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Wireless Notice Board 1
Dept. of Telecommunication Engg. SIT, Tumkur
INTRODUCTION
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Chapter 1
INTRODUCTION
Wireless systems are gaining popularity rapidly, as people attempt to do
away with complicate and confusing wiring operations. Using existing
radio wave frequencies, battery operated control panels allow for easier
operation and maintenance of the display system.
1.1 Wireless Notice Board
Wireless notice board is an enhanced technology used in order to save time
and convey the message with no delay. It provides a wireless data transfer
capability between the hex keypad and the notice board without the need of
wiring on through a radio frequency link.
This is a microcontroller based Embedded System which achieves wireless
interface between a hex keypad and a Notice board. Here a 16x2 alphanumeric
display can be used as the notice board .The user can type the messages to be
displayed in the remote LCD using the hex keypad and can be sent to the notice
board using the ZigBee module. The 8051 microcontroller (P89V51RD2)
based embedded system connected to the hex keypad receives the data typed
on it and sends it to the display system through the wireless link. At the displayside another 8051 microcontroller (P89V51RD2) based embedded system
receives the data through the ZigBee receiver and sends to the display side.
1.2 Need for Wireless Notice Board
Time saving: We can deliver the message instantly to any remote
destination and as it is displayed in general the time is saved.
Convenient: since the message is displayed in common it becomes
economical and the delay in the message delivery is avoided.
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Procedure:
y Determining the requirements of the embedded systemy Designing the system architecturey Choosing the processor and the associated peripheralsy Choosing the development platformy Coding the application and optimizing the codey Verification of the software on the host systemy Circuit Designingy PCB Layouty Device Testy Verification of the software on the target systemy
Documentation
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BLOCK DIAGRAM OF WNB
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Chapter 2
BLOCK DIAGRAM OF WNB
2.1 BLOCK DIAGRAM OF TRANSMITTER
Antenna
Figure 1 Transmitter and Power section
Power supply to all sect
Stepdown
T/F
BridgeRectifier
FilterCircuit
Regulator
MAX
232
8
0
C
5
1
16 X 2 LCD
CrystalReset
HEX
Key pad
Zigbee
Module
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2.2 BLOCK DIAGRAM OF RECEIVER
Antenna
Figure Receiver and Power section
P
ower supply to all sections
Step
down
T/F
Bridge
Rectifier
Filter
CircuitRegulator
MAX 232
8
0
C
5
1
16 X 2 LCD
Cr stal Reset
Zigbee
Module
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1.3 BLOCK DIAGRAM DESCRIPTION
Keypad:
This Keypad Mini Board includes 16 keys for Hex or standard Numeric Data Entry.Positive contact tactile switches are included in a standard matrix arrangement. An 8-bit data
bus is required for pulsing and monitoring the keys.
Pull-Up resistors are included, together with a standard easy to connect IDCC
connector for interfacing. This board can be used with any microcontroller, with each pin
separately polled or by using a series of interrupt pins to monitor the keys.
The Keypad Mini Board will work with any of our controllers and is an easy to use
solution for data entry or simply as a series of switches.
Features
* 16 Keys Included for Hex and Numeric Input
* Keys Arranged in Standard Matrix Format
* Pull-Up Resistors Included
* Standard IDCC connector for easy connection
* Compact and Easy To Mount
* Ideal for use with all our Development and Control Boards
* Board Dimensions: 45 x 55 mm
Microcontroller:
The microprocessor is the core of computer systems. Nowadays many
communication, digital entertainment, portable devices, are controlled by them. A designer
should know what types of components he needs, ways to reduce production costs and
product reliable. In this project we are using 8051 microcontroller.
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Alphanumeric Display (LCD):
LCD stands for Liquid Crystal Displays. "Liquid crystal" is neither solid nor liquid
(an example is soapy water).Liquid crystals when stimulated by an external electrical charge
will change the properties of light passing through the crystals. There are two ways toproduce a liquid-crystal image with such cells: the segment driving method and the matrix
driving method. The segment driving method displays characters and pictures with cells
defined by patterned electrodes. The matrix driving method displays characters and pictures
in sets of dots. In our project we are using 16x2 line matrix driven method display to display
our messages.
