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3 axis accelerometer Interfacing with MSP430

3 axis accelerometer Interfacing with MSP430

// create file named called 3axisaccelerometer.c and paste below given program

* Project name:

3-AXIS ACCELEROMETER

* Copyright

* Test configuration:

MCU: MSP430G2553

Dev.Board: TI LAUNCHPAD

Oscillator: 16 MHz

Software: CCS STUDIO V.5

#include "msp430g2553.h"

#include "lcd.h"

#define LED1 BIT0

int itoa(int n, char* out);

void reverse(char* str, int length);

//int temp;

char buffer[33];

char buffer2[33];

char buffer3[33];

int itoa(int n, char* out)

{

// if negative, need 1 char for the sign

int sign = n < 0? 1: 0;

int i = 0;

if (n == 0) {

out[i++] = '0';

} else if (n < 0) {

out[i++] = '-';

n = -n;

}

while (n > 0) {

out[i++] = '0' + n % 10;

n /= 10;

}

out[i] = '\0';

reverse(out + sign, i - sign);

return 0;

}

void reverse(char* str, int length){

int i = 0, j = length-1;

char tmp;

while (i < j) {

tmp = str[i];

str[i] = str[j];

str[j] = tmp;

i++; j--;

}

int main(void)

{

WDTCTL = WDTPW + WDTHOLD; //Stop WDT

BCSCTL1 = CALBC1_8MHZ; //Set DCO to 8Mhz

DCOCTL = CALDCO_8MHZ; //Set DCO to 8Mhz

P1DIR &= ~0xF0; // set pin direction for led

P1DIR |= BIT0;

P2DIR&=~BIT3;

InitializeLcm(); //INITIALIZE LCD

__delay_cycles(1000000);

__enable_interrupt();

int value;

char *text;

while(1)

{

ADC10CTL1 = INCH_3 + ADC10DIV_3 ;

ADC10CTL0 = SREF_0 + ADC10SHT_3 + ADC10ON + ADC10IE;

ADC10AE0 |= BIT3;

ADC10CTL0 |= ENC + ADC10SC; // Sampling and conversion start

__bis_SR_register(CPUOFF + GIE); // LPM0 with interrupts enabled

value = ADC10MEM;

itoa(value,buffer);

ClearLcmScreen();

PrintStr("X="); //DISPLAY ON LCD

PrintStr(buffer);

__delay_cycles(100000); // Wait for ADC Ref to settle

ADC10CTL1 = INCH_4 + ADC10DIV_3 ;

ADC10CTL0 = SREF_0 + ADC10SHT_3 + ADC10ON + ADC10IE;

ADC10AE0 |= BIT4;

ADC10CTL0 |= ENC + ADC10SC; // Sampling and conversion start

__bis_SR_register(CPUOFF + GIE); // LPM0 with interrupts enabled

value = ADC10MEM;

itoa(value,buffer2);

ClearLcmScreen();

PrintStr("Y="); //DISPLAY ON LCD

PrintStr(buffer2);

__delay_cycles(100000);

ADC10CTL1 = INCH_5 + ADC10DIV_3 ;

ADC10CTL0 = SREF_0 + ADC10SHT_3 + ADC10ON + ADC10IE;

ADC10AE0 |= BIT5;

ADC10CTL0 |= ENC + ADC10SC; // Sampling and conversion start

__bis_SR_register(CPUOFF + GIE); // LPM0 with interrupts enabled

value = ADC10MEM;

itoa(value,buffer3);

ClearLcmScreen();

PrintStr("Z="); //DISPLAY ON LCD

PrintStr(buffer3);

__delay_cycles(100000);

}

// ADC10 interrupt service routine

#pragma vector=ADC10_VECTOR

__interrupt void ADC10_ISR (void)

{

__bic_SR_register_on_exit(CPUOFF); // Return to active mode

P1OUT ^= LED1;

}

// end of 3axisaccelerometer.c file

//…………………………………………………………………………………………..

// create file named called lcd.c and paste below given program

#include "msp430g2553.h"

#include "lcd.h"

#define LCM_DIR P2DIR

#define LCM_OUT P2OUT

// Define symbolic LCM - MCU pin mappings

// We've set DATA PIN TO 4,5,6,7 for easy translation

#define LCM_PIN_RS BIT0 // P2.0

#define LCM_PIN_EN BIT1 // P2.1

#define LCM_PIN_D7 BIT3 // P2.3

#define LCM_PIN_D6 BIT2 // P2.2

#define LCM_PIN_D5 BIT5 // P2.5

#define LCM_PIN_D4 BIT4 // P2.4

#define FALSE 0

#define TRUE 1

// Routine Desc:

// This is the function that must be called

// whenever the LCM needs to be told to

// scan it's data bus.

