitoring can be done using a web browser such as the Internet Explorer

Example 2: A web camera can be connected to the Internet. The web camera send

pictures in real-time to any computer connected to the internet. In such a case, the web

camera has to run the HTTP server software in addition to the TCP/IP protocol stack.

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Example 3: The door-lock of your home can be a small embedded system with TCP/IP and

HTTP server software running on it. When your children stand in front of the door-lock

after they return from school, the web camera in the door-lock will send an alert to your

desktop over the Internet and then you can open the door-lock through a click of the

mouse.

4. Mobile Devices: Mobile devices such as mobile

phones, Personal Digital Assistants (PDAs), smart phones

etc. are special category of embedded systems. Though the

PDAs do many general-purpose tasks, they need to be

designed just like the 'conventional' embedded systems.

The limitations of the mobile devices are memory

constraints, small size, lack of good user interfaces. Hence,

mobile devices are considered as embedded systems. However, the PDAs are now capable

of supporting general-purpose application software such as word processors, games, etc.

Application Areas

Nearly 99% of the processors manufactured end up in embedded systems. The embedded

system market is one of the highest growth areas as these systems are used in very market

segments like consumer electronics, office automation, industrial automation, biomedical

engineering. wireless communication, data communication, telecommunications,

transportation, military and so on.

Consumer appliances: At home we use a number of

embedded systems which include digital camera,

digital diary, DVD player, electronic toys, microwave

oven, remote controls for TV and air-conditioner, VCD

player, video game consoles, video recorders etc.

Industrial automation: Today a lot of industries

use embedded systems for process control. These

include pharmaceutical, cement, sugar, oil

exploration, nuclear energy, electricity generation

and transmission. The embedded systems for

industrial use are designed to carry out specific

tasks such as monitoring the temperature,

pressure, humidity, voltage, current etc.

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Wireless technologies: Advances in mobile

communications are paving way for many interesting

applications using embedded systems. The mobile phone is

one of the marvels of the last decade of the 20h century. lt

is a very powerful embedded system that provides voice

communication while we are on the move. The Personal

Digital Assistants and the palmtops can now be used to

access multimedia services over the Internet.

Office automation: The office automation products

using embedded systems are copying machine, fax

machine, key telephone, modem, printer, scanner etc.

Instrumentation: Testing and measurement are the

fundamental requirements in all scientific and engineering

activities. The measuring equipment we use in laboratories

to measure parameters such as weight, temperature,

pressure, humidity, voltage, current etc. are all embedded

systems.

Security: Security of persons and information has always

been a major issue. We need to protect our homes and

offices; and also, the information we transmit and store.

Developing embedded systems for security applications is

one of the most lucrative businesses nowadays. Security

devices at offices, airports etc. for authentication and

verification are embedded systems.

Finance: Financial dealing through cash and cheques are now

slowly paving way for transactions using smart cards and ATM

(Automatic Teller Machine) machines. Smart card, of the size

of a credit card, has a small micro-controller and memory; and

it interacts with the smart card reader/ATM machine and acts

as' an electronic wallet. Smart card technology has the

capability of ushering in a cashless society.

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Medical electronics: Almost every medical equipment in

the hospital is an embedded system. These equipment's

include diagnostic aids such as ECG, EEG, blood pressure

measuring devices, X-ray Scanners equipment used in

blood analysis, radiation, colonoscopy, endoscopy etc.

Telecommunications: In the field of telecommunications, the embedded systems can be

categorized as subscriber terminals and network equipment. The subscriber terminals such

as key telephones, ISDN phones, terminal adapters, web cameras are embedded systems

Computer networking: Computer networking products such as bridges, routers,

Integrated Services Digital Networks (ISDN), Asynchronous Transfer Mode (ATM), and

frame relay switches are embedded systems which implement the necessary data

communication protocols.

Specialities of Embedded Systems

Performance: Many embedded systems have time constraints.

For instance, in a process control system, a constraint can be: "if the temperature exceeds

40 degrees, open a valve within 10 milliseconds." The system must meet such deadlines.

If the deadlines are missed, it may result in a catastrophe.

You can imagine the damage that can be done if such deadlines are not met in a safety

system of a nuclear plant.

Power Consumption: Most of the embedded systems operate through a battery. To

reduce the battery drain and avoid frequent recharging of the battery, the power

consumption of the embedded system has to be very low.

Cost: For embedded systems used in safety applications of a nuclear plant or in a space

craft, cost may not be a very important factor. However, for embedded systems used in

consumer electronics or office automation, the cost is of utmost importance.

Size: Size is certainly a factor for many embedded systems. We do not like a mobile phone

that has to be carried on our backs. The size and the weight are important parameters in

embedded systems used in aircraft, spacecraft, missiles etc.

Limited User Interface: Unlike desktops, which have full-fledged input/output devices,

embedded systems do not have sophisticated interfaces for input and output. Some

embedded systems do not have any user interface at all. They take electrical signals as

input and produce electrical signals as output.

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Software Upgradation Capability: Embedded systems are meant for a very specific task.

So, once the software is transferred to the embedded system, the same software will run

throughout its life.) However, in some cases, it may be necessary to upgrade the software.

1.2 Overview of Embedded System Architecture

In a computer system, the operating system

runs above the hardware, and the application

software runs above the operating system. In case of

embedded systems, it is not compulsory to have an

operating system. For small appliances such as

remote-control units, air-conditioners, toys etc.,

there is no need for an operating system and you can

write only the software specific to that application.

A. Hardware architecture

Building Blocks of the Hardware in an Embedded

System

I/O Devices: Input and output devices allow the embedded system to interact with the

outside world by moving data into and out of the system. An input device is used to bring

data into the system.

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ADC & DAC: ADC conversion involves two steps Sampling and Quantization. The analog

signal sampled at regular interval and the sampled values are rounded off to fixed number

of levels called quantization levels. These quantization values are converted into bit

stream.

Power Supply Unit: The power supply unit is used to provide a stable DC voltage for the

embedded systems. Some embedded systems use batteries as power source.

Clock Circuitory: The processor has to be given the clock input to one of the pins. All

processor events are related to the clock .The higher the clock frequency the higher the

speed.

Chip Select: Many peripheral share a common bus .The process must be able to uniquely

identify a peripheral to communicate with it. The processor performs this identification

using a signal called chip select. The select signal is available to all the peripheral

connected to the bus.

Watch Dog Timer: Watch dog timer is used to reset the processor automatically. It does

not receive a signal periodically from the processor indicating its heating status. This

mechanism obviates the need for a rest button on the embedded system.

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Communication Interface: The communication channel which interconnects the various

components within an embedded product is referred as communication interface.

Examples – Serial interfaces like I2C,I-Wire, and parallel bus interface.

Timers: A timer is a specialized type of clock which is used to measure time intervals. A

counter is a device that stores (and sometimes displays) the number of times a particular

event or process occurred, with respect to a clock signal.

Memory: The memory is categorized as Random Access Memory(RAM) and ROM. The

contents of RAM will be erased it power is switched off to the chip. Where as Rom retains

the contents even if the power is switched off. So the firm ware is stored in the ROM.

When the power is switched On , the processor read, ROM, the program is transferred to

the RAM and the program is executed.

B. Software architecture

The software in an embedded system consists of an operating system and the

application software. The operating system is optional; if it is not present, you need to

write your own software routines to access the hardware.

Categories of Embedded Operating Systems

a. Non-real-time Embedded Operating Systems.

b. Real-time Operating Systems.

c. Mobile/Handheld Operating Systems.

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Kernel: Kernel manages the tasks to achieve the

desired performance of the embedded system. To

manage the tasks, the important requirements are

to schedule the tasks and to provide inter-task

communication facilities

Device Manager: The I/O devices are used to

send/receive data from the embedded system. The

OS manages the I/O devices through interrupts and device drivers. Device drivers provide

the necessary interface between the application and the hardware.

Communication Protocol Software: If the embedded system has communication

interfaces such as Ethernet, USB etc., the-upper layer protocols such as TCP/IP stack need

to be integrated with the OS. Then the embedded system can be network-enabled.

Libraries: The operating system may have some C/C++ library files in object code, which

can be used through the API calls.

File System: Most of the embedded systems do not have a secondary storage. In such

cases, the ROM is used to store the program. In case a file system is required, a small file

system can be developed on flash memory. Some embedded systems may use a secondary

storage just for booting

1.3 Special Features: Power on reset feature, Watch dog timer, SLEEP mode, Interrupt handling capability.

Power On Reset: A power-on reset (PoR) is a circuit that provides a predictable,

regulated voltage to a microprocessor or

microcontroller with the initial application

of power. The PoR system ensures that the

microprocessor or microcontroller will start

in the same condition every time it is

powered up. A power-on-reset circuit is

responsible for generating resetting signals

whenever power is supplied to a given

electrical device. In such manner, you can

determine a known state in which the device always powers up or starts operating.

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A power on reset circuit ensures the

system power supply stabilizes at the

correct levels, the clocks of the processors

settle accurately, and that the loading of

the internal registers is complete before

the device actually starts working or gets

powered up. The time period of the reset

state is determined and measured using

the charging of a capacitor which is placed

in series with a resistor. When power is

applied, the current goes via the capacitor

and the voltage of capacitor increases

slowly. At the beginning, the voltage is lower than the reset input pin threshold voltage

and all elements in the CPU are hold in reset mode. And then, the voltage is higher than

that threshold voltage, the reset pin gets a “1” and the system initializes. The values of the

resistor and capacitor determine the power on reset latency.

A power on reset circuit also has good noise immunity which means that in the case that a

power supply suffers a minor glitch that passes by quickly enough

Watch Dog Timer: Sometimes a system goes into an infinite loop (hangs). A watchdog

timer is a specialized timer module that helps a microprocessor to recover from such

situations. It is a counter running

on its own. If a watchdog timer

reaches the end of its counting

period, it resets the entire

processor system. In order to

prevent this, a processor must

perform some type of specific

action that resets the watchdog.

Thus, a watchdog timer can be

configured such that it will reach

the end of its counting period

only if a processor failure has occurred, and by forcing a system reset, the watchdog timer

helps the processor to escape from the failure mode and continue normal operation.

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Microcontrollers are often used in harsh

environments where power supply

transients, electromagnetic interference

(EMI), and electrostatic discharge (ESD)

are abundant. Program corruption

caused by bus corruption and

electromagnetic discharges can cause a

microprocessor to execute erroneous

instructions. In these environments, a

watchdog timer is a useful peripheral that

can help catch and reset a microcontroller

that has gone "out of control."

The primary application of a

watchdog timer is as a system monitor to

detect and reset an "out of control"

microcontroller. When program execution

goes awry it will not properly execute the

code that restarts the watchdog. In such a

case the watchdog timer will timeout and

cause a microcontroller reset.

SLEEP mode: The term “sleep mode” (sometimes called “power down mode”) refers to a

condition in which an embedded system enters a low-power mode. Typically, the

microcontroller (MCU) ceases to perform any computations, although it will retain any

current data, and peripheral functions

will stop working.

In reality, the processor or

microcontroller will still continue to

run in sleep mode insofar as

maintaining its ability to wake up to

handle interrupts and real time tasks.

A common example of sleep mode is

used in our computers or laptops.

When you lock out your PC, the

system will go into sleep and suspend any unwanted tasks to save power.

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A wide range of embedded systems, such as smart phones, washing machines, and

ATMs, have the ability to run in a power-down state to use the CPU resources efficiently.

Sleep mode is often employed

by microcontrollers that need

the ability to wake up and

respond to unexpected events.

Sleep mode maybe referred to

as standby mode in some cases.

The primary task to achieve

standby mode is to power off

the peripheral blocks in microcontrollers. For instance, you can switch off the I/O

(input/output peripherals) to reduce power consumption.

Interrupt Handling Capability: An interrupt is a signal to the processor emitted by

hardware or software indicating an event that needs immediate attention. Whenever an

interrupt occurs, the controller completes the execution of the current instruction and

starts the execution of an Interrupt Service Routine (ISR) or Interrupt Handler. ISR tells the

processor or controller what to do when the interrupt occurs. The interrupts can be either

hardware interrupts or software interrupts.

a. Hardware Interrupt: A hardware interrupt is an electronic alerting signal sent to the processor from an external device, like a disk controller or an external peripheral. For example, when we press a key on the keyboard or move the mouse, they trigger hardware interrupts which cause the processor to read the keystroke or mouse position.

b. Software Interrupt: A software interrupt is caused either by an exceptional condition or a special instruction in the instruction set which causes an interrupt when it is executed by the processor. For example, if the processor's arithmetic logic unit runs a command to divide a number by zero, to cause a divide-by-zero exception, thus causing the computer to abandon the calculation or display an error message. Software interrupt instructions work similar to subroutine calls.

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Interrupt Service Routine: For every interrupt, there must be an interrupt service routine (ISR), or interrupt handler. When an interrupt occurs, the microcontroller runs the interrupt service routine. For every interrupt, there is a fixed location in memory that holds the address of its interrupt service routine, ISR. The table of memory locations set aside to hold the addresses of ISRs is called as the Interrupt Vector Table.

Steps to Execute an Interrupt

When an interrupt gets active, the microcontroller goes through the following steps −

• The microcontroller closes the currently executing instruction and saves the address

of the next instruction (PC) on the stack.

• It also saves the current status of all the interrupts internally (i.e., not on the stack).

• It jumps to the memory location of the interrupt vector table that holds the address

of the interrupts service routine.

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• The microcontroller gets the address of the ISR from the interrupt vector table and

jumps to it. It starts to execute the interrupt service subroutine, which is RETI

(return from interrupt).

• Upon executing the RETI instruction, the microcontroller returns to the location

where it was interrupted. First, it gets the program counter (PC) address from the

stack by popping the top bytes of the stack into the PC. Then, it starts to execute

from that address.

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2.0 PERIPHERAL INTERFACE CONTROLLER – PIC16F877A

2.1 Introduction to PIC Microcontroller

The PIC microcontroller PIC16f877A is one of the most renowned microcontrollers in the industry. This microcontroller is very convenient to use, the coding or programming of this controller is also easier. One of the main advantages is that it can be write-erase as many times as possible because it uses FLASH memory technology. It has a total number of 40 pins and there are 33 pins for input and output. PIC16F877A is used in many PIC microcontroller projects. PIC16F877A also have much application in digital electronics circuits.

PIC stands for Peripheral Interface Controller. PIC micro-controller was developed by Microchip. This micro-controller is a very fast simple micro-controller in implementation and performance point of view. This micro-controller is easy to program and also it easy to interface with other peripherals. Every PIC microcontroller architecture consists of some registers and stack where registers function as Random Access Memory (RAM) and stack saves the return addresses. The main features of PIC microcontrollers are RAM, flash memory, Timers/Counters, EEPROM, I/O Ports, USART, CCP (Capture/Compare/PWM module), SSP, Comparator, ADC (Analog to digital converter), PSP (parallel slave port), LCD and ICSP (in circuit serial programming) The 8-bit PIC microcontroller is classified into four types on the basis of internal architecture such as Base Line PIC, Mid-Range PIC, Enhanced Mid-Range PIC and PIC18. Why PIC PIC16F877A Microcontroller?

