dEVELOP Umavrk WIRELESS sensing system with · PDF fileApplication Note [DEVELOP UMAVRK WIRELESS SENSING SYSTEM WITH CCS] ChaiYong Lim | ECE480 Spring 2012 3 Introduction The UR-CC430F5137-MVK

Application Note [DEVELOP UMAVRK WIRELESS SENSING SYSTEM WITH CCS]

ChaiYong Lim | ECE480 Spring 2012 1

Developing a uMAVRK Wireless Sensing

System with CCS

ChaiYong Lim

March 30th

, 2012

ECE480 Design Team 2

Summary

This application note is intended to guide the reader through the process of using the code

composer studio (CCS) to develop a one to one wireless sensing system on UR-CC430F5137-

MVK module. It includes detail information about how the module functions and how to develop

the wireless sensing system based on TI example code. Figures and Schematics are also included

in this application notes.

Keywords: MAVRK, wireless sensing, MSP430, RF communication, micro-controller, CCS



Table of Contents

Introduction ................................................................................................................................................... 3

Objective ....................................................................................................................................................... 3

Getting Started .............................................................................................................................................. 4

Create a CCS Project .................................................................................................................................... 4

Modify the RF example code ........................................................................................................................ 6

Program the UR-CC430F5137-MVK modules ............................................................................................ 7

Include the UART function ......................................................................................................................... 8

Include the ADC function ............................................................................................................................. 9

Include the WDT function .......................................................................................................................... 10

Final Integration ......................................................................................................................................... 10

Complete Code............................................................................................................................................ 11



Introduction

The UR-CC430F5137-MVK contains a 16-bit ultra low power CC430F5137 MCU with a

high performance sub 1 GHZ RF transceiver core. This makes it an excellent choice in wireless

monitoring sensor system, self designed sensor board may be attached on this device. It is

designed to be used in end-product and run independently of the Modular and Versatile

Reference Kit (MAVRK) motherboard but it may be also connected to the motherboard via a

RF-UDEBUG-MVK MAVRK module.

Objective

It is assumed the reader has a basic knowledge of micro-controller and C programming

language but has no experience developing application on UR-CC430F5137-MVK module. By

the end of the document the reader should have an understanding of how to:

Program the UR-CC430F5137-MVK module

Implement RF communication

Implement ADC conversion

Implement UART communication

Implement Watch-Dog Timer

Display acquisitioned data on HyperTerminal



Getting Started

Hardware Requirements:

1. Two UR-CC430F5137-MVK modules.

2. One RF-UDEBUG-MVK module.

3. Power supply and battery packs.

4. DMM multi meter.

5. MSP-FET430UIF development tool.

6. EZ430-RF2500 development tool.

Software Requirement:

1. Code Composer Studio v5

2. HyperTerminal

Download the Code Composer Studio v5 from the TI Wiki page and install it on your computer,

you may need a MyTI account to download it. To save your hard drive space, choose custom

install and check only the MSP430. Download the CC430 RF Example codes from the TI

CC430F5137 web page under the application notes section; this is the code we are trying to build

on top of it. Download the CC430F513x C example codes from the TI CC430F5137 web page

under the software and development tools section; these example codes are very useful for

learning how to use different CC430F5137 functionality.

Create a CCS Project

Open the Code Composer Studio v5, set your own workplace path and choose evaluate for

license setup. By choosing evaluate option can use the full features of CCS for 90 days which is

more than enough for your design project. Click on the Project tab and click New CCS Project,

enter your project name, select CC430x5xx Family from your Variant tab and select

CC430F5137 next to it, shown as below figure.

http://processors.wiki.ti.com/index.php/Category:Code_Composer_Studio_v5

http://www.ti.com/product/cc430f5137




Open the folder CC430x513x RF examples that you download from TI CC430F5137 web page

and open the sub folder RF_Examples_CCS, open the sub folder Fixed_LT_FIFO and copy the

file RF_Toggle_LED_Demo.h and all the files from HAL folder into your CCS Project folder.

Next, copy the entire content from RF_Toggle_LED_Demo.c to main.c under your CCS Project

folder. The resulting window should be the same as the figure below.