// Parameters:

// void.

// Return

// void.

void PulseLcm()

{

// pull EN bit low

LCM_OUT &= ~LCM_PIN_EN;

__delay_cycles(200);

// pull EN bit high

LCM_OUT |= LCM_PIN_EN;

__delay_cycles(200);

// pull EN bit low again

LCM_OUT &= (~LCM_PIN_EN);

__delay_cycles(200);

}

// Routine Desc:

// Send a byte on the data bus in the 4 bit mode

// This requires sending the data in two chunks.

// The high nibble first and then the low nible

// Parameters:

// ByteToSend - the single byte to send

// IsData - set to TRUE if the byte is character data

// FALSE if its a command

// Return

// void.

void SendByte(char ByteToSend, int IsData)

{

// clear out all pins

LCM_OUT &= (~LCM_PIN_MASK);

// set High Nibble (HN) -

// usefulness of the identity mapping

// apparent here. We can set the

// DB7 - DB4 just by setting P1.7 - P1.4

// using a simple assignment

LCM_OUT |= (ByteToSend & 0xF0);

if (IsData == TRUE)

{

LCM_OUT |= LCM_PIN_RS;

}

else

{

LCM_OUT &= ~LCM_PIN_RS;

}

// we've set up the input voltages to the LCM.

// Now tell it to read them.

PulseLcm();

// set Low Nibble (LN) -

// usefulness of the identity mapping

// apparent here. We can set the

// DB7 - DB4 just by setting P1.7 - P1.4

// using a simple assignment

LCM_OUT &= (~LCM_PIN_MASK);

LCM_OUT |= ((ByteToSend & 0x0F) << 4);

if (IsData == TRUE)

{

LCM_OUT |= LCM_PIN_RS;

}

else

{

LCM_OUT &= ~LCM_PIN_RS;

}

// we've set up the input voltages to the LCM.

// Now tell it to read them.

PulseLcm();

}

// Routine Desc:

// Set the position of the cursor on the screen

// Parameters:

// Row - zero based row number

// Col - zero based col number

// Return

// void.

void LcmSetCursorPosition(char Row, char Col)

{

char address;

// construct address from (Row, Col) pair

if (Row == 0)

{

address = 0;

}

else

{

address = 0x40;

}

address |= Col;

SendByte(0x80 | address, FALSE);

}

// Routine Desc:

// Clear the screen data and return the

// cursor to home position

// Parameters:

// void.

// Return

// void.

void ClearLcmScreen()

{

// Clear display, return home

SendByte(0x01, FALSE);

SendByte(0x02, FALSE);

}

// Routine Desc:

// Initialize the LCM after power-up.

// Note: This routine must not be called twice on the

// LCM. This is not so uncommon when the power

// for the MCU and LCM are separate.

// Parameters:

// void.

// Return

// void.

void InitializeLcm(void)

{

// set the MSP pin configurations

// and bring them to low

LCM_DIR |= LCM_PIN_MASK;

LCM_OUT &= ~(LCM_PIN_MASK);

// wait for the LCM to warm up and reach

// active regions. Remember MSPs can power

// up much faster than the LCM.

__delay_cycles(100000);

// initialize the LCM module

// 1. Set 4-bit input

LCM_OUT &= ~LCM_PIN_RS;

LCM_OUT &= ~LCM_PIN_EN;

LCM_OUT = 0x20;

PulseLcm();

// set 4-bit input - second time.

// (as reqd by the spec.)

SendByte(0x28, FALSE);

// 2. Display on, cursor on, blink cursor

SendByte(0x0E, FALSE);

// 3. Cursor move auto-increment

SendByte(0x01, FALSE);

}

// Routine Desc

// Print a string of characters to the screen

// Parameters:

// Text - null terminated string of chars

// Returns

// void.

void PrintStr(char *Text)

{

char *c;

c = Text;

while ((c != 0) && (*c != 0))

{

SendByte(*c, TRUE);

c++;

}

// Routine Desc

// main entry point to the sketch

// Parameters

// void.

// Returns

// void.

// end of lcd.c file

//…………………………………………………………………………………………..

// create file named called lcd.h and paste below given program

void PulseLcm();

void SendByte(char ByteToSend, int IsData);

void LcmSetCursorPosition(char Row, char Col);

void ClearLcmScreen();

void InitializeLcm(void);

void PrintStr(char *text);

// end of lcd.h file

//…………………………………………………………………………………………..