MSP430G2553 internal temperature sensor

MSP430 Launchpad - Internal Temperature Sensor

Code:

#include <msp430g2553.h>

int temp = 0;

int main(void){

WDTCTL = WDTPW | WDTHOLD; //stop the watchdog timer


//Select 1.5 V, 64 clock cycles, enable ADC interrupt, Turn on the reference generator
ADC10CTL0 = SREF_1 + REFON + ADC10ON + ADC10SHT_3 + ADC10IE;

//Select input channel 10 and divide the clock frequency by 4
ADC10CTL1 = INCH_10 + ADC10DIV_3;

//Enable and Start conversion
ADC10CTL0 |= ENC + ADC10SC;

//Enter low power mode
__bis_SR_register(LPM0_bits + GIE);

//fetch the temperature value from ADC10MEM register
temp = ADC10MEM;

//convert it into degree celsius
temp = ((temp * 27069L - 18169625L)>>16);

return 0;

}

//ISR
#pragma vector = ADC10_VECTOR
__interrupt void adc_interrupt(void)

{
__bic_SR_register_on_exit(CPUOFF);
}

Explanation: https://youtu.be/51pAz11NklA