Modify the RF example code

To make this example code work on the UR-CC430F5137-MVK module, some modifications

need to be done on the example code. First, download the UR-CC430F5137-MVK schematic

from TI wiki page. The below figure is the partial schematic where extracted from the full

schematic, note that the green LED is connected to the port PJ.0 and the yellow LED is

connected to the port PJ.1. Also, there are two switch buttons on the UR-CC430F5137-MVK

module where one served as a reset button and another one is served as an input button which is

connected to the port P2.7. However, the example code assumed the input button is connected to

port P1.7 and the two LED’s are connected to P3.6 and P1.0. Therefore, we need to change all

the corresponding I/O port to the correct Port number at line 73, line 75, line 82, the entire

InitButtonLeds sub function, line 207 and line 212. We define the green LED as transmit signal

and yellow LED as receive signal.

http://processors.wiki.ti.com/images/f/f2/UR-CC430F5137-MVK_SCH.pdf



Program the UR-CC430F5137 modules

After the modifications are done, attach the UR-CC430F5137-MVK on the RF-UDEBUG-MVK

module, plug in the JTAG connector and click the debug button (green bug) on the CCS. The

compilation should build successfully and program the UR-CC430F5137-MVK module with no

error. Similarly, program another UR-CC430F5137-MVK module by the same procedures. After

the both UR-CC430F5137-MVK modules are programmed successfully, try connected both

modules with battery pack and press the input button of either one module. The green LED on

the module which the input button is pressed should blink and the yellow LED on the other

module should blink next, this implies that the packet is successfully sent and received

wirelessly.



Include the UART function

Define void InitUART(void) in RF_Toggle_LED_Demo.h, look into the CC430x513x code

examples folder, there are 4 different UART example codes, to understand what is the different,

look at chapter 19 of the CC430F5137 user guide is recommended, this application note will use

the third mode of UART, open the file cc430x513x_uscia0_uart_03.c, note that this example

map the UART Tx/Rx port to P2.7 and P2.6. We need to use the default UART port P1.6 and

P1.5, in the InitUART sub function, set P1.6 as output and P1.5 as input by set the bit 6 of

P1DIR to 1 and set the bit 5 of P1DIR to 0. Copy the rest of the UART register setting code to

your InitUART sub function. The result should look similar as the figure shown below.

To output a character through UART, you need to check whether the Tx Buffer is ready or not, if

it is not ready, UCA0IFG&UCTXIFG will give a result 1. You should wait until the flag is clear

to store the character you want to send into the buffer UCA0TXBUF. Connect the UR-

CC430F5137-MVK receiver to the ez430 connector and plug it into your PC USB port. You may

need to install the ez430 driver. Open your HyperTerminal and set the baud rate to 9600, 8 bit,

none parity check and no flow control. The HyperTerminal should be ready to receive data from

the receiver.

http://www.ti.com/lit/ug/slau259b/slau259b.pdf



Include the ADC function

Define void InitADC(void) in RF_Toggle_LED_Demo.h, look into the CC430x513x code

examples folder, there are 10 different UART example codes, to understand what is the different,

look at chapter 17 of the CC430F5137 user guide is recommended, this application note will

adapt from the cc430x513x_adc12_09.c example code and build on top of it, open the file

cc430x513x_adc12_09.c, note that this example shows how to perform A/D conversions on a

sequence of channels. A single sequence of conversions is performed - one conversion each on

channels A0, A1, A2, and A3. Each conversion uses AVcc and AVss for the references. The

conversion results are stored in ADC12MEM0, ADC12MEM1, ADC12MEM2, and

ADC12MEM3 respectively and are moved to 'results[]' upon completion of the sequence. In this

application note, we use channel A2 and A4. Similarly, copy the initialize setting code into the

sub function InitADC(void) and the interrupt service routine as well. The result should look

similar as the figure shown below.




Include the WDT function

Although you have already included the ADC function, you need to include a timer for sampling

your analog input. To create a timer, watch dog timer is used in this application note, define void

InitWDT(void) in your header file exactly as previous section. Copy the following code into

your sub function as the figure shown below, this setting set the watch dog timer interval to be

1000ms. Also, copy the watch dog timer service routine



Final Integration

Now you have all the components you need for this application, there are several ways to

integrate all the components, depends on your designed flow chart. The following code is the

complete code we use in our application. Details explanations for the register setting of

CC430F5137 are out of the scoop in this application note, further reading in the CC430F5137

user guide is recommended.