Availability of resource: When you start your project, after framing the working logic when you look for controllers you end up with 8051 or PIC. Again if you try to constrain you will end up with PIC.

Money: It is cheaper. You can get it for less than Rs.100. You can get 8051 controller also for less than Rs.100. Both are easily available in most of the electronics stores.

Architecture/PIN configuration: You can configure the functions of PIN based on your requirement.

Tool: This is one the most important fact. When you have an IC and you don’t have resource to program it, then it is waste buying at low cost. Both 8051 and PIC tools are easily available on the internet and also easy to use for the beginners.

Dumper kits: After programming in the tool, it is very important that we should be able to dimp the program into the IC. The dumper kits are easily available in market for these two.

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Knowledge: The knowledge transfer can be easily done for this. Either your senior or any professor will able to help you in this regard very easily with their past experience and your project can be completed easily.

Programming: Both these IC can be programmed in C language. Hence easy to program for the beginners.

8051 vs PIC: Most of the college projects are so simple and it does not need to worry about clock frequency, oscillator frequency, Data port width, number of ports, features like serial ports, interrupts, timers, memory etc. will make you choose between 8051 and PIC.

PIC16f877A finds its applications in a large number of devices. It is used in remote sensors, security and safety devices, home automation and many industrial instruments. An EEPROM is also featured in it, which makes it possible to store some of the information permanently like transmitter codes and receiver frequencies and some other related data. The cost of this controller is low and its handling is also easy. It is flexible and can be used in areas where microcontrollers have never been used before as in microprocessor applications and timer functions etc. Various types of microcontrollers exist, even though the best are found in the GENIE range of programmable microcontrollers. These microcontrollers are programmed and simulated by circuit-wizard software.

It has a 35 instructions set. It can operate up to 20MHz frequency. The operating voltage is between 4.2 volts to 5.5 volts. If you provide it voltage more

than 5.5 volts, it may get damaged permanently. It does not have an internal oscillator like other PIC18F46K22, PIC18F4550 series. The maximum current each PORT can sink or source is around 100mA. Therefore, the

current limit for each GPIO pin of PIC16F877A is 10mA. It is available in four IC packaging such as 40-pin PDIP 44-pin PLCC, 44-pin TQFP, 44-pin

QFN.

The PIC microcontroller architecture comprises of CPU, I/O ports, memory organization, A/D converter, timers/counters, interrupts, serial communication, oscillator and CCP module etc.

2.2 Features of PIC16F877

The PIC16FXX series has more advanced and developed features when compared to

its previous series. The important features of PIC16F877 series is given below.

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General Features

• High performance RISC CPU.

• ONLY 35 simple word instructions.

• All single cycle instructions except program branches which are of two cycles.

• Operating speed: clock input (200MHz), instruction cycle (200nS).

• Up to 368×8bit of RAM (data memory), 256×8bit of EEPROM (data memory), 8k×14bit of flash memory.

• Pin out compatible to PIC 16C74B, PIC 16C76, PIC 16C77.

• Eight level deep hardware stack (Up to 8 nesting subroutines).

• Interrupt capability (up to 14 sources).

• Different types of addressing modes (direct, Indirect, relative addressing modes).

• Power on Reset (POR). Power-Up Timer (PWRT) and oscillator start-up timer.

• Low power- high speed CMOS flash/EEPROM.

• Wide operating voltage range (2.0 – 5.56) volts.

• High sink/source current (25mA).

• Low power consumption (<0.6mA typical @3v-4MHz, 20µA typical @3v-32MHz and <1 A typical standby).

Peripheral Features

• Timer 0: 8-bit timer/counter with pre-scalar.

• Timer 1: 16-bit timer/counter with pre-scalar.

• Timer 2: 8-bit timer/counter with 8-bit period registers with pre-scalar and post-scalar.

• Two Capture (16bit/12.5nS), Compare (16 bit/200nS), Pulse Width Modules (10bit).

• 10bit multi-channel (8 channels) A/D converter

• Synchronous Serial Port (SSP) with SPI (master code) and I2C (master/slave).

• Universal Synchronous Asynchronous Receiver Transmitter (USART) with 9-bit address detection.

• Parallel Slave Port communication port (PSP) 8 bit wide with external RD, WR and CS controls (40/46pin).

• Brown Out circuitry for Brown-Out Reset (BOR).

• 5 input/output ports.

• 2 CCP (Capture/Compare/PWM) modules.

Special Features

• 1000000 times erase/write cycle data EEPROM memory.

• Self-programmable under software control.

• In-circuit serial programming and in-circuit debugging capability.

• Single 5V, DC supply for circuit serial programming

• WDT with its own RC oscillator for reliable operation.

• Programmable code protection.

• Power saving sleep modes.

• Selectable oscillator options.

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2.3 Architecture of PIC 16F877A

The basic building block of PIC 16F877A is based on Harvard architecture. Here you can see the basic internal architecture and memory organisation of PIC16F877A.

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The simplied version of the architecture

CPU The function of CPU in PIC is same as a normal microcontroller CPU. A PIC CPU consists

of several sub units such as instruction decoder, ALU, accumulator, control unit, etc. The CPU in PIC normally supports Reduced Instruction Set Computer (RISC) architecture (Reduced Instruction Set Computer (RISC), a type of microprocessor that focuses on rapid and efficient processing of a relatively small set of instructions. RISC design is based on the premise that most of the instructions a computer decodes and executes are simple. As a result, RISC architecture limits the number of instructions that are built into the microcontroller but optimizes each so it can be carried out very rapidly (usually within a single clock cycle). These RISC structure gives the following advantages. The RISC structure less and

simple instructions as compared to CISC.

The execution time is same for most of the instructions (except for load and store).

The execution time required is very less (5 million instructions/second (approximately).

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BUS BUS is used to transfer and receive the data from one peripheral to another. It is

classified into two types such as data bus and address.

Data Bus: It is used for only transfer or receive the data.

Address Bus: Address bus is used to transmit the memory address from the peripherals to the CPU. I/O pins are used to interface the external peripherals; UART and USART both are serial communication protocols which are used for interfacing serial devices like GSM, GPS, Bluetooth, IR, etc.

Serial Communication

The transfer of one bit of data at time consecutively over a communication channel

is called Serial Communication.

There are three protocols of serial communication

USART: It stands for Universal synchronous and Asynchronous Receiver and Transmitter which provides a serial communication in two devices. In this protocol data is transmitted and received bit by bit through a single wire according to the clock pulses. To send and receive data serially the PIC microcontroller has two pins TXD and RXD.

SPI Protocol: SPI stands for Serial Peripheral Interface. It is used to send data between PIC microcontrollers and other peripherals like sensors, shift registers and SD cards. Three wire SPI communications is supported in PIC microcontroller between two devices on a common clock source. SPI protocol has greater data handling capability than that of the USART.

I2C Protocol: I2C stands for Inter Integrated Circuit, and this protocol is used to connect low speed devices like microcontrollers, EEPROMS and A/D converters. PIC microcontroller support two wire Interface or I2C communication between two devices which can work as both Master and Slave device.

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Parallel slave Port (PSP) PIC microcontroller offers a mechanism by which an 8 bit parallel bi- directional data

transfer can be achieved between a PIC microcontroller and a PC. PIC microcontroller’s Port D and Port E are used in this data transfer. For this data transfer Port D of PIC microcontroller is configured as a Parallel slave Port (PSP) by setting bit 4 of TRISE register. The pins of Port E function as control pins (RD, WR, and CS) for data transfer.

Capture, Compare, PWM (CCP) Module A CCP module works in the following three modes:

Capture Mode: In this mode time is captured when a signal is arrived, or we can say that, when the CCP pin goes high it captures the value of the Timer1.

Compare Mode: It works same as an Analog comparator, which means that when timer 1’s value reaches some reference value it will give an output signal.

PWM Mode: This mode provides a 10 bit resolution pulse and duty cycle that is programmable.

A/D Converter It converts the Analog voltage levels to

digital voltage values. In PIC Microcontroller, ADC has 8-channels and has resolution of 10-bit, which means that if we have to convert an Analog voltage between 0V to 5V the converter will divide it in to 2^10 levels (1024 levels). The special function registers ADCON0 and ADCON1 control the operation of ADC. The converter stores the lower 8 bits in ADRESL register and the upper bits in the ADRESH register. Reference voltage of 5V is required for the operation of the converter.

The ADC in PIC16F877A with 10 bit resolution is of Successive Approximation Type.

This is multiplexed among 8 input pins. The A/D module has high and low-voltage reference input that is software selectable to some combination of VDD, VSS, RA2 or RA3. With 5V as the Vref the resolution of PIC16F877A ADC can be determined as below:

Resolution of ADC = Vref/(2^10-1) = 5/1023 =0.004887 = 4.887mv

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For the A/D converter to meet its specified accuracy, the charge holding capacitor (CHOLD) of the PIC must be allowed to fully charge to the input channel voltage level. The source impedance (RS) and the internal sampling switch impedance (RSS) directly affect the time required to charge the capacitor CHOLD. The sampling switch (RSS) impedance varies over the device voltage (VDD); The maximum recommended impedance for analog sources is 2.5 kΩ.

After the analog input channel is selected (changed), the acquisition must be done before the conversion can be started. The minimum acquisition time, for 10 bit resolution is:

A/D conversion time = 1.6µs /bit x 10 bits = 19.72µs.

Interrupts PIC16F877a has 8 interrupt sources in it. An interrupt source is some event that

generates interrupt, this source could be a timer like interrupts are generated after every 1 sec, or it could also be pin state change event, like if pin state is changed then interrupt will be generated.

So, PIC16F877a Interrupts can be generated by following 8 ways:

a. External Interrupts. b. Timer Interrupts ( Timer0 / Timer1). c. Port B State Change. d. Parallel Slave Port Read/Write. e. A/D Converter. f. Serial Receive / Transmit. g. PWM (CCP1 / CCP2). h. EEPROM Write Operation.

PIC16F877a Interrupts are associated with below 5 registers:

INTCON PIE1 PIR1 PIE2 PIR2

Reset It resets the microcontroller and is active low, meaning that it

should constantly be given a voltage of 5V and if 0 V are given then the controller is reset. Resetting the controller will bring it back to the first line of the program that has been burned into the IC.

A push button and a resistor is connected to the pin. The pin is already being supplied by constant 5V. When we want to reset the IC we just have to push the button which will bring the MCLR pin to 0 potential thereby resetting the controller.

List of Interrupts • External • Timer 0 • Timer 1 • RB Port Change • Parallel Slave Port Read/Write • A/D Converter • USART Receive • USART Transmit • Synchronous Serial Port • CCP1 (Capture, Compare, PWM) • CCP2 (Capture, Compare, PWM) • TMR2 to PR2 Match • Comparator • EEPROM Write Operation • Bus Collision

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Oscillator PIN 13: OSC1/CLKIN: This is the oscillator input or the external clock input pin. PIN 14: OSC2/CLKOUT: This is the oscillator output pin. A crystal resonator is connected between pin 13 and 14 to provide external clock to the microcontroller. ¼ of the frequency of OSC1 is outputted by OSC2 in case of RC mode. This indicates the instruction cycle rate.

Oscillator unit basically is an oscillation/clock generating circuit which is used for providing proper clock pulses to the PIC chip. This clock pulses also helps the timing and counting applications. A PIC chip normally uses various types of clock generators. According to the application and the type of PIC used, the oscillators and its frequencies may vary. RC (Resistor-Capacitor), LC (Inductor-Capacitor), RLC (Resistor-Inductor-capacitor), crystal oscillators, etc. are the normal oscillators used with A PIC chip. The PIC16f877a has four oscillator modes namely LP, XT, HS, and RC.

The remaining blocks are explained in detailed in the upcoming topics.

2.4 Memory organization

The basic building block of PIC 16F877A is based on Harvard architecture. The Harvard architecture is a computer architecture with separate storage and signal pathways for instructions and data. It contrasts with the von Neumann architecture, where program instructions and data share the same memory and pathways.

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Because the Harvard architecture has separate program memory and data memory, it can provide greater data-memory bandwidth, making it the ideal choice for digital signal processing. Most systems designed for digital signal processing (DSP) adopt the Harvard architecture.

The Harvard architecture offers separate storage and signal buses for instructions and data. This architecture has data storage entirely contained within the CPU, and there is no access to the instruction storage as data. Computers have separate memory areas for program instructions and data using internal data buses, allowing simultaneous access to both instructions and data.

Programs needed to be loaded by an operator; the processor could not boot itself. In a Harvard architecture, there is no need to make the two memories share properties.

The memory of a PIC 16F877 chip is divided into 3 sections as shown in the below figure

a. Program memory b. Data memory c. Data EEPROM

Flash memory – In the IC No.16F877A. (F – stands fro Flash memory). This is a special type of memory where READ, WRITE, and ERASE operations can be

done many times. This type of memory was invented by INTEL corporation in 1980. A PIC Chip normally contains a certain amount of flash memory.

Program Memory The Prgram memory of PIC I6F877A is ROM memory type and this memory contains

the program (which we had written), after we've burned it. As a reminder, Program Counter executes commands stored in the program memory, one after the other.

The PIC16F87XA devices have a 13-bit program counter capable of addressing an 8K word x 14 bit program memory space. This memory is used to store the program after we burn it to the microcontroller. The PIC16F876A/877A devices have 8K words x 14 bits of Flash program memory that can be electrically erased and reprogrammed. Each time we burn program into the micro, we erase an old program and write a new one.

Program counters (PC) is used to keep the track of the program execution by holding the address of

the current instruction. The counter is automatically incremented to the next instruction during the current instruction execution.

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Reset vector Each time the main program execution starts at address 0000.

Interrupt vector The address 0004 is “reserved” for the “interrupt service routine” (ISR) program.

Whenever it is called (ISR) program will run.

Stack When an interrupt occurs, first the PIC microcontroller has to execute the interrupt

and the existing process address. Then that is being executed is stored in the stack. After completing the execution of the interrupt, the microcontroller calls the process with the help of address, which is stored in the stack and get executes the process.

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Data EEPROM (Electrically Erasable Programmable Read-Only Memory) A memory that allows storing the variables as a result of burning the written

program. Each one of them has a different role. Program Memory and Data Memory two memories that are needed to build a program, and Data EEPROM is used to save data after the microcontroller is turn off.

The data EEPROM and Flash program memory is readable and writable during normal operation (over the full VDD range). This memory is not directly mapped in the register file space.

Instead, it is indirectly addressed through the Special Function Registers. There are six SFRs used to read and write this memory:

The EEPROM data memory allows single-byte read and writes. The Flash program memory allows single-word reads and four-word block writes. Program memory write operations automatically perform an erase-before write on blocks of four words. A byte write in data EEPROM memory automatically erases the location and writes the new data (erase-before-write). The write time is controlled by an on-chip timer. The write/erase voltages are generated by an on-chip charge pump, rated to operate over the voltage range of the device for byte or word operations.