Transmitter:
Remote diagnosis ZigBee is a communications standard that provides a Wireless
autopilot control short-range cost effective networking capability. It has been developed
with the emphasis on low-cost battery National Marine Electronics powered applications,
such as, building automation, Association standard data industrial and commercial
controls, marine wireless, over ZigBee personal healthcare and advanced tagging. ZigBee
has been introduced by the IEEE and the ZigBee Alliance to security provide the first general
standard for these applications.
Receiver:
Remote diagnosis ZigBee is a communications standard that provides a Wireless
autopilot control short-range cost effective networking capability. It has been developed
with the emphasis on low-cost battery National Marine Electronics powered applications,
such as, building automation, Association standard data industrial and commercial
controls, marine wireless, over ZigBee personal healthcare and advanced tagging. ZigBee
has been introduced by the IEEE and the ZigBee Alliance to Security provide the first general
standard for these applications.
Power:
In this project the microcontroller requires +5v power supply. The designdescription
of power supply is given above.
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HARDWARE DETAILS
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Chapter 3
HARDWARE DETAILS
3.1 Alphanumeric Display (LCD)
In recent years the LCD is finding widespread use due to the following reasons:
1. The declining prices of LCDs.2. The ability to display numbers, characters and graphics.3. Incorporation of a refreshing controller into the LCD, thereby relieving the CPU of the
task of refreshing the LCD.
4. Ease of programming for characters and graphics.
Figure 3 LCD Interfacing to Microcontroller
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3.1.1 LCD Pin Descriptions
The LCD discussed in this section has 14 pins. The function of each pin is given in
Table 6.1.0. Figure 6.2a shows the pin positions for various LCDs.
Pin Symbol I/O Description
1 VSS -- Ground
2 VCC -- +5V power supply
3 VEE -- Power supply to control contrast
4 RS I RS=0 to select command register,
RS=1 to select data register
5 R/W I R/W=0 for write,
R/W=1 for read
6 E I/O Enable
7 DB0 I/O The 8-bit data bus
8 DB1 I/O The 8-bit data bus
9 DB2 I/O The 8-bit data bus
10 DB3 I/O The 8-bit data bus
11 DB4 I/O The 8-bit data bus
12 DB5 I/O The 8-bit data bus
13 DB6 I/O The 8-bit data bus
14 DB7 I/O The 8-bit data bus
Table 1 Pin Descriptions for LCD
VCC, VSS and VEE
While VCC, and VSSprovide +5V and ground respectively, VEE is used for controlling
LCD contrast.
RS, Register select
There are two very important registers inside the LCD. The RS pin is used for their
selection as follows. If RS = 0, the instruction command code register is selected, allowing
the user to send a command such as clear display, cursor at home, etc. If RS = 1 the data
register is selected, allowing the user to send data to be displayed on the LCD.
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R/W, Read/Write
R/W input allows the user to write information to the LCD or read information from
it, R/W = 1 when reading : R/W = 0 when writing.
E, enableThe enable pin is used by the LCD to latch information presented to its data pins.
When data is supplied to data pins, a high-to-low pulse must be applied to this pin in order
for the LCD to latch in the data present at the data pins. This pulse must be a minimum of
450 ns wide.
Code (Hex) Command to LCD Instruction Register
1 Clear display screen
2 Return home
4 Decrement cursor (shift cursor to left)
6 Increment cursor (shift cursor to right)
5 Shift display right
7 Shift display left
8 Display off, cursor off
A Display off, cursor on
C Display on, cursor off
E Display on, cursor blinking
F Display on, cursor blinking
10 Shift cursor position to left
14 Shift cursor position to right
18 Shift the entire display to the left
1C Shift the entire display to the right
80 Force cursor to beginning of 1st line
C0 Force cursor to beginning of 2nd
line
Table 2 LCD Command Codes
D0 D7
The 8-bit data pins, D0 D7, are used to send information to the LCD or read the
contents of the LCDs internal registers.
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To display letters and numbers, we send ASCII codes for the letters A Z, a z and
number 0 9 to these pins while making RS = 1.