The Complete Code

#include "RF_Toggle_LED_Demo.h"

#include "stdio.h"

volatile int results[4]; // Needs to be global in this example

// Otherwise, the compiler removes it

// because it is not used for anything.

#define PACKET_LEN (5) // PACKET_LEN <= 61

#define RSSI_IDX (PACKET_LEN) // Index of appended RSSI

#define CRC_LQI_IDX (PACKET_LEN+1) // Index of appended LQI, checksum

#define CRC_OK (BIT7) // CRC_OK bit

#define PATABLE_VAL (0x51) // 0 dBm output

extern RF_SETTINGS rfSettings;

unsigned char packetReceived;

unsigned char packetTransmit;

unsigned char RxBuffer[PACKET_LEN+2];

unsigned char RxBufferLength = 0;

unsigned char TxBuffer[PACKET_LEN];

unsigned char buttonPressed = 0;

unsigned int i = 0;

unsigned char transmitting = 0;

unsigned char receiving = 0;

void main( void )

{

// Stop watchdog timer to prevent time out reset

WDTCTL = WDTPW + WDTHOLD;

// Increase PMMCOREV level to 2 for proper radio operation




SetVCore(2);

ResetRadioCore();

InitRadio();

InitButtonLeds();

InitUART();

InitADC();

ReceiveOn();

receiving = 1;

while (1)

{

__bis_SR_register( LPM3_bits + GIE );

__no_operation();

if (buttonPressed) // Process a button press->transmit

{

buttonPressed = 0;

P2IFG = 0;

ReceiveOff();

receiving = 0;

transmitting = 1;

InitWDT();

}

else if(!transmitting)

{

ReceiveOn();

receiving = 1;

}

}

}

void InitWDT(void)

{

WDTCTL = WDT_ADLY_1000; // WDT 250ms, ACLK, interval timer

SFRIE1 |= WDTIE; // Enable WDT interrupt

}

void InitButtonLeds(void)

{

// Set up the button as interruptible

P2DIR &= ~BIT7;

P2REN |= BIT7;

P2IES &= BIT7;

P2IFG = 0;

P2OUT |= BIT7;

P2IE |= BIT7;



// Initialize Port J

PJOUT = 0x00;

PJDIR = 0xFF;

// Set up LEDs

PJOUT &= ~BIT0;

PJOUT &= ~BIT1;

}

void InitUART (void)

{

P1DIR |= BIT6; // Set P1.6 as TX output

P1DIR &= ~BIT5; // Set P1.5 as RX input

P1SEL |= BIT6 + BIT5; // Select P1.5 & P1.6 to UART function

UCA0CTL1 |= UCSWRST; // **Put state machine in reset**

UCA0CTL1 |= UCSSEL_1; // CLK = ACLK

UCA0BR0 = 0x03; // 32kHz/9600=3.41 (see User's Guide)

UCA0BR1 = 0x00; //

UCA0MCTL = UCBRS_3+UCBRF_0; // Modulation UCBRSx=3, UCBRFx=0

UCA0CTL1 &= ~UCSWRST; // **Initialize USCI state machine**

}

void InitADC (void)

{

P2SEL = BIT2+BIT4; // Enable A/D channel inputs

ADC12CTL0 = ADC12ON+ADC12MSC+ADC12SHT0_2; // Turn on ADC12, set sampling time

ADC12CTL1 = ADC12SHP+ADC12CONSEQ_1; // Use sampling timer, single sequence

ADC12MCTL2 = ADC12INCH_2; // ref+=Vacc+, channel = A2

ADC12MCTL4 = ADC12INCH_4+ADC12EOS; // ref+=Vacc+, channel = A4, end seq.

ADC12IE = ADC12IE4; // Enable ADC12IFG.3

ADC12CTL0 |= ADC12ENC; // Enable conversions

}

void output(unsigned char ch)

{

while (!(UCA0IFG&UCTXIFG)); // USCI_A0 TX buffer ready?