Data Memory The data memory is partitioned into multiple banks which contain the General

Purpose Registers and the Special Function Registers. Bits RP1 (Status<6>) and RP0 (Status<5>) are the bank select bits.

http://www.microcontrollerboard.com/pic_memory_organization.html

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The data memory is partitioned into multiple banks which contain the General Purpose Registers (GPR) and the Special Function Registers (SFR). The lower bytes of the each bank are reserved for the Special Function Registers and above the SFRs are general purpose registers implemented as static RAM. The variables that we store in the Data Memory during the program are deleted after we turn of the microcontroller. The Number of banks in the PIC16F877A is four bank. The bits RP1 and RP0 bits of the status register are used to select these banks. Each bank extends up to 128 Bytes

General Purpose Register File: The general purpose register file is another name for the microcontroller’s RAM. Data can be written to each 8-bit location updated and retrieved any number of times.

Special Purpose Register File: The special function register file consists of input, output ports and control registers used to configure each 8-bit port either as input or output. It contains registers that provide the data input and data output to a chip resources like Timers Semi Ports and Analog to Digital converter and also the registers that contains control bits for selecting the mode of operation and also enabling or disabling its operation.

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Status Register The STATUS register is a 8-bit register that stores the status of the processor. This

also stores carry, zero and digit carry bits.

bit 7: IRP: Register Bank Select bit (used for indirect addressing) 0 = Bank 0, 1 (00h - FFh) 1 = Bank 2, 3 (100h - 1FFh) The IRP bit is not used by the PIC16F8X. IRP should be maintained clear. bit 6-5: RP1:RP0: Register Bank Select bits (used for direct addressing) 00 = Bank 0 (00h - 7Fh) 01 = Bank 1 (80h - FFh) 10 = Bank 2 (100h - 17Fh) 11 = Bank 3 (180h - 1FFh) Each bank is 128 bytes. Only bit RP0 is used by the PIC16F8X. RP1 should be maintained clear. bit 4: TO: Time-out bit 1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred

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bit 3: PD: Power-down bit 1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction bit 2: Z: Zero bit 1 = The result of an arithmetic or logic operation is zero 0 = The result of an arithmetic or logic operation is not zero bit (for ADDWF and ADDLW instructions) (For borrow the polarity is reversed) bit 1: DC: Digit carry/borrow 1 = A carry-out from the 4th low order bit of the result occurred 0 = No carry-out from the 4th low order bit of the result bit (for ADDWF and ADDLW instructions) bit 0: C: Carry/borrow 1 = A carry-out from the most significant bit of the result occurred 0 = No carry-out from the most significant bit of the result occurred Note: For borrow the second operand the polarity is reversed. A subtraction is executed by adding the two’s complement of. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order bit of the source register.

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2.5 Pin Diagram

The PIC 16F877A is a Dual inline package (DIP) IC there are 40 pins of this microcontroller IC. It consists of two 8 bit and one 16 bit timer. Capture and compare modules, serial ports, parallel ports and five input/output ports are also present in it. 33 pins for input and output. This picture shows the pinout diagram of PIC16F877A.

Following table shows the pin description of each pin. Some pins are capable to

perform more than one function.

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2.6 Input/Output Ports

PIC 16F877 series normally has five input/output ports. They are used for the input/output interfacing with other devices/circuits. Most of these port pins are multiplexed for handling alternate function for peripheral features on the devices. All ports in a PIC chip are bi-directional. When the peripheral action is enabled in a pin, it may not be used as its general input/output functions. The PIC 16F877 chip basically has 5 input/output ports.

PIC16F877A PORTS The five input/output ports and its functions are given below.

PORT A AND THE TRIS A REGISTERS

PORT A is a 6-bit wide bi-directional port, the direction of this port is controlled by TRIS A data direction register. Setting a TRIS A (=1) makes corresponding PORT A pin as an input, clearing the TRIS A (=0) making the corresponding PORT A pin as an output Pin RA4 is multiplexed with the “Timer0” module clock input to become the RA4/T0CKI pin and functioning either input/output operation or Timer0 clock functioning module. The RA4/T0CKI pin is a Schmitt Trigger input and an open-drain output. All other PORT A pins have TTL input levels and full CMOS output drivers.

Other PORT A pins in this microcontroller multiplexed with analog inputs and the analog VREF input for both the A/D converters and the comparators. The operation of each pin is selected by clearing/setting the appropriate control bits in the ADCON1 and/or CMCON registers. The TRIS A register controls the direction of the PORT pins even when they are being used as analog inputs. The user must ensure the bits in the TRISA register are maintained set when using them as analog inputs.

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PORT B AND THE TRIS B REGISTERS PORT B is also an 8 bit bi-directional PORT.

Its direction controlled and maintained by TRIS B data direction register. Setting the TRIS B into logic ‘1’ makes the corresponding “PORT B” pin as an input. Clearing the TRIS B bit make PORT B as an output. Three pins of PORT B are multiplexed with the In-Circuit Debugger and Low-Voltage Programming function: RB3/PGM, RB6/PGC and RB7/PGD for performing its alternate functions.

PORT C AND THE TRIS C REGISTERS PORT C is an 8-bit wide, bidirectional PORT which controlled and maintained by TRIS

C data direction register. Setting a TRIS C bit (= 1) will make the corresponding PORT C pin an input (i.e., put the corresponding output driver in a High-Impedance mode). Clearing a TRIS C bit (= 0) will make the corresponding PORT C pin an output PORT C is also multiplexed with several peripheral functions. PORT C pins have Schmitt Trigger input buffers.

When enabling peripheral functions, more care should be taken in defining TRIS bits for each PORT C pin as compared to other. Some peripherals override the TRIS bit to make a pin an output, while other peripherals override the TRIS bit to make a pin an input. Since the TRIS bit override is in effect while the peripheral is enabled, read-modify write instructions (BSF, BCF, and XORWF) with TRISC as the destination, should be avoided. The user should refer to the corresponding peripheral section for the correct TRIS bit settings.

PORT D AND TRIS D REGISTERS PORT D is an 8-bit PORT with

bi-directional nature. This port also with Schmitt Trigger input buffers, each pin in this PORT D individually configurable as either input or output. PORT D can be configured as an 8-bit wide microprocessor PORT (functioning as Parallel Slave PORT) by setting control bit, PSPMODE ((TRISE<4>). In this mode, the input buffers are TTL.

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PORT E AND TRIS E REGISTERS PORT E has only three pins (RE0/RD/AN5, RE1/WR/AN6 and RE2/CS/AN7) which are

individually configurable as inputs or outputs. These pins controllable by using its corresponding data direction register “TRIS E”. These pins also have Schmitt Trigger input buffers. The PORT E pins become the I/O control inputs for the microprocessor PORT when bit PSPMODE is set. In this mode, the user must make certain that the TRIS E bits are set and that the pins are configured as digital inputs. Also, ensure that ADCON1 is configured for digital I/O. In this mode, the input buffers are TTL.

TRISE register which also controls the Parallel Slave PORT operation. PORT E pins are multiplexed with analog inputs. When selected for analog input, these pins will read as ‘0’s. TRIS E controls the direction of the RE pins, even when they are being used as analog inputs. The user must make sure to keep the pins configured as inputs when using them as analog inputs.

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2.7. Timers

As the name suggests these are used to measure the time or generate the accurate time delay. The microcontroller can also generate/measure the required time delays by running loops, but the timer relieves the CPU from that redundant and repetitive task, allowing it to allocate maximum processing time for other tasks.

The timer is nothing but a simple binary counter that can be configured to count clock pulses (Internal/External). Once it reaches the max value, it will roll back to zero setting up an OverFlow flag and generates the interrupt if enabled. PIC16F877a has three timers.

• Timer0 (8-bit timer).



All Timers can act as a timer or counter or PWM Generation.

To start using a timer we should understand some of the fancy terms like 8-bit/16-

bit timer, Prescaler, Timer interrupts and Fosc. Now, let us see what each one really

means. As said earlier there are both the 8-bit and 16-bit Timers in our PIC16F877A. The

main difference between them is that the 16-bit Timer has a much better Resolution than

the 8-bit Timer.

Prescaler is a name for the part of a microcontroller that divides oscillator clock

before it will reach logic that increases timer status. The range of the Prescaler id is from 1

to 256 and the value of the Prescaler can be set using the OPTION Register (we will see this

register later).

As the timer increments and when it reaches its maximum value of 255 (for 8-bit

timers) or 65536 (for 16-bit timers), it will trigger an interrupt and initialize itself to 0 back

again. This interrupt is called as the Timer Interrupt. This interrupt informs the MCU that

this particular time has lapped.

The Fosc stands for Frequency of the Oscillator, it is the frequency of the Crystal

used. The time taken for the Timer register depends on the value of Prescaler and the

value of the Fosc.

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Timer0 The Timer0 module timer/counter has the following features:

8-bit timer/counter

Readable and writable

8-bit software programmable prescaler

Internal (4 Mhz) or external clock select

Interrupt on overflow from FFh to 00h

Edge select (rising or falling) for external clock

Timer0 has a register called TMR0 Register, which is 8 bits of size. We can write the desired value into the register which will increment as the program progresses. Frequency varies depending on the Prescaler. Maximum value that can be assigned to this register is 255.

Prescaler - Frequency divider. We can use Prescaler for further division of the system clock. The options are:

The structure of the OPTION_REG register We perform all the necessary settings with OPTION_REG Register. The size of the

register is 8 bits.

Initializing the OPTION_REG register

The following is an example how we can initialize the OPTION_REG:

1. PSA=0; // Prescaler is assigned to the Timer0 module 2. PS0=1; // Prescaler rate bits 3. PS1=1; // are set to “111” 4. PS2=1; // which means divide by 256 5. TOSE=0; // rising edge 6. TOCS=0; // Internal instruction cycle clock

http://www.microcontrollerboard.com/sbi/support-files/option-register.html

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Timer1 The Timer1 module, timer/counter, has the following features:

• 16-bit timer/counter consisting of two 8-bit registers (TMR1H and TMR1L)

• readable and writable

• 8-bit software programmable pre scaler

• Internal (4 Mhz) or external clock select

• Interrupt on overflow from FFFFh to 0000h

Timer1 has a register called TMR1 register, which is 16 bits of size. Actually, the TMR1 consists of two 8-bits registers: TMR1H

TMR1L

It increments from 0000h to the maximum value of 0xFFFFh (or 0 b1111 1111 1111

1111 or 65,535 decimal). The TMR1 interrupt, if enabled, is generated on overflow which

is latched in interrupt flag bit, TMR1IF (PIR1<0>). This interrupt can be enabled/disabled by

setting/clearing TMR1 interrupt enable bit, TMR1IE (PIE1<0>).

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TMR1IF – TMR1 overflow Interrupt Flag bit.

This flag marks the end of ONE cycle count. The flag need to be reset in the software

if you want to do another cycle count. We can read the value of the register TMR1 and

write into. We can reset its value at any given moment (write) or we can check if there is a

certain numeric value that we need (read).

Prescaler – Frequency divider.

We can use Prescaler for further division of the system clock. The size of the register is

2-bit only, so you can make four different division. The options are:

• 1:1

• 1:2

• 1:4

• 1:8

Timer2

The Timer2 module, timer/counter, has the following features: • Two 8-bit registers (TMR2 and PR2)

• readable and writable

• a prescaler and a postscaler

• connected only to an internal clock - 4 MHz crystal

• Interrupt on overflow

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Timer2 has 2 count registers:

TMR2 and PR2. The size of each registers is 8-bit in which we can write numbers from 0 to 255. The TMR2 register is readable and writable and is cleared on any device Reset. PR2 is a readable and writable register and initialized to FFh upon Reset. Register TMR2 is used to store the "initial" count value (the value from which it begins to count). Register PR2 is used to store the "ending" count value (the maximum value we need/want to reach). ie: using Timer2 we can determine the started count value, the final count value, and the count will be between these two values. The Timer2 increments from 00h until it matches PR2 and then resets to 00h on the next increment cycle.

Prescaler and Postscaler :

Timer2 is an 8-bit timer with a prescaler and a postscaler. Each allows to make additional division of the frequency clock source. Prescaler divides the frequency clock source BEFORE the counting take place at the register TMR2, thus the counting inside the TMR2 register is performed based on the divided frequency clock source by the Prescaler

The match output of TMR2 goes through a 4-bit postscaler (which gives a 1:1 to 1:16 scaling inclusive) to generate a TMR2 interrupt (latched in flag bit, TMR2IF (PIR1<1>)). Postscaler divides the frequency that comes out of the Comparator again for the last time. TIMER2 Prescaler and Postscaler

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2.8 Programming of PIC. Compiler for PIC16F877A microcontroller

Three popular compiler which are used to program pic microcontrollers are MPLAB XC8, Mikro C for pic, PIC CCS compiler and Hi-Tech compiler.

The official compiler is MPLAB XC8 compiler which is developed by manufactures of PIC16F877A.

We generally recommend Mikro C for pic compiler for beginners and MPLAB XC8 compiler for those who want to learn pic microcontrollers programming from register level bare metal concepts.

• Variables • Looping • Decisions.

Variables

The purpose of an embedded program is to read in data or control inputs, process them, and operate the outputs as required.

Input from parallel, serial, and analog ports are held in the file registers for temporary storage and processing; and the results are output later on, as data or a signal. The program for processing the data usually contains repetitive loops and conditional branching, which depends on an input or calculated value.

Variables most programs need to process data in some way, and named variables are needed to hold their values. A variable name is a label attached to the memory location where the variable value is stored.

When working in assembly language, a register label acts as the variable name and has to be assigned explicitly. In C, the variable label is automatically assigned to the next available location or locations (many variable types need more than 1 byte of memory). The variable name and type must be declared at the start of the program block, so that the compiler can allocate a corresponding set of locations. Variable values are assumed to be in decimal by default; so if a value is given in hexadecimal in the source code, it must be written with the prefix 0x, so that 0xFF represents 255, for example.

/****** Source code file: VARI.C *******/

#include "16F877A.h"

void main()

int x; // Declare variable and type

x=99; // Assign variable value

output_D(x); // Display the value in binary

A variable called x is used in the program in Listing 2.2, VARI.C. Longer labels are

sometimes preferable, such as “output value,” but spaces are not allowed. Only alphanumeric characters (a–z, A–Z, 0–9) and underscore, instead of space, can be used. By

https://www.microchip.com/mplab/compilers

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default, the CCS compiler is not case sensitive, so ‘a’ is the same as ‘A’ (even though the ASCII code is different). A limited number of key words in C, such as main and include, must not be used as variable names.

The variable x is an 8-bit integer with whole number values 0–25510. The value in binary can be seen when it is output at an 8-bit port. Generally, C integers (int) are stored as 16- bit values, but C for 8-bit microcontrollers uses a default 8-bit integer format. In Program VARI.C, an initial value is assigned to the variable (99), which is then used in the output function. The point here is that the variable value can now be modified without having to change the output function call itself. In the program, an 8-bit variable x is declared and assigned a value 99 using the “equals” operator. It is then output to Port D using the standard output function.