Figure 4-16 x 2 Character LCD Display
Table 3 List of LCD instructions
! "
#
#
#
#
#
#
#
#
#
$
%&
'
'
& &
(
&
')
0
1 "
1
!
2
! 3
#
#
#
#
#
#
#
#
$
4
1 "
1
!
2
! 3
#
#
#
#
#
#
#
$
5
1
!
3 ! 6
(
! "
' "
(
!
7
" !
!
2 7
(
&
' )
#
#
#
#
#
#
$
%
89
8
@ @
!
7
'
& &
(
&
')
A
B
0
1
!
8
9
8
@ @
A
% B
0
' "
(
C &
"
D
!
! "
A
B
#
#
#
#
#
$
%
E
4
4
F
!6
1
!
' "
(
2 7
(
&
')
#
#
#
#
$ E
9
@
4 4
"
7
'
(
'
'
&
" G
2
0 "
13
C
!
7
(
&
')
&
"
0
' "
(
2
' '
7
! "
$ #
5 H I
P H P
'
'
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3.1.2 Addressing Scheme of 2 x 16 LCD
The following table shows the addressing scheme of the 2 x 16 LCD screen.
80 81 82 83 84 85 86 87 88 89 8A 8B 8C 8D 8E 8F
C0 C1 C2 C3 C4 C5 C6 C7 C8 C9 CA CB CC CD CE CF
Table 4 Addressing scheme of the 2 x 16 LCD screen
3.2 DB 9 CONNECTOR
Pin Description
1 Data Carrier Detect (DCD)
2 Received Data (RxD)
3 Transmitted Data (TxD)4 Data Terminal Ready (DTR)
5 Signal Ground (GND)
6 Data Set Ready (DSR)
7 Request to send (RTS)
8 Clear To Send (CTS)
9 Ring Indicator (RI)
Table 5 DB 9 pin description
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3.2.1. DTR (Data Terminal Ready)
When the terminal (or a PC COM port) is turned on, after going through a self-test, it
sends out signal DTR to indicate that it is ready for communication. If there is something
wrong with the COM port, this signal will not be activated.
3.2.2. DSR (Data Set Ready)
When DCE (modem) is turned on and has gone through the self-test, it asserts DSR to
indicate that it is ready to communicate. Thus, it is an output from the modem (DCE) and
input to the PC (DTE). This is an active low signal.
3.2.3. RTS (Request To Send)When the DTE device (such as a PC) has a byte to transmit, it asserts RTS to signal
the modem that it has a byte of data to transmit. RTS is an active-low output from the
DTE and an input to the modem.
3.2.4 CTS (Clear To Send)In response to RTS, when the modem has memory for storing the data it is to receive,
it sends out signal CTS to the DTE (PC) to indicate that it can receive the data now. This
input signal to the DTE is used by the DTE to start transmission. RTS and CTS are also
referred to as hardware control flow signals.
3.2.5. DCD (Carrier detect or Data Carrier Detect).
The modem asserts signal DCD to inform the DTE (PC) that a valid carrier has been
detected and that contact between it and the other modem is established. Therefore, DCD
is an output from the modem and an input to the PC (DTE).
3.2.6. RI (Ring Indicator).
An output from the modem (DCE) and an input to a PC (DTE) indicates that the
telephone is ringing. It goes on and off in synchronization with the ringing sound.
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3.2.7. RxD, TxD and GND.
RxD pin is used to receive data and TxD is used to transmit data serially. GND is the
ground connection for the cable.
3.3 8051 Microcontroller
3.3.1 General description
The P89V51RD2 is an 80C51 microcontroller with 64 KB Flash and 1024 bytes of
data RAM.
A key feature of the P89V51RD2 is its X2 mode option. The design engineer can
choose to run the application with the conventional 80C51 clock rate (12 clocks per machine
cycle) or select the X2 mode (6 clocks per machine cycle) to achieve twice the throughput at
the same clock frequency. Another way to benet from this feature
is to keep the same performance by reducing the clock frequency by half, thus dramatically
reducing the EMI.