UCA0TXBUF = ch; // Output ch

}

/* sufficient for decimal rep of 16-bit number + newline + '\0' termination */

void print()

{

RxBuffer[PACKET_LEN] = '\n';

RxBuffer[PACKET_LEN+1] = '\r';

for (i = 0;i < sizeof(RxBuffer);i++)

{



output(RxBuffer[i]);

}

}

void InitRadio(void)

{

// Set the High-Power Mode Request Enable bit so LPM3 can be entered

// with active radio enabled

PMMCTL0_H = 0xA5;

PMMCTL0_L |= PMMHPMRE_L;

PMMCTL0_H = 0x00;

WriteRfSettings(&rfSettings);

WriteSinglePATable(PATABLE_VAL);

}

void Transmit(unsigned char *buffer, unsigned char length)

{

RF1AIES |= BIT9;

RF1AIFG &= ~BIT9; // Clear pending interrupts

RF1AIE |= BIT9; // Enable TX end-of-packet interrupt

WriteBurstReg(RF_TXFIFOWR, buffer, length);

Strobe( RF_STX ); // Strobe STX

}

void ReceiveOn(void)

{

RF1AIES |= BIT9; // Falling edge of RFIFG9

RF1AIFG &= ~BIT9; // Clear a pending interrupt

RF1AIE |= BIT9; // Enable the interrupt

// Radio is in IDLE following a TX, so strobe SRX to enter Receive Mode

Strobe( RF_SRX );

}

void ReceiveOff(void)

{

RF1AIE &= ~BIT9; // Disable RX interrupts

RF1AIFG &= ~BIT9; // Clear pending IFG

// It is possible that ReceiveOff is called while radio is receiving a packet.

// Therefore, it is necessary to flush the RX FIFO after issuing IDLE strobe

// such that the RXFIFO is empty prior to receiving a packet.

Strobe( RF_SIDLE );

Strobe( RF_SFRX );



}

#pragma vector=PORT2_VECTOR

__interrupt void PORT2_ISR(void)

{

switch(__even_in_range(P2IV, 16))

{

case 0: break;

case 2: break; // P1.0 IFG







case 16: // P1.7 IFG

P2IE = 0; // Debounce by disabling buttons

buttonPressed = 1;

__bic_SR_register_on_exit(LPM3_bits); // Exit active

break;

}

}

// Watchdog Timer interrupt service routine

#pragma vector = WDT_VECTOR

__interrupt void WDT_ISR(void)

{

PJOUT |= BIT0; // Pulse LED during Transmit

ADC12CTL0 |= ADC12SC;

}

#pragma vector=ADC12_VECTOR

__interrupt void ADC12ISR (void)

{

switch(__even_in_range(ADC12IV,34))

{

case 0: break; // Vector 0: No interrupt

case 2: break; // Vector 2: ADC overflow

case 4: break; // Vector 4: ADC timing overflow

case 6: break; // Vector 6: ADC12IFG0






case 14:

results[0] = ADC12MEM2; // Move results, IFG is cleared

results[1] = ADC12MEM4; // Move results, IFG is cleared

sprintf((char*)TxBuffer,"A%d",results[0]);

Transmit( (unsigned char*)TxBuffer, sizeof TxBuffer);

__delay_cycles(10000);

sprintf((char*)TxBuffer,"B%d",results[1]);

Transmit( (unsigned char*)TxBuffer, sizeof TxBuffer);

break; // Vector 14: ADC12IFG4











default: break;

}

}

#pragma vector=CC1101_VECTOR

__interrupt void CC1101_ISR(void)

{

switch(__even_in_range(RF1AIV,32)) // Prioritizing Radio Core Interrupt

{

case 0: break; // No RF core interrupt pending

case 2: break; // RFIFG0









case 20: // RFIFG9

if(receiving) // RX end of packet

{

// Read the length byte from the FIFO

RxBufferLength = ReadSingleReg( RXBYTES );



ReadBurstReg(RF_RXFIFORD, RxBuffer, RxBufferLength);

// Stop here to see contents of RxBuffer

__no_operation();

// Check the CRC results

if(RxBuffer[CRC_LQI_IDX] & CRC_OK)

{

PJOUT |= BIT1; // Turn on LED1

print();

PJOUT &= ~BIT1; // Turn off LED1

}

ReceiveOn();

}

else if(transmitting) // TX end of packet

{

RF1AIE &= ~BIT9; // Disable TX end-of-packet interrupt

PJOUT &= ~BIT0; // Turn off LED after Transmit

}

else while(1); // trap

break;







}

}

Documents

dEVELOP Umavrk WIRELESS sensing system with · PDF fileApplication Note [DEVELOP UMAVRK WIRELESS SENSING SYSTEM WITH CCS] ChaiYong Lim | ECE480 Spring 2012 3 Introduction The UR-CC430F5137-MVK