Variable Types

Variables are needed to store the data values used in the program. Variable labels

are attached to specific locations when they are declared at the beginning of the program,

so the MCU can locate the data required by each operation in the file registers.

a. Integers

We have seen the integer (whole number) variable in use. In the 8-bit MCU, the default type is an unsigned 8-bit number, giving a range of values of 0–255. This obviously is inadequate for many purposes, so 16- and 32-bit integer types are also needed. The range of a number is determined by the number of different binary codes that can be represented. If n is the number of bits, 2n different codes are possible. As 0 must be included, the highest number is 2(n—1). Hence, the 16-bit unsigned integer has the range 0–65535 (216 — 1) and the 32 bit 0–4294967295 (232 — 1). There is also a 1-bit type for bit storage.

b. Signed Integers The signed integer uses the most significant bit (MSB) as the sign bit, so the range is

accordingly reduced by half. MSB = 0 represents a positive number, MSB = 1 indicates a negative number. Therefore, the range for a 16-bit signed integer is –32767 to +32767. The sign bit must be processed separately to get the right answer from a calculation.

Range of Integer Variables

Name Type Minimum Maximum Range

int1 1 bit 0 1 1 = 20

unsigned int8 8 bits 0 255 256 = 28

signed int8 8 bits —127 +127 256 = 28


signed int16 16 bits —32767 +32767 65536 = 216


signed int32 32 bits —2147483647 +2147483647 4294967296 = 232

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c. Floating Point

Integers can represent only a limited range of numbers, with a precision of ±0.5.

Therefore, the floating point (FP) type should be used for many calculations, particularly

those with a fractional result. The 32-bit FP format can represent decimal numbers from

about 10—39 to 10+38, with a precision of about 10—7 (±0.0000001). The number is stored in

exponential format, as used in a standard calculator. Twenty-three bits are used for the

significant digits, called the mantissa. Eight bits are used for the exponent part and one for

the sign. The IEEE standard form has the sign bit as the MSB, but Microchip and CCS use a

slightly more logical form, where the sign bit is the MSB of the third byte, leaving the

exponent to be represented by the complete high byte.

d. Character Variable

Text characters are generally represented by ASCII codes. The basic set of 7- bit

characters includes the upper and lower case letters and the numerals and punctuation

marks found on the standard computer keyboard. For example, capital (upper case) A is

1000001 (6510). The numeric characters run from 0x30 (0) to 0x39 (9), so to convert to the

actual number from ASCII, simply subtract 0x30. The character variable is indicated in C

source code in single quotes. For example the statement answer ='Y'; will assign the value

0x59 to the variable ‘answer’.

Looping

Most real-time applications need to execute continuously until the processor is

turned off or reset. Therefore, the program generally jumps back at the end to repeat the

main control loop.

The condition for continuing to repeat the block between the while braces is

contained in the parentheses following the while keyword. The block is executed if the

value, or result of the expression, in the parentheses is not zero. In this case, it is 1, which

means the condition is always true; and the loop repeats endlessly.

This program represents in simple form the general structure of embedded

applications, where an initialization phase is followed by an endless control loop. Within

the loop, the value of x is incremented (x++). The output therefore appears to count up in

binary when executing. When it reaches the maximum for an 8-bit count (11111111 =

255), it rolls over to 0 and starts again.

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Endless Loop #include "16F877A.h"

void main()

int x; // Declare variable

while(1) // Loop endlessly

output D(x); // Display value

x++; // Increment value

IF Statement // IFIN.C Tests an input


void main()

int x; // Declare variable

output_D(0); // Clear all outputs

while(1) // Loop always

x=input(PIN_C0); // Get input state

if(x==1)output_high(PIN_D0); // Change output

Decision Making

The simplest way to illustrate basic decision making is to change an output depending on the state of an input. The switch generates an input at RC0 and RD0 provides the test output.

The common keyword for selection in many high level languages is IF. Program IFIN.C has the usual endless “while” loop but contains a statement to switch off Port D initially. The input state is read within the loop using the bit read function input (PIN_C0). This assigns the input value 1 or 0 to the variable x. The value is then tested in the if statement and the output set accordingly. Note that the test uses a double equals to differentiate it from the assignment operator used in the previous statement. The effect of the program is to switch on the output if the input is high. The switch needs to be closed before running to see this effect. The LED cannot be switched off again until the program is restarted.

Loop Control The program can be simplified by combining the input function with the condition

statement as follows:

`


Conditional Loop #include "16F877A.h"

#use delay (clock=1000000) //MUC clock = 1 MHz

void main()

while(1)

while(input(PIN_C0)) // Repeat while switch is open

output_high(PIN_D0); //switch on LED

delay_ms(300); //Delay 0.3s

output_low(PIN_D0); //Switch off LED

delay_ms(500); //Delay 0.5s

output_low(PIN_D0); //Switch off LED

The conditional sequence can also be selected by a while condition. In above

program, the input is tested in the loop condition statement and the output flashed on

and off while the switch is open (input high). If the switch is closed, the flash loop is not

executed and the LED is switched off.

The program also demonstrates the delay function. If this were absent, the loop

would execute in just a few microseconds, since each machine code instruction takes 4 μs

at a clock rate of 1 MHz. The flashing of the output would be invisible. The delay required

(in milliseconds) is given as the function parameter, and a reference to the function library

is provided at the start of the program with the #use directive. This allows the compiler to

find the library routine delay_ms(). The clock speed of the target processor must be given

in the use directive, so that the correct delay is calculated within the function.

Compare the syntax of the I/O statements. The function output high (PIN_nn) is an

output operation to set the port pin high. The function input (PIN_nn) is an input function

that returns a 1 or 0 from the input pin, which can be tested by an IF or WHILE statement.

The ports are initialized automatically within these functions.

FOR Loop

The WHILE loop repeats until some external event or internally modified value

satisfies the test condition. In other cases, we need a loop to repeat a fixed number of

times. The FOR loop uses a loop control variable, which is set to an initial value and

`


FOR Loop // FORLOOP.C Repeat loop a set number of times #include "16F877A.h" #use delay (clock=1000000) void main()

int x; while(input(PIN_C0)); //Wait until switch is closed for (x=0; x<5; x++) //FOR loop condition

output_high(PIN_D0); //Flash sequence delay_ms(500); output_low(PIN_D0); delay_ms(500);

while(!input(PIN_C0)); //Wait for Reset

modified for each iteration while a defined condition is true. In the demo program

FORLOOP.C, the loop control parameters are given within the parentheses that follow the

for keyword. The loop control variable x is initially set to 0, and the loop continues while it

is less than 6. Value x is incremented each time round the loop. The effect is to flash the

output five times.

The FORLOOP program also includes the use of the while loop to wait for the switch

to close before the flash sequence begins. In addition, an unconditional while loop

terminates the program, preventing the program execution from running into undefined

locations after the end of the sequence. This is advisable whenever the program does not

run in a continuous loop. Note that the use of the empty braces, which contain no code, is

optional.

Siren Program A program combining some of these basic features is shown in SIREN.C. This

program outputs to a sounder rather than an LED, operating at a higher frequency. The delay is therefore in microseconds. The output is generated when the switch is closed (input C0 low). The delay picks up the incrementing value of “step,” giving a longer pulse each time the for loop is executed. This causes a burst of 255 pulses of increasing length (reducing frequency), repeating while the input is on. Note that 255 is the maximum value allowed for “step,” as it is an 8-bit variable. When run in VSM, the output can be heard via the simulation host PC sound card. Note the inversion of the input test condition using ! = not true.

`


SIREN Program


#use delay (clock=1000000)

void main()

int step;

while(1)

while(!input(PIN_C0))

for(step=0;step<255;step++)

output_high(PIN_D0);

delay_us(step);

output_low(PIN_D0);

delay_us(step);

The header information is now more extensive, as would be the case in a real application. Generally, the more complex a program, the more information is needed in the header. Information about the author and program version and/or date, the compiler version, and the intended target system are all useful. The program description is important, as this summarizes the specification for the program.

PIC16 C Data Operations

A main function of any computer program is to carry out calculations and other forms of data processing. Data structures are made up of different types of numerical and character variables, and a range of arithmetical and logical operations are needed. Microcontroller programs do not generally need to process large volumes of data, but processing speed is often important.

Arithmetic and Logical Operations

Operation Operator Description Source Code Example Result

Single operand

Increment ++ Add 1 to integer

result = num1++; 0000 0000 0000 0001

Decrement -- Subtract 1 from integer

result = num1--; 1111 1111 1111 1110

Complement ~ Invert all bits of integer

result = num1; 0101 0010 1010 1101

`


Arithmetic operation

Add + Integer or result = num1+num2; 0000 1010 0001

float +0000 0111 0001

Subtract — Integer or result = num1-num2; 0000 1010 0000

float –0000 0011 0111

Multiply * Integer or result = num1*num2; 0000 1010 0001

float *0000 0011 1110

Divide / Integer or result = num1 /num2; 0000 1100 0000

float /0000 0011 0100

Logical operation

Logical AND & Integer result = num1&num2; 1001 0011 0001

bitwise &0111 0001 0001

Logical OR | Integer result = num1|num2; 1001 0011 1111

bitwise |0111 0001 0011

Exclusive OR ^ Integer result = num1^num2; 1001 0011 1110

bitwise ^0111 0001 0010

Conditional Operators Operation Symbol Example

Equal to == if(a == 0) b = b+5;

Not equal to != if(a != 1) b = b+4;

Greater than > if(a > 2) b = b+3;

Less than < if(a < 3) b = b+2;

Greater than or equal to >= if(a >= 4) b = b+1;

Less than or equal to <= if(a <= 5) b = b+0;

Program structure The structure of a C program is created using functions. This is a block of code

written and executed as a self-contained process, receiving the required parameters (data to be processed) from the calling function and returning results to it. Main () is the primary function in all C programs, within which the rest of the program is constructed.

When running on a PC, main() is called by the operating system, and control is returned to the OS when the C program is terminated. In the microcontroller, main() is simply used to indicate the start of the main control sequence, and more care needs to be taken in terminating the program. Normally, the program runs in a continuous loop, but if not, the final statement should be while(1);, which causes the program to wait and prevents the program running into undefined locations following the application code.

`


3.0 NODE MCU - ESP8266

3.1 Introduction to Node MCU and Its Features.

Node MCU (Microcontroller Unit)

Today, IOT (Internet of Things) applications are on

the rise, and connecting objects are getting more and

more important. There are several ways to connect

objects using Wi-Fi protocol.

NodeMCU is an open-source platform based on

ESP8266 which can connect objects and let data transfer

using the Wi-Fi protocol. In addition, by providing some of the most important features of

microcontrollers such as GPIO, PWM, ADC etc, we can design more user friendly, remote

controlled or self actuating products.

The ESP8266 is a microcontroller with Wi-Fi capability. There are different modules and development boards with this system. Some development boards use basic ESP8266 modules and some integrate the chip flash memory and the antenna on the PCB.

NODEMCU is a development board with ESP8266 and a firmware with the same name.

NodeMCU ESP8266 Specifications & Features

Microcontroller: Tensilica 32-bit RISC CPU Xtensa LX106

Operating Voltage: 3.3V

Input Voltage: 7-12V

Digital I/O Pins (DIO): 16

Analog Input Pins (ADC): 1

UARTs: 1

SPIs: 1

I2Cs: 1

Flash Memory: 4 MB

SRAM: 64 KB

Clock Speed: 80 MHz

USB-TTL based on CP2102 is included onboard, Enabling Plug n Play

PCB Antenna

Small Sized module to fit smartly inside your IoT projects

`


Attributes ESP8266 NODEMCU V2 NODEMCU V3

Microcontroller ESP8266 ESP8266

Operating Voltage 3.3V 3.3V

Power supply 7V – 12V 7V – 12V

Current consumption 15 µA – 400 mA 15 µA – 400 mA

Current consumption Deep Sleep 0.5 µA 0.5 µA

Digital I/O Pins 11 or 13 16

Digital I/O Pins with PWM 11 or 13 16

Analog Input Pins 1 1

SPI/I2C/I2S/UART 2/1/2/2 2/1/2/2

DC Current per I/O Pin 12 mA 12 mA

DC Current for 3.3V Pin

Flash Memory 4 MB 4 MB

SRAM n.A 64 KB

EEPROM 512 bytes 512 bytes

Clock Speed 52 MHz 80 MHz

Length 48 mm 58 mm

Width 26 mm 31 mm

WIFI yes yes

Bluetooth no no

Touch sensor no no

CAN no no

Ethernet MAC Interface no no

Temperature Sensor no no

Hall effect sensor no no

Power jack no no

USB connection yes yes

`


The NodeMCU ESP8266 development board comes with the ESP-12E module containing

the ESP8266 micrcontroller having Tensilica Xtensa 32-bit LX106 RISC microprocessor. This

microprocessor supports

RTOS and operates at

80MHz to 160 MHz

adjustable clock

frequency. NodeMCU has

128 KB RAM and 4MB of

Flash memory to store

data and programs. Its

high processing power

with in-built Wi-Fi /

Bluetooth and Deep Sleep Operating features make it ideal for IoT projects.

NodeMCU can be powered using a Micro USB jack and VIN pin (External Supply Pin). It

supports UART, SPI, and I2C interface.

3.2 Pin configuration of NODE MCU.

`


NodeMCU Development Board Pinout Configuration

Pin Category Name Description

Power Micro-USB, 3.3V,

GND, Vin

Micro-USB: NodeMCU can be powered through the

USB port

3.3V: Regulated 3.3V can be supplied to this pin to

power the board

GND: Ground pins

Vin: External Power Supply

Control Pins EN, RST The pin and the button reset the microcontroller

Analog Pin A0 Used to measure analog voltage in the range of 0-3.3V

GPIO Pins GPIO1 to

GPIO16

Node MCU has 16 general purpose input-output pins

on its board

SPI Pins SD1, CMD, SD0,

CLK

NodeMCU has four pins available for SPI

communication.

UART Pins TXD0, RXD0,

TXD2, RXD2

NodeMCU has two UART interfaces, UART0 (RXD0 &

TXD0) and UART1 (RXD1 & TXD1). UART1 is used to

upload the firmware/program.

I2C Pins SCL, SDA

NodeMCU has I2C functionality support but due to the

internal functionality of these pins, you have to find

which pin is I2C.

GPIO (General Purpose Input Output) Pins: NodeMCU has general purpose input output pins on its board as shown in above pinout diagram. We can make it digital high/low and control things like LED or switch on it. Also, we can generate PWM signal on these GPIO pins. ADC (Analog to Digital Converter) channel (A0): NodeMCU has one ADC channel/pin on its board.

`


SPI (Serial Peripheral Interface) Pins: NodeMCU based ESP8266 has Hardware SPI (HSPI) with four pins available for SPI communication. It also has SPI pins for Quad-SPI communication. With this SPI interface, we can connect any SPI enabled device with NodeMCU and make communication possible with it. I2C (Inter-Integrated Circuit) Pins: NodeMCU has I2C functionality support on ESP8266 GPIO pins. Due to internal functionality on ESP-12E we cannot use all its GPIOs for I2C functionality. So, do tests before using any GPIO for I2C applications. UART (Universal Asynchronous Receiver Transmitter) Pins: NodeMCU based ESP8266 has two UART interfaces, UART0 and UART1. Since UART0 (RXD0 & TXD0) is used to upload firmware/codes to board, we can’t use them in. Specification Details: https://ecksteinimg.de/Datasheet/CP06031/Datasheet.pdf

https://ecksteinimg.de/Datasheet/CP06031/Datasheet.pdf

`


4.0 NODE MCU AND ARDUINO PROGRAMMING

4.1 Introduction to Arduino and Its Features

A decade ago, working around electronics involved

knowledge in physics and math, expensive lab

equipment, a laboratory type setup and important of all,

love for electronics. But the picture has changed over the

decade or so where the above-mentioned factors

became irrelevant to work around electronics except for

the last part: love for electronics.