The Flash program memory supports both parallel programming and in serial
In-System Programming(ISP). Parallel programming mode offers gang-programming at high
speed, reducing programming costs and time to market. ISP allows a device to be
reprogrammed in the end product under software control. The capability to eld/update the
application rmware makes a wide range of applications possible.
The P89V51RD2 is also In-Application Programmable (IAP), allowing the Flash
program memory to be recongured even while the application is running.
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Fig Pin Layout of AT89C51
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3.3.2 Features
1) 80C51 Central Processing Unit2) 5 V operating voltage from 0 to 40 MHz
3) 64 KB of on-chip Flash program memory with ISP (In-System Programming) and
IAP (In-Application Programming)
4) Supports 12-clock (default) or 6-clock mode selection via software or ISP
PCA (Programmable Counter Array) with PWM and Capture/Compare functions
5) Four 8-bit I/O ports with three high-current Port 1 pins (16 mA each)
6) Three 16-bit timers/counters
7) Programmable Watchdog timer (WDT)
8) Eight interrupt sources with four priority levels
9) Second DPTR register
10) Low EMI mode (ALE inhibit)
11) TTL- and CMOS-compatible logic levels
12) Brown-out detection
13) Low power modes
14) Power-down mode with external interrupt wake-up dle mode
15) PDIP40, PLCC44 and TQFP44 packages
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Figure Circuit Diagram
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Port 0
Port 0 is an 8-bit open-drain bi-directional I/O port. As an output port, each pin can
sink eight TTL inputs. When 1s are written to port 0 pins, the pins can be used as high
impedance inputs. Port 0 may also be configured to be the multiplexed low order
address/data bus during accesses to external program and data memory. In this mode P0 has
internal pull-ups.Port 0 also receives the code bytes during Flash programming, and outputs
the code bytes during program verification. External pull-ups are required during program
verification. With external pull-up resistors connected upon reset, port 0 is configured as an
output port.
Figure 3.2 Port 0 with external pull-up resistors.
Port 1
Port 1 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 1 output
buffers can sink/source four TTL inputs. When 1s are written to Port 1 pins they are pulled
high by the internal pull-ups and can be used as inputs. As inputs, Port 1 pins that are
externally being pulled low will source current (IIL) because of the internal pull-ups. Port 1
also receives the low-order address bytes during Flash programming and verification.
Port 2
Port 2 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 2 output
buffers can sink/source four TTL inputs. When 1s are written to Port 2 pins they are pulled
high by the internal pull-ups and can be used as inputs. As inputs, Port 2 pins that are
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externally being pulled low will source current (IIL) because of the internal pull-ups. Port 2
emits the high-order address byte during fetches from external program memory and during
accesses to external data memory that uses 16-bit addresses (MOVX @ DPTR). In this
application, it uses strong internal pull-ups when emitting 1s. During accesses to external
data memory that uses 8-bit addresses (MOVX @ RI); Port 2 emits the contents of the P2
Special Function Register. Port 2 also receives the high-order address bits and some control
signals during Flash programming and verification.
Port 3:
Port 3 is an 8-bit bi-directional I/O port with internal pull-ups. The Port 3 output
buffers can sink/source four TTL inputs. When 1s are written to Port 3 pins they are pulled
high by the internal pull-ups and can be used as inputs. As inputs, Port 3 pins that are
externally being pulled low will source current because of the pull-ups. Port 3 also serves the
functions of various special features of the AT89C51 as listed in table 3.1.
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Memory organization
The device has separate address spaces for program and data memory.
Flash program memory
There are two internal ash memory blocks in the device. Block 0 has 64 kbytes and contains
the users code. Block 1 contains the Philips-provided ISP/IAP routines and may be enabled
such that it overlays the rst 8 Kbytes of the user code memory. The 64 kB Block 0 is
organized as 512 sectors, each sector consists of 128 bytes. Access to the IAP routines may
be enabled by clearing the BSEL bit in the FCF register. However, caution must be taken
when dynamically changing the BSEL bit. Since this will cause different physical memory to
be mapped to the logical program address space, the user must avoid clearing the BSEL bit
when executing user code within the address range 0000H to 1FFFH.
Data RAM memory
The data RAM has 1024 bytes of internal memory. The device can also address up to 64 kB
for external data memory.
Expanded data RAM addressing
The P89V51RD2 has 1 kB of RAM.
The device has four sections of internal data memory:
1. The lower 128 bytes of RAM (00H to 7FH) are directly and indirectly addressable.
2. The higher 128 bytes of RAM (80H to FFH) are indirectly addressable.
3. The special function registers (80H to FFH) are directly addressable only.
4. The expanded RAM of 768 bytes (00H to 2FFH) is indirectly addressable by the move
external instruction (MOVX) and clearing the EXTRAM bit. Since the upper 128 bytes
occupy the same addresses as the SFRs, the RAM must be accessed indirectly. The RAM and
SFRs space are physically separate even though they have the same addresses.
When instructions access addresses in the upper 128 bytes (above 7FH), the MCU
determines whether to access the SFRs or RAM by the type of instruction given. If it is
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indirect, then RAM is accessed. If it is direct, then an SFR is accessed. See the examples
below.
Indirect Access:
MOV@R0, #data; R0 contains 90H.Register R0 points to 90H which is located in the upper
address range. Data in #data is written to RAM location 90H rather than port 1.
Direct Access:
MOV90H, #data; write data to P1. Data in #data is written to port 1. Instructions that write
directly to the address write to the SFRs. To access the expanded RAM, the EXTRAM bit
must be cleared and MOVX instructions must be used. The extra 768 bytes of memory is
physically located on the chip and logically occupies the rst 768 bytes of external memory
(addresses 000H to 2FFH). When EXTRAM = 0, the expanded RAM is indirectly addressed
using the MOVX instruction in combination with any of the registers R0, R1 of the selected
bank or DPTR. Accessing the expanded RAM does not affect ports P0, P3.6 (WR), P3.7
(RD), or P2. With EXTRAM = 0, the expanded RAM can be accessed as in the following
example. Expanded RAM Access (Indirect Addressing only): MOVX@DPTR, A DPTR
contains 0A0H DPTR points to 0A0H and data in A is written to address 0A0H of the
expanded RAM rather than external memory. Access to external memory higher than 2FFH
using the MOVX instruction will access external memory (0300H to FFFFH) and will
perform in the same way as the standard 8051, with P0 and P2 as data/address bus, and P3.6
and P3.7 as write and read timing signals. When EXTRAM = 1, MOVX @Ri and MOVX
@DPTR will be similar to the standard 8051. Using MOVX @Ri provides an 8-bit address
with multiplexed data on Port 0. Other output port pins can be used to output higher order
address bits. This provides external paging capabilities. Using MOVX @DPTR generates a
16-bit address. This allows external addressing up the 64 kB. Port 2 provides the high-order
eight address bits (DPH), and Port 0 multiplexes the low order eight address bits (DPL) withdata. Both MOVX @Ri and MOVX @DPTR generates the necessary read and write signals
(P3.6 - WR and P3.7 - RD) for external memory use. Table 7 shows external data memory
RD, WR operation with EXTRAM bit. The stack pointer (SP) can be located anywhere
within the 256 bytes of internal RAM (lower 128 bytes and upper 128 bytes). The stack
pointer may not be located in any part of the expanded RAM.
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Dual data pointers
This device has two 16-bit data pointers. The DPTR Select (DPS) bit in AUXR1
determines which of the two data pointers is accessed. When DPS = 0, DPTR0 is
selected; when DPS = 1, DPTR1 is selected. Quickly switching between the two data
pointers can be accomplished by a single INC instruction on AUXR1.
.
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3.3 HEX KEYPAD
Just arrived our new Keypad Mini Board, this board includes 16 keys for Hex or standard
Numeric Data Entry. Positive contact tactile switches are included in a standard matrix arrangement.
An 8-bit data bus is required for pulsing and monitoring the keys.
Pull-Up resistors are included, together with a standard easy to connect IDCC connector for
interfacing. This board can be used with any microcontroller, with each pin separately polled or by
using a series of interrupt pins to monitor the keys.