There are many reasons which made this possible like

rapid growth in the field of information technology,

lower cost of electronic components and equipment and

widespread availability of the internet.

One such product which made use of the above specified and many other reasons and

made electronics be able reach anyone regardless of their background is “Arduino”. Since

its introduction in 2005, the term “Arduino” has become very popular in the field of

electronics.

Introduction Arduino is an open-source prototyping platform in electronics based on easy-to-use

hardware and software. Subtly speaking,

Arduino is a microcontroller based

prototyping board which can be used in

developing digital devices that can read

inputs like finger on a button, touch on a

screen, light on a sensor etc. and turning it

in to output like switching on an LED,

rotating a motor, playing songs through a

speaker etc.

The Arduino board can be programmed to do anything by simply programming the

microcontroller on board using a set of instructions for which, the Arduino board consists

of a USB plug to communicate with your computer and a bunch of connection sockets that

can be wired to external devices like motors, LEDs etc.

The aim of Arduino is to introduce the world of electronics to people who have less to no

experience in electronics like hobbyists, designers, artists etc.

`


Arduino is based on open-source electronics project i.e., all the design specifications,

schematics, software are available openly to all the

users. Hence, you can buy Arduino boards from vendors

as they are commercially available or else you can make

your own board by if you wish i.e., you can download the

schematic from Arduino’s official website, buy all the

components as per the design specification, assemble all

the components, and make your own board.

Key Features

Arduino boards are able to read analog or digital input signals from different sensors

and turn it into an output such as activating a motor, turning LED on/off, connect to

the cloud and many other actions.

You can control your board functions by sending a set of instructions to the

microcontroller on the board via Arduino IDE (referred to as uploading software).

Unlike most programmable circuit boards, Arduino does not need an extra piece of

hardware (called a programmer) in order to load a new code onto the board. You can

simply use a USB cable.

Additionally, the Arduino IDE uses a simplified version of C++, making it easier to learn

to program.

Finally, Arduino provides a standard form factor that breaks the functions of the

micro-controller into a more accessible package.

Some of the features of the Arduino UNO are as given below: • Microcontroller: ATmega328 • Operating Voltage: 5V • Input Voltage (recommended): 7-12V • Input Voltage (limits): 6-20V • Digital I/O Pins: 14 (of which 6 provide PWM output) • Analog Input Pins: 6 • DC Current per I/O Pin: 40 mA • DC Current for 3.3V Pin: 50 mA • Flash Memory: 32 KB of which 0.5 KB used by bootloader • SRAM: 2 KB (ATmega328) • EEPROM: 1 KB (ATmega328) • Clock Speed: 16 MHz

`


Hardware and Software Arduino boards are generally based on

microcontrollers from Atmel Corporation like 8,

16 or 32-bit AVR architecture based

microcontrollers.

The important feature of the Arduino

boards is the standard connectors. Using these

connectors, we can connect the Arduino board

to other devices like LEDs or add-on modules

called Shields.

The Arduino boards also consists of on-board voltage regulator and crystal

oscillator. They also consist of USB to serial adapter using which the Arduino board can be

programmed using USB connection.

In order to program the Arduino board, we need to use IDE provided by Arduino.

The Arduino IDE is based on Processing programming language and supports C and C++.

Types of Arduino Boards There are many types of Arduino

boards available in the market but all the boards have one thing in common: they can be programmed using the Arduino IDE. The reasons for different types of boards are different power supply requirements, connectivity options, their applications etc.

`


Arduino boards are available in different sizes, form factors, different no. of I/O pins etc.

Some of the commonly known and frequently used Arduino boards are Arduino UNO,

Arduino Mega, Arduino Nano, Arduino Micro and Arduino Lilypad.

Form factor is a hardware design aspect that defines and prescribes the size, shape, and other physical specifications of components, particularly in electronics. A form factor may represent a broad class of similarly sized components, or it may prescribe a specific standard. It may also define an entire system, as in a computer form factor.

Arduino boards based on ATMEGA328 microcontroller

Board Name Operating Volt

Clock Speed

Digital i/o

Analog Inputs

PWM UART Programming Interface

Arduino Uno R3 5V 16MHz 14 6 6 1 USB via ATMega16U2

Arduino Uno R3 SMD

5V 16MHz 14 6 6 1 USB via ATMega16U2

Red Board 5V 16MHz 14 6 6 1 USB via FTDI

Arduino Pro 3.3v/8 MHz

3.3V 8MHz 14 6 6 1 FTDI-Compatible Header

Arduino Pro 5V/16MHz

5V 16MHz 14 6 6 1 FTDI-Compatible Header

Arduino mini 05 5V 16MHz 14 8 6 1 FTDI-Compatible Header

Arduino Pro mini 3.3v/8mhz


Arduino Pro mini 5v/16mhz

5V 16MHz 14 8 6 1 FTDI-Compatible Header

Arduino Ethernet 5V 16MHz 14 6 6 1 FTDI-Compatible Header

Arduino Fio 3.3V 8MHz 14 8 6 1 FTDI-Compatible Header

LilyPad Arduino 328 main board


LilyPad Arduino simple board


Arduino boards based on ATMEGA32u4 microcontroller


Clock Speed

Digital i/o

Analog Inputs


Arduino Leonardo 5V 16MHz 20 12 7 1 Native USB

Pro micro 5V/16MHz 5V 16MHz 14 6 6 1 Native USB

Pro micro 3.3V/8MHz 5V 16MHz 14 6 6 1 Native USB

`


LilyPad Arduino USB 3.3V 8MHz 14 6 6 1 Native USB

Arduino boards based on ATMEGA2560 microcontroller


Clock Speed

Digital i/o

Analog Inputs


Arduino Mega 2560

R3 5V 16MHz 54 16 14 4

USB via ATMega16U2B

Mega Pro 3.3V


Mega Pro 5V 5V 16MHz 54 16 14 4 FTDI-Compatible Header

Mega Pro Mini 3.3V


Arduino boards based on AT91SAM3X8E microcontroller


Clock Speed

Digital i/o

Analog Inputs


Arduino Mega 2560 R3 3.3V 84MHz 54 12 12 4

USB native

There are add-on modules called Arduino Shields which can be used to extend the functionalities of the Arduino boards. Some of the commonly used shields are Arduino Proto shield, Arduino Wi-Fi Shield and Arduino Yun Shield.

4.2 Variables, Data Types & Constants

Variables

What is Variable Scope? Variables in C programming language,

which Arduino uses, have a property

called scope. A scope is a section of the

program and there are three places

where variables can be declared. They are

−

Inside a function or a block, which is called local variables.

In the definition of function parameters, which is called formal parameters.

Outside of all functions, which is called global variables.

`


void setup () int age; age = 0; void loop ()

int x, y; //local variable declaration x = 0; y = 0; //actual initialization

int age, marks; ; //Global variable declaration

float avg= 0; //Global variable declaration

void loop ()

int z; //Local variable declaration

z = 10;

Local Variables Variables that are declared inside a function or block are local variables. They can

be used only by the statements that are inside that function or block of code. Local variables are not known to function outside their own.

Global Variables

Global variables are defined outside of all the functions, usually at the top of the program. The global variables will hold their value throughout the life-time of your program.

A global variable can be accessed by any function. That is, a global variable is

available for use throughout your entire program after its declaration.

Data types

Data types in C refers to an extensive system used

for declaring variables or functions of different types. The

type of a variable determines how much space it occupies

in the storage and how the bit pattern stored is

interpreted.

The following table provides all the data types that

you will use during Arduino programming.

`


void loop ( )

// rest of the code

boolean val = false; // declaration of variable with type boolean and initialize it with false

boolean state = true; // declaration of variable with type boolean and initialize it with true

char chr_a = ‘a’; //declaration of variable with type char and initialize it with character a

char chr_c = 97; //declaration of variable with type char and initialize it with character 97

unsigned char chr_y = 121; // declaration of variable with type Unsigned char and initialize it with character y. ASCII value of ‘y’ = 121

void

The void keyword is used only in function declarations. It indicates that the function

does not return any information to the function from which it was called.

Boolean

A Boolean holds one of two values, true or false. Each Boolean variable occupies

one byte of memory.

Char

A data type that takes up one byte of memory that stores a character value. Character literals are written in single quotes like this: 'A' and for multiple characters, strings use double quotes: "ABC".

However, characters are stored as numbers. You can see the specific encoding in the ASCII chart. This means that it is possible to do arithmetic operations on characters, in which the ASCII value of the character is used. For example, 'A' + 1 has the value 66, since the ASCII value of the capital letter A is 65.

unsigned char

Unsigned char is an unsigned data type that occupies one byte of memory. The unsigned char data type encodes numbers from 0 to 255.

`


byte m = 25; //declaration of variable with type byte and initialize it with 25

int counter = 32; // declaration of variable with type int and initialize it with 32

unsigned int counter = 60; // declaration of variable with type unsigned int and initialize

with 60

word w = 1000; //declaration of variable with type word and initialize it with 1000

long velocity = 102346; //declaration of variable with type Long and initialize it with

102346

byte

A byte stores an 8-bit unsigned number, from 0 to 255.

int

Integers are the primary data-type for number storage. int stores a 16-bit (2-byte)

value. This yields a range of -32,768 to 32,767 (minimum value of -2^15 and a maximum

value of (2^15) - 1).

The int size varies from board to board. On the Arduino Due, for example, an int

stores a 32-bit (4-byte) value. This yields a range of -2,147,483,648 to 2,147,483,647

(minimum value of -2^31 and a maximum value of (2^31) - 1).

Unsigned int

Unsigned ints (unsigned integers) are the same as int in the way that they store a 2-

bytes value. Instead of storing negative numbers, however, they only store positive values,

yielding a useful range of 0 to 65,535 (2^16) - 1). The Due stores a 4-byte (32-bit) value,

ranging from 0 to 4,294,967,295 (2^32 - 1).

Word

On the Uno and other ATMEGA based boards, a word stores a 16-bit unsigned

number. On the Due and Zero, it stores a 32-bit unsigned number.

Long Long variables are extended size variables for number storage, and store 32 bits (4

bytes), from -2,147,483,648 to 2,147,483,647.

`


unsigned long velocity = 101006; // declaration of variable with type Unsigned Long

and initialize it with 101006

short val = 13; //declaration of variable with type short and initialize it with 13

float num = 1.352; //declaration of variable with type float and initialize it with 1.352

double num = 45.352 ;// declaration of variable with type double and initialize it with

45.352

Unsigned long Unsigned long variables are extended size variables for number storage and store 32

bits (4 bytes). Unlike standard longs, unsigned longs will not store negative numbers,

making their range from 0 to 4,294,967,295 (2^32 - 1).

Short A short is a 16-bit data-type. On all Arduinos (ATMega and ARM based), a short

store a 16-bit (2-byte) value. This yields a range of -32,768 to 32,767 (minimum value of -2^15 and a maximum value of (2^15) - 1).

float

Data type for floating-point number is a number that has a decimal point. Floating-point numbers are often used to approximate the analog and continuous values because they have greater resolution than integers.

Floating-point numbers can be as large as 3.4028235E+38 and as low as -3.4028235E+38. They are stored as 32 bits (4 bytes) of information.

double On the Uno and other ATMEGA based boards, Double precision floating-point number occupies four bytes. That is, the double implementation is exactly the same as the float, with no gain in precision. On the Arduino Due, doubles have 8-byte (64 bit) precision.

`


4.3 Programming Structure

Sketch − The first new terminology is the Arduino

program called “sketch”. A sketch is the name that

Arduino uses for a program. It is the unit of code that is

uploaded to and run on an Arduino board.

Structure

Arduino programs can be divided in

three main parts: Structure, Values

(variables and constants), and Functions. In

this tutorial, we will learn about the Arduino

software program, step by step, and how we

can write the program without any syntax or

compilation error.

Let us start with the Structure. Software

structure consist of two main functions −

a. Setup( ) function

b. Loop( ) function

a. Void setup ( )

Purpose − The setup() function is called when a sketch starts. Use it to initialize the

variables, pin modes, start using libraries, etc. The setup function will only run once, after

each power up or reset of the Arduino board.

INPUT – no input

OUTPUT – no output

RETURN – returns void

b. void Loop ( )

Purpose − After creating a setup() function, which

initializes and sets the initial values, the loop()

function does precisely what its name suggests, and

loops consecutively, allowing your program to change

and respond. Use it to actively control the Arduino

board.

INPUT – no input

OUTPUT – no output

RETURN – returns void

`


pinMode(3,INPUT) ; // set pin to input without using built in pull up resistor pinMode(5,INPUT_PULLUP) ; // set pin to input using built in pull up resistor

4.4 Digital I/O Programming The pins on the Arduino board can be configured as either inputs or outputs. It is

important to note that a majority of Arduino analog pins, may be configured, and used, in

exactly the same manner as digital pins.

Pins Configured as INPUT

Arduino pins are by default configured as

inputs, so they do not need to be explicitly

declared as inputs with pinMode() when you are

using them as inputs. Pins configured this way are

said to be in a high-impedance state. Input pins

make extremely small demand on the circuit that

they are sampling, equivalent to a series resistor

of 100 megaohm at the pin.

This means that it takes very little current

to switch the input pin from one state to another. This makes the pins useful for such tasks

as implementing a capacitive touch sensor or reading an LED as a photodiode.

Pins configured as pinMode(pin, INPUT) with nothing connected to them, or with

wires connected to them that are not connected to other circuits, report seemingly

random changes in pin state, picking up electrical noise from the environment, or

capacitively coupling the state of a nearby pin.

Pull-up Resistors

Pull-up resistors are often useful to steer an input pin to a known state if no input is present. This can be done by adding a pull-up resistor (to +5V), or a pull-down resistor (resistor to ground) on the input. A 10K resistor is a good value for a pull-up or pull-down resistor.

Using Built-in Pull-up Resistor with Pins

Configured as Input

`


There are 20,000 pull-up resistors built into the Atmega chip that can be accessed

from software. These built-in pull-up resistors are accessed by setting the pinMode() as

INPUT_PULLUP. This effectively inverts the behavior of the INPUT mode, where HIGH

means the sensor is OFF and LOW means the sensor is ON. The value of this pull-up

depends on the microcontroller used. On most AVR-based boards, the value is guaranteed

to be between 20kΩ and 50kΩ. On the Arduino Due, it is between 50kΩ and 150kΩ. For

the exact value, consult the datasheet of the microcontroller on your board.

When connecting a sensor to a pin configured with INPUT_PULLUP, the other end

should be connected to the ground. In case of a simple switch, this causes the pin to read

HIGH when the switch is open and LOW when the switch is pressed. The pull-up resistors

provide enough current to light an LED dimly connected to a pin configured as an input. If

LEDs in a project seem to be working, but very dimly, this is likely what is going on.