The Keypad Mini Board will work with any of our controllers and is an easy to use solution for data
entry or simply as a series of switches.
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Features:
* 16 Keys Included for Hex and Numeric Input
* Keys Arranged in Standard Matrix Format
* Pull-Up Resistors Included
* Standard IDCC connector for easy connection
* Compact and Easy To Mount
* Ideal for use with all our Development and Control Boards
* Board Dimensions: 45 x 55 mm
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3.5 ZigBee
3.5.1 About ZigBee
Remote diagnosis ZigBee is a communications standard that provides a wireless autopilot
control short-range cost effective networking capability. It has been developed with the
emphasis on low-cost battery National Marine Electronics powered applications, such as,
building automation, Association standard data industrial and commercial controls, marine
wireless, over ZigBee personal healthcare and advanced tagging. ZigBee has been introduced
by the IEEE and the ZigBee Alliance to provide security the first general standard for these
applications.
3.5.2 Benefits of ZigBee
With a tenth of the processor memory requirements of Lighting Bluetooth and a fraction of
the MIPS needed for 802.11 Fire and safety systems networking devices, ZigBee is the best
solution for low data rate, short-range communications.
3.5.3 ZigBee also offers
y Low power consumption optimized formaintenance logging battery operation.
y License free operation in the 2.4GHz band.y Simple protocol definition can be implemented onlow-cost microcontrollers.
y Hundreds of devices per network.
y Network flexibility Star, Cluster Tree or Mesh configuration.
y Data rate up to 250kbps
y A well proven and researched standard that has been developed by some of the mostexperiencedcompanies in the world.
y Small size the developed solution will be less than 9mm x 9mm.
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3.5.4 Example Applications
1) Water Level SensingZigBee can be installed in remote locations whereconventional GSM modems would be
out of their network coverage area, such as inside water tanks. ZigBee transceivers can be
hermetically sealed with batteries and co- located with the sensors. Each transceiver transmits
periodically to another unit installed above ground. A GSM modem transmits the data back to base.
2) In-building Control
ZigBee- enabled switches and lights can reduce installation costs in new buildings by
eliminating themeeting current ZigBee protocols. Need to route light control through the walls, and
remove the need to call in a qualified electrician whenswitches need to be relocated. Thermostats
and air-conditioning controls can also be placed anywhere, free of any wiring constraints.
C-COORDINATORS R-ROUTERS E-END DEVICES
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SOFTWARE SECTION
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Chapter 4
SOFTWARE SECTION
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MAX 232
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Chapter 5
MAX 232
Old PC's used 25 pin connectors but only about 9 pins were actually used so today most
connectors are only 9-pin. Each of the 9 pins usually connects to a wire. Besides the two
wires used for transmitting and receiving data, another pin (wire) is signal ground. The
voltage on any wire is measured with respect to this ground. Thus the minimum number
of wires to use for 2-way transmission of data is 3. Except that it has been known to work
with no signal ground wire but with degraded performance and sometimes with errors.
There are still more wires which are for control purposes (signaling) only and not
for sending bytes. All of these signals could have been shared on a single wire, but
instead, there is a separate dedicated wire for every type of signal. Some (or all) of these
control wires are called "modem control lines". Modem control wires are either in the
asserted state (on) of +12 volts or in the negated state (off) of -12 volts. One of these wires
is to signal the computer to stop sending bytes out the serial port cable. Conversely,
another wire signals the device attached to the serial port to stop sending bytes to the
computer. If the attached device is a modem, other wires may tell the modem to hang up
the telephone line or tell the computer that a connection has been made or that the
telephone line is ringing (someone is attempting to call in). See section Pin out and
Signals for more details.
Figure MAX232
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Since the RS232 is not compatible with todays micro processors and microcontroller, we
need a line driver (voltage converter) to convert the RS232 signals to TTL voltage level that
will be acceptable to the 8052s TxD and RxD pins. One example of such a converter is
MAX232. The MAX232 converts from RS232 voltage levels to TTL voltage levels and vice
versa. One advantage of MAX232 chip is that it uses +5V power source, which is the same
as the source voltage for the 8052.