Same registers (internal chip memory locations) that control whether a pin is HIGH

or LOW control the pull-up resistors. Consequently, a pin that is configured to have pull-up

resistors turned on when the pin is in INPUTmode, will have the pin configured as HIGH if

the pin is then switched to an OUTPUT mode with pinMode(). This works in the other

direction as well, and an output pin that is left in a HIGH state will have the pull-up resistor

set if switched to an input with pinMode().

Pins Configured as OUTPUT

Pins configured as OUTPUT with pinMode() are said to be in a low-impedance state.

This means that they can provide a substantial amount of current to other circuits. Atmega

pins can source (provide positive current) or sink (provide negative current) up to 40 mA

(milliamps) of current to other devices/circuits. This is enough current to brightly light up

an LED (do not forget the series resistor), or run many sensors but not enough current to

run relays, solenoids, or motors.

Attempting to run high current devices from the output pins, can damage or destroy

the output transistors in the pin, or damage the entire Atmega chip. Often, this results in a

"dead" pin in the microcontroller but the remaining chips still function adequately. For this

reason, it is a good idea to connect the OUTPUT pins to other devices through 470Ω or 1k

resistors, unless maximum current drawn from the pins is required for a particular

application.

`


pinMode() Function Syntax

void setup ()

pinMode (pin , mode);

• pin − the number of the pin whose mode you wish to set

• mode − INPUT, OUTPUT, or INPUT_PULLUP.

digitalWrite() Function Syntax void loop() digitalWrite (pin ,value);

• pin − the number of the pin whose mode you wish to set • value − HIGH, or LOW.

pinMode() Function

The pinMode() function is used to configure a specific pin to behave either as an

input or an output. It is possible to enable the internal pull-up resistors with the mode

INPUT_PULLUP. Additionally, the INPUT mode explicitly disables the internal pull-ups.

digitalWrite() Function

The digitalWrite() function is used to write a HIGH or a LOW value to a digital pin. If

the pin has been configured as an OUTPUT with pinMode(), its voltage will be set to the

corresponding value: 5V (or 3.3V on 3.3V boards) for HIGH, 0V (ground) for LOW. If the pin

is configured as an INPUT, digitalWrite() will enable (HIGH) or disable (LOW) the internal

pullup on the input pin. It is recommended to set the pinMode() to INPUT_PULLUP to

enable the internal pull-up resistor.

If you do not set the pinMode() to OUTPUT, and connect an LED to a pin, when

calling digitalWrite(HIGH), the LED may appear dim. Without explicitly setting pinMode(),

digitalWrite() will have enabled the internal pull-up resistor, which acts like a large

current-limiting resistor.

`


digitalRead() Function Syntax

void loop()

digitalRead(pin)

• pin − the Arduino pin number you want to read

• value − HIGH, or LOW.

int ledPin = 13; // LED connected to digital pin 13

int inPin = 7; // pushbutton connected to digital pin 7

int val = 0; // variable to store the read value

void setup()

pinMode(ledPin, OUTPUT); // sets the digital pin 13 as output

pinMode(inPin, INPUT); // sets the digital pin 7 as input

void loop()

val = digitalRead(inPin); // read the input pin

digitalWrite(ledPin, val); // sets the LED to the button's value

int LED = 6; // LED connected to pin 6

void setup ()

pinMode(LED, OUTPUT); // set the digital pin as output

void loop ()

digitalWrite(LED, HIGH); // turn on led

delay(500); // delay for 500 ms

digitalWrite(LED, LOW); // turn off led


digitalRead() Function

Reads the value from a specified digital pin, either HIGH or LOW.

`


int button = 5 ; // button connected to pin 5

int LED = 6; // LED connected to pin 6

void setup () pinMode(button , INPUT_PULLUP);

// set the digital pin as input with pull-up resistor

pinMode(button , OUTPUT); // set the digital pin as output

void loop ()

If (digitalRead(button ) == LOW) // if button pressed

digitalWrite(LED,HIGH); // turn on led


digitalWrite(LED,LOW); // turn off led


4.5 Analog I/O Programming

analogRead( ) function

Arduino is able to detect whether there

is a voltage applied to one of its pins and

report it through the digitalRead() function.

There is a difference between an on/off sensor

(which detects the presence of an object) and

an analog sensor, whose value continuously

changes. In order to read this type of sensor,

we need a different type of pin.

In the lower-right part of the Arduino

board, you will see six pins marked “Analog

In”. These special pins not only tell whether there is a voltage applied to them, but also its

value. By using the analogRead() function, we can read the voltage applied to one of the

pins.

`


analogRead() function Syntax

Void loop()

analogRead(pin);

• pin − the number of the analog input pin to read from (0 to 5 on most boards, 0 to 7 on the Mini and Nano, 0 to 15 on the Mega)

int analogPin = 3;//potentiometer wiper (middle terminal)

// connected to analog pin 3

int val = 0; // variable to store the value read

void setup()

Serial.begin(9600); // setup serial

void loop()

val = analogRead(analogPin); // read the input pin

Serial.println(val); // debug value

This function returns a number between 0 and 1023, which represents voltages between 0

and 5 volts. For example, if there is a voltage of 2.5 V applied to pin number 0,

analogRead(0) returns 512.

analogWrite( ) function

Writes an analog value (PWM wave) to a pin. Can be used to light a LED at varying brightness’s or drive a motor at various speeds. After a call to analogWrite(), the pin will generate a steady rectangular wave of the specified duty cycle until the next call to analogWrite() (or a call to digitalRead() or digitalWrite()) on the same pin.

You do not need to call pinMode() to set the pin as an output before calling

analogWrite(). The analogWrite() function has nothing to do with the analog pins or the analogRead function.

`


analogWrite() function Syntax

void loop()

analogWrite(pin, value)

• pin: the Arduino pin to write to. Allowed data types: int.

• value: the duty cycle: between 0 (always off) and 255 (always on). Allowed data types: int.

Example

int ledPin = 9; // LED connected to digital pin 9

int analogPin = 3; // potentiometer connected to analog pin 3


void setup()

pinMode(ledPin, OUTPUT); // sets the pin as output

void loop()


analogWrite(ledPin, val / 4); // analogRead values go from 0 to 1023, analogWrite

values from 0 to 255

Notes and Warnings: The PWM outputs generated on pins 5 and 6 will have higher-than-

expected duty cycles. This is because of interactions with the millis() and delay() functions,

which share the same internal timer used to generate those PWM outputs. This will be

noticed mostly on low duty-cycle settings (e.g. 0 - 10) and may result in a value of 0 not

fully turning off the output on pins 5 and 6.

`


analogReference () function Syntax

analogReference (type);

analogReference() Function

Configures the reference voltage used for analog input (i.e. the value used as the

top of the input range). The options are –

DEFAULT − The default analog reference of 5 volts (on 5V Arduino boards) or 3.3 volts

(on 3.3V Arduino boards)

INTERNAL − A built-in reference, equal to 1.1 volts on the ATmega168 or ATmega328

and 2.56 volts on the ATmega8 (not available on the Arduino Mega)

INTERNAL1V1 − A built-in 1.1V reference (Arduino Mega only)

INTERNAL2V56 − A built-in 2.56V reference (Arduino Mega only)

EXTERNAL − The voltage applied to the AREF pin (0 to 5V only) is used as the reference

type − can use any type of the follow (DEFAULT, INTERNAL, INTERNAL1V1, INTERNAL2V56,

EXTERNAL)

Do not use anything less than 0V or more than 5V for external reference voltage on the

AREF pin. If you are using an external reference on the AREF pin, you must set the analog

reference to EXTERNAL before calling the analogRead() function. Otherwise, you will short

the active reference voltage (internally generated) and the AREF pin, possibly damaging

the microcontroller on your Arduino board.

Alternatively, you can connect the external reference voltage to the AREF pin

through a 5K resistor, allowing you to switch between external and internal reference

voltages.

Note that the resistor will alter the voltage that is used as the reference because

there is an internal 32K resistor on the AREF pin. The two acts as a voltage divider. For

example, 2.5V applied through the resistor will yield 2.5 * 32 / (32 + 5) = ~2.2V at the AREF

pin.

`


int analogPin = 3; // potentiometer wiper (middle terminal) connected to analog pin 3


void setup()

Serial.begin(9600); // setup serial

analogReference(EXTERNAL); // the voltage applied to the AREF pin (0 to 5V only)

// is used as the reference.

void loop()


Serial.println(val); // debug value

4.6 Serial Data Monitoring Serial Communication Modules: Today, most Arduino boards are built with several

different systems for serial communication as standard equipment.

Which of these systems are used depends on the following factors –

• How many devices the microcontroller has to exchange data with? • How fast the data exchange has to be? • What is the distance between these devices? • Is it necessary to send and receive data simultaneously?

One of the most important things concerning serial communication is the Protocol,

which should be strictly observed. It is a set of rules, which must be applied such that the

devices can correctly interpret data they mutually exchange. Fortunately, Arduino

automatically takes care of this, so that the work of the programmer/user is reduced to

simple write (data to be sent) and read (received data).

Types of Serial Communications

Serial communication can be further classified as −

a. Synchronous − Devices that are synchronized use the same clock and their timing is

in synchronization with each other.

b. Asynchronous − Devices that are asynchronous have their own clocks and are

triggered by the output of the previous state.

`


It is easy to find out if a device is synchronous or not. If the same clock is given to all the

connected devices, then they are synchronous. If there is no clock line, it is asynchronous.

For example, UART (Universal Asynchronous Receiver Transmitter) module is

asynchronous.

The asynchronous serial protocol has a number of built-in rules. These rules are nothing

but mechanisms that help ensure robust and error-free data transfers. These mechanisms,

which we get for eschewing the external clock signal, are –

Synchronization bits Data bits Parity bits Baud rate Synchronization Bits

The synchronization bits are two or three special bits transferred with each packet of

data. They are the start bit and the stop bit(s). True to their name, these bits mark the

beginning and the end of a packet respectively.

There is always only one start bit, but the number of stop bits is configurable to either

one or two (though it is normally left at one).

The start bit is always indicated by an idle data line going from 1 to 0, while the stop

bit(s) will transition back to the idle state by holding the line at 1.

Data Bits

The amount of data in each packet can be set to any size from 5 to 9 bits. Certainly,

the standard data size is your basic 8-bit byte, but other sizes have their uses. A 7-bit data

packet can be more efficient than 8, especially if you are just transferring 7-bit ASCII

characters.

Parity Bits

The user can select whether there should be a parity bit or not, and if yes, whether

the parity should be odd or even. The parity bit is 0 if the number of 1’s among the data

bits is even. Odd parity is just the opposite.

Baud Rate

The term baud rate is used to denote the number of bits transferred per second

[bps]. Note that it refers to bits, not bytes. It is usually required by the protocol that each

byte is transferred along with several control bits. It means that one byte in serial data

stream may consist of 11 bits. For example, if the baud rate is 300 bps then maximum 37

`


void setup()

Serial.begin(9600); //set up serial library baud rate to 9600

Serial.println("hello world"); //print hello world

void loop()

void setup()

Serial.begin(9600); //set up serial library baud rate to 9600

void loop()

if(Serial.available()) //if number of bytes (characters) available for

reading from

serial port

Serial.print("I received:"); //print I received

Serial.write(Serial.read()); //send what you read

and minimum 27 bytes may be transferred per second.

Arduino UART

The following code will make Arduino send hello world when it starts up.

After the Arduino sketch has been uploaded to Arduino, open the Serial monitor at the top right section of Arduino IDE.

Type anything into the top box of the Serial Monitor and press send or enter on your keyboard. This will send a series of bytes to the Arduino.

The following code returns whatever it receives as an input.

The following code will make Arduino deliver output depending on the input

provided.

Notice that Serial.print and Serial.println will send back the actual ASCII code, whereas

Serial.write will send back the actual text. See ASCII codes for more information.

Reference: https://www.tutorialspoint.com/arduino/

https://www.tutorialspoint.com/arduino/

`


5.0 IoT (Internet of Things)

Introduction: IoT stands for

Internet of Things, which

means accessing and

controlling daily usable

equipment’s and devices using

Internet. This Chapter includes

all topics of IoT such as

introduction, features,

advantage and disadvantage,

ecosystem, decision

framework, architecture and

domains, biometric, security camera and door unlock system, devices, etc. The term "the

Internet of things" was coined by Kevin Ashton of Procter & Gamble, later MIT's Auto-ID

Center, in 1999.

An IOT can:

• Can connect to the Internet

• Talk with other devices

• Collect and send data to the servers

• Do physical changes as per given commands

5.1 Internet of Things (IoT)

Let's us look closely at the mobile device which contains GPS Tracking, Mobile

Gyroscope, Adaptive brightness, Voice detection, Face detection etc. These components

have their own individual features, but what about if these all communicate with each

other to provide a better environment? For example, the phone brightness is adjusted

based on my GPS location or my direction.

Connecting everyday things embedded with electronics, software, and sensors to

internet enabling to collect and exchange data without human interaction is called as the

Internet of Things (IoT). The term "Things" in the Internet of Things refers to anything and

everything in day to day life which is accessed or connected through the internet.

IoT is an advanced automation and analytics system which deals with artificial

intelligence, sensor, networking, electronic, cloud messaging etc. to deliver complete

systems for the product or services. The system created by IoT has greater transparency,

control, and performance.

`


As we have a platform such as cloud that contains all the data through which we

connect all the things around us. For example, a house, where we can connect our home

appliances such as air conditioner, light, etc. through each other and all these things are

managed at the same platform. Since we have a platform, we can connect our car, track its

fuel meter, speed level, and also track the location of the car.

"The cloud" refers to servers accessed over the Internet, and the software and databases that

run on those servers. Cloud servers are located in data centers all over the world. By using cloud

computing, users and companies do not have to manage physical servers themselves or run

software applications on their own machines.

The cloud enables users to access the same files and applications from almost any device,

because the computing and storage takes place on servers in a data center, instead of locally on the

user device. This is why a user can log in to their Instagram account on a new phone after their old

phone breaks and still find their old account in place, with all their photos, videos, and conversation

history. It works the same way with cloud email providers like Gmail or Microsoft Office 365, and

with cloud storage providers like Dropbox or Google Drive.

If there is a common platform where all these things can connect to each other it

would be great because based on my preference, I can set the room temperature. For

example, if I love the room temperature to to be set at 25 or 26-degree Celsius when I

reach back home from my office, then according to my car location, my AC would start

before 10 minutes I arrive at home. This can be done through the Internet of Things (IoT).

`


Definition of IoT

Internet of Things (IoT) is a

network of physical objects or

people called "things" that are

embedded with software,

electronics, network, and sensors

that allows these objects to collect

and exchange data.

The Internet of Things (IoT) is the

ability to have devices

communicate with one another

via the internet or other networks,

remotely tracking information to

provide feedback to assist with

decision making for commercial, industrial and residential purposes. This is commonly

done using sensors connecting to a back-to-base system.

How does Internet of Thing (IoT) Work?