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APPLICATIONS
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Chapter 6
APPLICATIONS
6.1 Uses in hospitals
As in the hospitals we have to keep track of so many things like management of the
resources and the scheduling of everyone and everything. There are different types of labs
and the devices for diagnosis of the different kinds of disease. By using this technology we
can make proper utilization of resources, timely and proper management of people without
any hassles.
6.2 Uses in Banks
There is a huge mass of population which depends upon the banks for all their
monetary transactions. To keep a proper track of such huge mass of people and their
transactions this technology helps with certain degree of effectiveness.
6.2 Uses for Traffic Control
Its known to all of us that traffic are the good servants of the people and also the
major invention to help people but only if it is managed well otherwise we all know
Bangalores traffic how ridiculous and irritating it can be. So with the use of this technology
we can maintain the flow of traffic according to the needs of the people and also considering
the availability of roads.
6.3 Uses for advertisement
We can make use of this technology to display the different advertisement on display
panels to reach the larger number of people at a time and in the populated places like
shopping malls, road sides as well as at the theaters, discos, hotels, motels, restaurants etc
about their products and features
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6.4 Uses in Educational sector
Currently in India we are relying on the old style of displaying news by hanging bare
time consuming papers on the notice board which can be replaced by remote controlled
notice boards at the colleges and universities, also at the time of examination scheduling and
result publishing.
6.5 Information purpose
It would be wiser to make a use of this technology for information purpose like news
and its updates, real time reporting, live telecasting, inclusive of various information which
adds to the advanced and busy life on daily basis.
6.6 Stock Exchange
The stock exchange is the hot topic nowadays. There are millions of sales of shares every
hours and it is very necessary to maintain the real time services with the certain measures of
reliability because it deals with the money large number of the small or bigger investors.
With the help of this technology we can make it far easier and reliable.
6.7 Organization
Every organization has large number of employees who are assigned to accomplish the
various tasks and each and everything should be documented for the future reference
purpose. And also their schedules work, reports, leaves, presentation as well as distribution
of salary etc
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ENHANCEMENTS
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Chapter 7
ENHANCEMENTS
This technology can be used for broader application with the help of further enhancements
such as
1) It can be used to cover a wider range by the use of effective RF transmitter andreceiver.
2) Even we can increase the size of LCD so that it will be more practical and advancedwith its various features like wireless communication, remote controlling and
monitoring.
3) As the RF Transmitters and Receivers are temperature sensitive we can make aproper use of them to overcome its sensitivity.
4) Even if we see in wider application we can use it for the display of symbols, signs andfigures which can be easily understood and followed by normal non technical and
general people, mean while it also aids to the time utilization as time is the most
important factor in daily lives
5) On the other hand we have got the freedom to make it as two way communicationmedium. Which adds to one of the essential further enhancement, as communication
and information interchange has become one of the essential tools for the researches
and innovations?
6) Even it has a scope of sending and receiving e-mails on this device, which gives awider view and application with the help of mobile.
As we see from the above discussion it has the wide and extensive further
enhancements which add to the wider application, deployment of information technology,
which can change the face of present communication system providing better services in
the communication field to the people and organization.
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CONCLUSION
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Chapter 8
CONCLUSION
Form this article we conclude implementing Wireless Notice Board that:-
1) It eliminates the use of aprinter.
2) It isuser friendly i.e., any layman can operate it.
3) Messages can be sentanytime & correctedinstantaneously.
4) Messages lasts until the power in switched off.
5) Finally the cost of module comes in very low cost.
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BIBLIOGRAPHY
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Chapter 9
BIBLIOGRAPHY
1.DESIGN WITH PIC MICROCONTROLLERS - JOHN.B.PEATMAN
2. ANALOG ANDDIGITAL COMMUNICATION - SIMON HAYKINS
3. EMBEDDED SYSTEM DESIGN - FRANK VAHID & TONY GIVARGIS
WEBSITES
www.microchip.com
www.laipac.com
www.howstuffworks.com
www.u2.semiconductors.philips.com/i2c/facts/www.wikipedia.com
www.kartoo.com
www.google.com