The working of IoT is different for different IoT echo

system (architecture). However, the key concept of

there working are similar. The entire working process

of IoT starts with the device themselves, such as

smartphones, digital watches, electronic appliances,

which securely communicate with the IoT platform.

The platforms collect and analyze the data from all

multiple devices and platforms and transfer the most

valuable data with applications to devices.

The Internet of Things (IoT), also sometimes referred to as the Internet of Everything

(IoE), consists of all the web-enabled devices that collect, send and act on data they

acquire from their surrounding environments using embedded sensors, processors and

communication hardware. These devices, often called "connected" or "smart" devices, can

sometimes talk to other related devices, a process called Machine to-Machine (M2M)

communication, and act on the information they get from one another, Humans can

interact with the gadgets to set them up, give them instructions or access the data, but the

devices do most of the work on their own without human intervention. Their existence has

been made possible by all the tiny mobile components that are available these days, as

well as the always-online nature of our home and business networks.

`


Connected devices also generate massive amounts of Internet traffic, including loads of data that can be used to make the devices useful, but can also be mined for other purposes. All this new data, and the Internet-accessible nature of the devices, raises both privacy and security concerns.

WHY IoT?

IoT technology allows for a level of real-time information that

we've never had before. We can monitor our homes and

families remotely to keep them safe. Businesses can improve

processes to increase productivity and reduce material waste

and unforeseen downtime. Sensors in city infrastructure can

help reduce road congestion and warn us when infrastructure is

in danger of crumbling. Gadgets out in the open can monitor for

changing environmental conditions and warn us of impending disasters.

Features of IoT

`The most important features of IoT on which it works are connectivity, analyzing,

integrating, active engagement, and many more. Some of them are listed below:

Connectivity: Connectivity refers to establish a proper

connection between all the things of IoT-to-IoT platform it may

be server or cloud. After connecting the IoT devices, it needs a

high-speed messaging between the devices and cloud to enable

reliable, secure and bi-directional communication.

Analyzing: After connecting all the relevant things, it comes to

real-time analyzing the data collected and use them to build

effective business intelligence. If we have a good insight into data gathered from all these

things, then we call our system has a smart system.

Integrating: IoT integrating the various models to improve the user experience as well.

Artificial Intelligence: IoT makes things smart and enhances life through the use of data.

For example, if we have a coffee machine whose beans are going to end, then the coffee

machine itself orders the coffee beans of your choice from the retailer.

`


Sensing: The sensor devices used in IoT technologies detect and measure any change in

the environment and report on their status. IoT technology brings passive networks to

active networks. Without sensors, there could not hold an effective or true IoT

environment.

Active Engagement: IoT makes the connected technology, product, or services to active

engagement between each other.

Endpoint Management: It is important to do the endpoint management of all the IoT

system, otherwise it causes the complete failure of the system. For example, if a coffee

machine itself orders the coffee beans when it goes to the end but what happens when it

orders the beans from a retailer and we are not present at home for a few days, it leads to

the failure of the IoT system. So, there must be a need for endpoint management.

5.2 Components of IoT

There are 4 fundamental components of IoT system, which tells us how IoT works.

a. Sensors/Devices: Sensors or devices are a key

component that helps us collect live data from the

surrounding environment. All this data may have

various levels of complexities. It could be a simple

temperature monitoring sensor, or it may be in the

form of the video feed.

IoT Components – Sensors/Devices

A device may have various types of sensors which performs multiple tasks apart

from sensing. Example, A mobile phone is a device which has multiple sensors like GPS,

camera but your smartphone is not able to sense these things.

b. Connectivity: All the collected data is sent to a

cloud infrastructure. The sensors should be

connected to the cloud using various mediums of

communications. These communication mediums

include mobile or satellite networks, Bluetooth,

WI-FI, WAN, etc.

`


c. Data Processing: Once that data is collected, and it gets to the cloud,

the software performs processing on the gathered

data. This process can be just checking the

temperature, reading on devices like AC or heaters.

However, it can sometimes also be very complex

like identifying objects, using computer vision on

video.

d. User Interface: The information needs to be

available to the end-user in some way which can be

achieved by triggering alarms on their phones or

sending them notification through email or text

message. The user sometimes might need an

interface which actively checks their IoT system. For

example, the user has a camera installed in his

home. He wants to access video recording and all the feeds with the help of a web server.

Requirements for a Reference Architecture

There are some specific requirements for IoT that are unique to IoT devices and the

environments that support them, e.g., many requirements emerge from the limited form

factors and power available to IoT devices. Other requirements come from the way in

which IoT devices are manufactured and used. The approaches are much more like

traditional consumer product designs than existing Internet approaches. It can summarize

the overall requirements into some key categories.

a. Connectivity and communications

b. Device management

c. Data collection, analysis, and

actuation

d. Scalability

e. Security

f. High Availability (HA)

g. Predictive analysis

h. Integration

`


Form factor for computers refers to the size, shape, and physical specifications of hardware or hardware components. Computer form factor is used to describe any physical aspect of a computer system. One example of a computer form factor is the difference between a desktop and a laptop computer. Although the same parts are present in each, they are shaped and attached differently. For example, the keyboard from a desktop computer cannot fit into the keyboard space of a laptop computer.

a. Connectivity and Communications: Existing protocols, such as HTTP, have a very

important place for many devices. Even an 8-

bit controller can create simple GET and

POST requests and HTTP provides an

important unified and uniform connectivity.

However, the overhead of HTTP and some

other traditional Internet protocols can be

an issue for two main reasons. Firstly, the

memory size of the program can be an issue

on small devices. However, the bigger issue

is the power requirements. In order to meet

these requirements, we need a simple, small and binary protocol. We will look at this in

more detail below. We also require the ability to cross firewalls.

In addition, there are devices that connect directly and those that connect via

gateways. The devices that connect via a gateway potentially require two protocols: one

to connect to the gateway, and then another from the gateway to the cloud.

b. Device Management: While many IoT devices are not actively managed, this is not

necessarily ideal. We have seen active management of PCs, mobile phones, and other

devices become increasingly important, and the same trajectory is both likely and

desirable for IoT devices.

The following list covers some widely desirable requirements:

The ability to disconnect a rogue or stolen

device

The ability to update the software on a device

Updating security credentials

Remotely enabling or disabling certain

hardware capabilities

Locating a lost device

Wiping secure data from a stolen device

Remotely re-configuring Wi-Fi, GPRS, or network parameters

`


c. Data Collection, Analysis, and Actuation: A few IoT devices have some form of UI (User

Interface), but in general IoT devices are focused on offering one or more sensors, one or

more actuators, or a combination

of both. The requirements of the

system are that we can collect

data from very large numbers of

devices, store it, analyze it, and

then act upon it. The reference

architecture is designed to

manage very large numbers of

devices. If these devices are

creating constant streams of data, then this creates a significant amount of data. The

requirement is for a highly scalable storage system, which can handle diverse data and

high volumes.

The action may happen in near real time, so there is a strong requirement for real-

time analytics. In addition, the device needs to be able to analyze and act on data. In some

cases, this will be simple, embedded logic. On more

powerful devices we can also utilize more powerful

engines for event processing and action.

d. Scalability: Any server-side architecture would

ideally be highly scalable, and be able to support

millions of devices all constantly sending, receiving,

and acting on data. However, many “high-scalability

architectures” have come with an equally high price

– both in hardware, software, and in complexity. An important requirement for this

architecture is to support scaling from a small deployment to a very large number of

devices. Elastic scalability and the ability to deploy in a cloud infrastructure are essential.

The ability to scale the server side out on small cheap servers is an important requirement

to make this an affordable architecture for small deployments as well as large ones.

e. Security: Security is one of the most important aspects for

IoT. IoT devices are often collecting highly personal data, and

by their nature are bringing the real world onto the Internet

(and vice versa). This brings three categories of risks:

Risks that are inherent in any Internet system, but that

product/IoT designers may not be aware of.

Specific risks that are unique to IoT devices.

`


Safety to ensure no harm is caused by, for instance, misusing actuators.

The first category includes simple things such as locking down open ports on devices

(like the Internet-attached fridge that had an unsecured SMTP server and was being used

to send spam). The second category includes issues specifically related to IoT hardware,

e.g., the device may have its secure information read. For example, many IoT devices are

too small to support proper asymmetric encryption. Another specific example is the ability

for someone to attack the hardware to understand security. Two very important specific

issues for IoT security are the concerns about identity and access management. Identity is

an issue where there are often poor practices implemented.

This concludes the set of requirements that we have identified for the reference

architecture. Of course, any given architecture may add further requirements. Some of

those may already be met by the architecture, and some may require further components

to be added. However, our design is for a modular architecture that supports extensions,

which copes with this demand.

f. High Availability (HA): High availability (HA) is a deployment in which two firewalls are

placed in a group and their configuration is synchronized to prevent a single point of

failure on your network. A

heartbeat connection between the

firewall peers ensures seamless

failover in the event that a peer

goes down. Setting up two firewalls

in an HA pair provides redundancy

and allows you to ensure business

continuity.

g. Predictive analysis: The most widely advertised use of IoT data for business is regarding

maintenance and seeing when machines or

systems need to be worked on to prevent

problems. A commercial feature an elevator

technician showing up at the office building

to perform work on an elevator before it

breaks. This is predictive analytics over IoT

data. The straightforward logic is if a

particular part or sensor is out of its normal

operating range, then dispatch a technician.

People get that idea. Predictive analytics

`


takes it a step further by examining the trends of those same sensors to predict when it

will exceed normal ranges.

h. Integration: IoT and integration go hand in hand. With IoT, companies are moving more

towards cloud-based systems to bring about their digital transformation. This enables the

two to come together rapidly. Since technology is changing daily, integration needs to

move at an accelerated level and speed. Therefore, with integration and IoT, speedy fusion

comes together instantly. Integration helps capture data from smart devices and move it

into business applications to automate processes, support real-time monitoring and apply

analytics for insights.

5.3 Four Stages of IoT Architecture There are several layers of IoT built upon the capability and performance of IoT elements that provides the optimal solution to the business enterprises and end-users.

`


The IoT architecture is a fundamental way to design the various elements of IoT, so that it can deliver services over the networks and serve the needs for the future. Following are the primary stages (layers) of IoT that provides the solution for IoT architecture.

a. Sensors/Actuators b. Gateways and Data Acquisition c. Edge IT d. Data canter/ Cloud

a. Sensors/Actuators

Sensors or Actuators are the devices that are able to emit, accept and process data

over the network. These sensors or actuators may be connected either through wired or

wireless. This contains GPS, Electrochemical, Gyroscope, RFID, etc. Most of the sensors

need connectivity through sensors gateways. The connection of sensors or actuators can

be through a Local Area Network (LAN) or Personal Area Network.

`


b. Gateways and Data Acquisition: As the large numbers of data are produced by these

sensors and actuators need the high-speed Gateways and Networks to transfer the data.

This network can be of type Local Area Network (LAN such as Wi-Fi, Ethernet, etc.), Wide

Area Network (WAN such as GSM, 5G, etc.).

c. Edge IT: Edge in the IoT Architecture is the hardware and software gateways that

analyze and pre-process the data before transferring it to the cloud. If the data read from

the sensors and gateways are not changed from its previous reading value then it does not

transfer over the cloud, this saves the data used.

d. Data center/ Cloud: The Data Center or Cloud comes under the Management Services

which process the information through analytics, management of device and security

controls. Beside this security controls and device management the cloud transfers the data

to the end user’s application such as Retail, Healthcare, Emergency, Environment, and

Energy, etc.

`


5.4 Architecture of IoT

Major IoT building blocks and layers Before we go any further, it’s worth pointing out that there is no single, agreed-

upon IoT architecture. It varies in complexity and number of architectural layers

depending on a particular business task.

But no matter the use case and number of layers, the key building blocks of any IoT

structure are always the same, namely:

Smart things;

Networks and gateways enabling low-power devices (which is often the case in IoT) to

enter the big Internet;

The middleware or IoT platforms providing data storage spaces and advanced

computing engines along with analytical capabilities; and

Applications, allowing end users to benefit from IoT and manipulate the physical world.

https://www.altexsoft.com/blog/iot-platforms/

`


These elements make up the backbone of any IoT system upon which effective, multi-

layered architecture can be developed. Most commonly, these layers are:

Layer 1 – Physical Devices

Layer 2 – Connectivity

Layer 3 – Edge Computing

Layer 4 – Data Accumulation

Layer 5 – Data Analysis

Layer 6 – Application

Layer 7 – Collaboration & Processes

1. Physical Devices and Controllers: The IoT Reference Model starts with Layer1. It

includes all physical devices and controllers that might control multiple devices. These are

the “things” in the IoT, and they include a wide range of endpoint devices that send and

receive information. Today, the list of devices is already extensive. It will become almost

unlimited as more equipment is added to the IoT over time.

Devices are diverse, and there are no rules about size, location, form factor, or

origin. Some devices will be the size of a silicon chip. Some will be as large as vehicles. The

IoT must support the entire range. Dozens or hundreds of equipment manufacturers will

produce IoT devices. To simplify compatibility and support manufacturability, the IoT

Reference Model generally describes the level of processing needed from Layer 1 devices.

`


2. Connectivity: Communications and connectivity are concentrated in layer 2. The most

important function of Layer 2 is reliable, timely information transmission. This includes

transmissions:

Between devices (Layer 1) and the network

Across networks (east-west)

Between the network (Layer 2) and low-level information processing occurring at

Layer 3

Traditional data communication networks have multiple functions, as evidenced by

the International Organization for Standardization (ISO) 7-layer reference model. However,

a complete IoT system contains many levels in addition to the communications network.

One objective of the IoT Reference Model is for communications and processing to be

executed by existing networks. The IoT Reference Model does not require or indicate

creation of a different network—it relies on existing networks. However, some legacy

devices aren’t IP-enabled, which will require introducing communication gateways. Other

devices will require proprietary controllers to serve the communication function.

However, over time, standardization will increase. As Layer 1 devices proliferate, the ways

in which they interact with Layer 2 connectivity equipment may change. Regardless of the

details, Layer 1 devices communicate through the IoT system by interacting with Layer 2

connectivity.

`


3. Edge (Fog) Computing: The functions of Layer 3 are driven by the need to convert

network data flows into information that is suitable for storage and higher-level processing

at Layer 4 (data accumulation). This means that Layer 3 activities focus on high-volume

data analysis and transformation. For example, a Layer 1 sensor device might generate

data samples multiple times per second, 24 hours a day, 365 days a year. A basic tenet of

the IoT Reference Model is that the most intelligent system initiates information

processing as early and as close to the edge of the network as possible. This is sometimes

referred to as fog computing. Layer 3 is where this occurs.

Given that data is usually submitted to the connectivity level (Layer 2) networking

equipment by devices in small units, Layer 3 processing is performed on a packet-by-

packet basis. This processing is limited, because there is only awareness of data units—not

“sessions” or “transactions.” Layer 3 processing can encompass many examples, such as:

Evaluation: Evaluating data for criteria as to whether it should be processed at a

higher level

Formatting: Reformatting data for consistent higher-level processing

Expanding/decoding: Handling cryptic data with additional context (such as the origin)

Distillation/reduction: Reducing and/or summarizing data to minimize the impact of

data and traffic on the network and higher-level processing systems

Assessment: Determining whether data represents a threshold or alert; this could

include redirecting data to additional destinations.

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4. Data Accumulation: Networking systems are built to reliably move data. The data is “in

motion.” Prior to Layer 4, data is moving through the network at the rate and organization

determined by the devices generating the data. The model is event driven. As defined

earlier, Layer 1 devices do not include computing capabilities themselves. However, some

computational activities could occur at Layer 2, such as protocol translation or application

of network security policy. Additional compute tasks can be performed at Layer 3, such as

packet inspection. Driving computational tasks as close to the edge of the IoT as possible,

with heterogeneous systems distributed across multiple management domains represents

an example of fog computing. Fog computing and fog services will be a distinguishing

characteristic of the IoT.

`


Most applications cannot, or do not need to, process data at network wire speed. Applications typically assume that data is “at rest”—or unchanging—in memory or on disk. At Layer 4, Data Accumulation, data in motion is converted to data at rest. Layer 4 determines: If data is of interest to higher levels: If so, Layer 4 processing is the first level that is

configured to serve the specific needs of a higher layer. If data must be persisted: Should data be kept on disk in a non-volatile state or

accumulated in memory for short-term use? The type of storage needed: Does persistency require a file system, big data system,

or relational database? If data is organized properly: Is the data appropriately organized for the required

storage system? If data must be recombined or recomputed: Data might be combined, recomputed, or

aggregated with previously stored information, some of which may have come from non-IoT sources.

As Layer 4 captures data and puts it at rest, it is now usable by applications on a non-

real-time basis. Applications access the data when necessary. In short, Layer 4 converts event-based data to query-based processing. This is a crucial step in bridging the differences between the real-time networking world and the non-real-time application world. 5. Data Abstraction: IoT systems will need to scale to a corporate—or even global—level

and will require multiple storage systems to accommodate IoT device data and data from

traditional enterprise ERP, HRMS, CRM, and other systems. The data abstraction functions

of Layer 5 are focused on rendering data and its storage in ways that enable developing

simpler, performance-enhanced applications.

`


With multiple devices generating data, there are many reasons why this data may not land

in the same data storage:

There might be too much data to put in one place.

Moving data into a database might consume too much processing power, so that

retrieving it must be separated from the data generation process. This is done today

with online transaction processing (OLTP) databases and data warehouses.

Devices might be geographically separated, and processing is optimized locally.

Layer 3 and 4 might separate “continuous streams of raw data” from “data that

represents an event.” Data storage for streaming data may be a big data system, such

as Hadoop. Storage for event data may be a relational database management system

(RDBMS) with faster query times.

Different kinds of data processing might be required. For example, in-store processing

will focus on different things than across-all-stores summary processing.

For these reasons, the data abstraction level must process many different things. These

include:

Reconciling multiple data formats from different sources

Assuring consistent semantics of data across sources

Confirming that data is complete to the higher-level application

Consolidating data into one place (with ETL, ELT, or data replication) or providing

access to multiple data stores through data virtualization

Protecting data with appropriate authentication and authorization

Normalizing or de-normalizing and indexing data to provide fast application access

6. Application: Layer 6 is the application level, where information interpretation occurs.

Software at this level interacts with Layer 5 and data at rest, so it does not have to operate

at network speeds.

The IoT Reference Model does not strictly define an application. Applications vary

based on vertical markets, the nature of device data, and business needs. For example,

some applications will focus on monitoring device data. Some will focus on controlling

devices. Some will combine device and non-device data. Monitoring and control

applications represent many different application models, programming patterns, and

software stacks, leading to discussions of operating systems, mobility, application servers,

hypervisors, multi-threading, multi-tenancy, etc. These topics are beyond the scope of the

IoT Reference Model discussion. Suffice it to say that application complexity will vary

widely.

`


Examples include:

Mission-critical business applications, such as generalized ERP or specialized industry

solutions

Mobile applications that handle simple interactions

Business intelligence reports, where the application is the BI server

Analytic applications that interpret data for business decisions

System management/control center applications that control the IoT system itself and

don’t act on the data produced by it

If Layers 1-5 are architected properly, the amount of work required by Level 6 will be

reduced. If Layer 6 is designed properly, users will be able to do their jobs better.

7. Collaboration and Processes: One of the main distinctions between the Internet of

Things (IoT) and IoT is that IoT includes people and processes. This difference becomes

particularly clear at Layer 7: Collaboration and Processes. The IoT system, and the

information it creates, is of little value unless it yields action, which often requires people

and processes. Applications execute business logic to empower people. People use

applications and associated data for their specific needs. Often, multiple people use the

same application for a range of different purposes. So, the objective is not the

application—it is to empower people to do their work better. Applications (Layer 6) give

business people the right data, at the right time, so they can do the right thing.

But frequently, the action needed requires more than one person. People must be

able to communicate and collaborate, sometimes using the traditional Internet, to make

`


the IoT useful. Communication and collaboration often require multiple steps. And it

usually transcends multiple applications. This is why Layer 7, as shown in Figure,

represents a higher level than a single application.

Security in the IoT

Discussions of security for each level and for the movement of data between levels

could fill a multitude of papers. For the purpose of the IoT Reference Model, security

measures must:

Secure each device or system Provide security for all processes at each level

Secure movement and communication between each level, whether north- or south-

bound.

`


5.5 Industrial IoT – Process, Advantages & Applications

Industrial IoT is a term used to describe machine-to-machine communications

where machines interact with other

machines, objects, and infrastructures

in order to produce data. The huge

volume of data gets generated and that

data gets processed and analyzed by

using technologies like data

analytics and artificial intelligence,

resulting in meaningful actions. It even

makes the use of smart sensors and actuators to enhance the manufacturing processes

and analyze the data in real-time.

Integration of IIoT can give industries a more accurate view of how their operations is

moving along and help them to make decisions fasters and more accurately. Some of the

top companies like IBM Corporation, Intel, Schneider Electric SE, General Electric

Company, and Emerson Electric etc. are implementing Industrial IoT to improve and

optimize their business operations.

Industrial IoT Solutions

Industrial IoT (IIoT) involves collecting and analyzing sensor-generated data to

support equipment monitoring and maintenance, production process analytics and

control, and more. In manufacturing IT since 1989, ScienceSoft offers IIoT consulting and

development to create secure IIoT solutions.

Industrial IoT (IIoT) uses interconnected smart sensors and edge technology in

industrial settings, such as manufacturing, energy, facilities-management, etc. to help

businesses run smoothly and utilize data to improve operations.

Industrial Internet of Things (IIoT)

Interconnected sensors, instruments, and other devices networked together with

computers’ industrial applications, including manufacturing and energy management. It is

important to note that IoT and IIoT have become very ‘buzzwordy’ because the goal is to

create a completely automated, smart factory, but for many manufacturers, that isn’t in

reach because of high costs in both dollars and time, at least for the next few years.

The industrial internet of things (IIoT) is the use of smart sensors and actuators to

enhance manufacturing and industrial processes. Also known as the industrial internet or

Industry 4.0, IIoT uses the power of smart machines and real-time analytics to take

advantage of the data that "dumb machines" have produced in industrial settings for

https://www.spec-india.com/tech-in-200-words/what-is-data-analytics

https://www.spec-india.com/tech-in-200-words/what-is-data-analytics

https://www.sensrtrx.com/manufacturing-software-smart-factory/

https://searchcio.techtarget.com/definition/smart-machines

`


years. The driving philosophy behind IIoT is that smart machines are not only better than

humans at capturing and analyzing data in real time, but they're also better at

communicating important information that can be used to drive business decisions faster

and more accurately.

Connected sensors and actuators enable companies to pick up on inefficiencies and

problems sooner and save time and money, while supporting business intelligence efforts.

In manufacturing, specifically, IIoT holds great potential for quality control, sustainable and

green practices, supply chain traceability, and overall supply chain efficiency. In an

industrial setting, IIoT is key to processes such as predictive maintenance, enhanced field

service, energy management and asset tracking.

How does IIoT work?

IIoT is a network of intelligent devices connected to form systems that monitor,

collect, exchange and analyze data. Each industrial IoT ecosystem consists of

Connected devices that can sense, communicate and store information about

themselves

Public and/or private data communications infrastructure

Analytics and applications that generate business information from raw data

Storage for the data that is generated by the IIoT devices and

People.

These edge devices and intelligent assets transmit information directly to the data

communications infrastructure, where it's converted into actionable information on how a

certain piece of machinery is operating. This information can be used for predictive

maintenance, as well as to optimize business processes.

Uses, Applications & Benefits of Industrial IoT in Manufacturing

The introduction of IoT has opened gates for multitude of possibilities of performance upgrades through total control. IoT has moved out from our homes and offices to the industrial segment, and hence known to become IIoT (Industrial Internet of Things). Industrial IoT in manufacturing industry is a core element of the transformation, and by far it has seen the most investment, which makes for a promising future.

https://whatis.techtarget.com/definition/predictive-maintenance-PdM

https://internetofthingsagenda.techtarget.com/definition/Internet-of-Things-IoT

https://searchnetworking.techtarget.com/definition/edge-device

`


Manufacturing is poised to keep

that first position across the globe

until at least 2020, even if, in some

geographies, this leading position

is more prominent. The

manufacturing industry is leading

in the Internet of Things for

various reasons, such as the

promising industrial revolution

(Industry 4.0) and then there are

the many cases of actual IoT

deployments that offer rapid

return and enable manufacturers to realize digital transformations from several

perspectives: efficiency, automation, customer-centricity, competitive benefits and the

advantages which are offered by using data across the manufacturing value chain and to

tap into new revenue sources, which is a key aspect of industry 4.0 in manufacturing.

1. Inventory Management: Monitoring of events across the supply chain is now possible

through IoT Application. Using these systems, the inventory is tracked across the globe on

a line-item level and the users are notified of any significant deviations from the plans, or

even updates. This provides cross-channel visibility into inventories and managers are

provided with realistic estimates of the available material, work in progress and the

estimated arrival time of new materials. Ultimately this optimizes supply and reduces

shared costs in the value chain.

2. Quality Control: IoT sensors collect aggregate product data and other third-party

syndicated data from various stages of a product cycle. This data relates to the complete

composition of raw materials used, temperature and working environment, wastes, the

impact of transportation and more on the final products. Moreover, if used in the final

product, the IoT device can provide data about the customer sentiments on using the

product. All of these inputs can later be analyzed to identify and correct quality issues,

which leads to significant improvement.

3. Enhanced Safety: Big Data analysis is effectively possible with Industrial Internet of

Things. Key performance indicators of health and safety, such as number of injuries, short-

and long-term absences, illness rates, near-misses, can thus be monitored constantly to

ensure better workplace conditions. Lagging indicators like the number of accidents can be

addressed immediately.

https://www.analyticsinsight.net/how-iot-and-big-data-analytics-is-revolutionizing-manufacturing/

`


4. Smart Metering: IIoT has seen to the introduction of various smart meters. These Smart

meters can monitor the consumption of resources like electricity, fuels, water etc. Through

the use of IoT sensors, manufacturers will know exactly how much is consumed and what

for. Through effective management, operational expenditure can be reduced significantly.

5. Predictive Maintenance: It is the era of preventive maintenance, with Industrial IoT in

Manufacturing we have not only seen a revolution in the machine maintenance system,

but also its delivery. For the first time, predictive maintenance is delivered through

hardware, which takes machine health monitoring beyond cloud computing, into edge

computing. This means faster processing and on spot analysis. Infinite Uptime, which is

ranked amongst the top 25 IoT solutions provider globally, is the only company providing it

through their patented technology. Predictive maintenance (PdM) techniques are

designed to help determine the condition of equipment’s in order to predict when

maintenance should be performed or possible breakdowns. This promises cost savings

over routine or time-based preventive maintenance, as the tasks are performed only when

warranted.

6. Smart Packaging: By using IoT sensors in products and packaging, manufacturers can

gain valuable insights into the usage patterns and handling of product from multiple

customers. Smart tracking mechanisms can be used to track product deterioration during

transit and impact of weather, road and other environment variables on the product. This

in turn offers insights that can be used to re-engineer products and packaging for better

performance in both customer experience and at times, even the cost of packaging.

7. Digital Industries: IoT enabled machinery can transmit operational information to the

partners like OEMs (original equipment manufacturers) and to field engineers. This will

enable operation managers and factory heads to remotely manage the factory units and

take advantage of process automation and optimization. This makes streamlining the day-

to-day work effortless.

Industrial IoT in Manufacturing is indeed empowering the industrial revolution

(industry 4.0). Top companies have been the beneficiaries of integrating IoT enabled

services, the list of the names include Amazon, Hitachi, John Deere, Komatsu, Maersk and

many more.

https://www.infinite-uptime.com/

`


Advantages of Using IIoT

IIoT increases productivity, efficiency, decision-making, reduce the cost and enable

an organization with real-time information and operational benefits. Some of the benefits

are:

1. Reduces the downtime of Machines: When thinking about the most benefit of IIOT,

improvising machine failure comes on the top of the list. Unplanned downtime/machine

breakdown is likely to occur in the manufacturing industry, which reduces their overall

productivity, customer service, and affecting the business as a whole. If manufacturing

industries invest in the Industrial Internet of Things (IIoT), they can gain real-time

information about assets and production processes.

The specialized sensors deployed at every point, track all the parameters of the

individual device and gains granular visibility across the operations. The availability of real-

time machine data enables manufacturers to react to machine failures.

2. Easy tracking and monitoring of Goods: Tracking is another perk of Industrial IoT.

Manufacturers can receive insights in a way customers handle products through the use of

IoT sensors in products and packaging. Suppliers, manufacturers, and customers can use

smart tracking tools to track the goods that may be damaged during transit, track the

location, status, and condition throughout the supply chain. The real-time insights can help

the managers to know if goods are damaged or at risk and can take immediate action to fix

it.

3. Provides condition-based Alerts: The sensors deployed inside the manufacturing

equipment triggers the alerts based on specific conditions like certain temperature or

min/max vibration range. Whenever the equipment deviates from its prescribed

parameters, IoT sensors that are actively monitoring the machines sends alerts. This alert

helps the manufacturers to conserve energy, increase operational efficiency and ensures

that machines are working in their specified parameters.

4. Minimizes Human Errors: Human error is likely to occur where manual operations are

involved. This not only leads to hassle but also leads to serious problems like lost profits or

any emergency situation. IIoT applications can reduce and prevent errors in inventory

management, operational management, and production flow. With IIoT applications, tasks

are automated and there is less human intervention; companies can improve the quality,

monitor events across the supply chain and track inventory across the globe.

`


IIoT Applications

1. Facility Management

2. Production Flow Monitoring

3. Inventory Management

4. Logistics and Supply Chain Optimization

5. Industrial Automation

6. Smart Robotics

7. Autonomous Vehicles

8. Power Management

9. Smart City Applications

10. Smart Farming and Live Stock Monitoring

11. Energy Consumption Optimization

12. Automated and remote equipment management and monitoring

13. Predictive maintenance

14. Faster implementation of improvements

15. Quality control

16. Plant safety improvement

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