CCS/LDC1612EVM: UART Communication and ADC

Tool/software: Code Composer Studio

Hello guys,

We are developing a system based on the LDC1612EVM board, however we have a Temperatur Sensor on PIN A7.

My Code is based on the sample Code for the LDC1612EVM Board. I have a UART Communication with the Host PC which I have modified to communicate directly with 3rd Party Com Tools.

My Problem is reading the ADC values. Below my Code for reading the ADC.

initTemp will be executed in main, but not in the Loop.

When starting a Stream to get LDC Values the TempLoop get executed, LDC values are pulled from the LDC and then getTemp is executed.

Doing it this way i get unstable values from the ADC. In Temperature Scale a difference from 9°C. I am using the TMP236 as Tempsensor.

When I using the interrupt from the ADC my UART Communication doesn't work.

What can I do to improve the accuracy of my Temp sensor?

Best regards

volatile temp Temperatur;
volatile uint8_t trigger = 0;

#if defined(__TI_COMPILER_VERSION__) || defined(__IAR_SYSTEMS_ICC__)
#pragma vector=ADC12_VECTOR
__interrupt void ADC12ISR (void)
#elif defined(__GNUC__)
void __attribute__ ((interrupt(ADC12_VECTOR))) ADC12ISR (void)
#else
#error Compiler not supported!
#endif
{
    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  8: break;                           // Vector  8:  ADC12IFG1
  case 10: break;                           // Vector 10:  ADC12IFG2
  case 12:                                  // Vector 12:  ADC12IFG3
    __bic_SR_register_on_exit(LPM4_bits);   // Exit active CPU, SET BREAKPOINT HERE
    break;
  case 14: break;                           // Vector 14:  ADC12IFG4
  case 16: break;                           // Vector 16:  ADC12IFG5
  case 18: break;                           // Vector 18:  ADC12IFG6
  case 20: break;                           // Vector 20:  ADC12IFG7
  case 22: break;                           // Vector 22:  ADC12IFG8
  case 24: break;                           // Vector 24:  ADC12IFG9
  case 26: break;                           // Vector 26:  ADC12IFG10
  case 28: break;                           // Vector 28:  ADC12IFG11
  case 30: break;                           // Vector 30:  ADC12IFG12
  case 32: break;                           // Vector 32:  ADC12IFG13
  case 34: break;                           // Vector 34:  ADC12IFG14
  default: break;
  }
}

void initTemp(){
    P6SEL = TEMP_PIN;          // Enable A/D channel A7
    REFCTL0 &= ~REFMSTR;
    ADC12CTL0 = ADC12ON+ADC12SHT0_8+ADC12REFON;  // Turn on ADC12, extend sampling time
    ADC12CTL1 = ADC12SHP;                       // Use sampling timer
    ADC12IE = 0x08;
    __delay_cycles(100);
    ADC12CTL0 |= ADC12ENC;
}

void TempLoop(){
    ADC12CTL0 |= ADC12SC;
    //__bis_SR_register(LPM4_bits + GIE);     // Enter LPM4, Enable interrupts
    //__no_operation();

}

temp getTemp() {
    Temperatur.raw = ADC12MEM0;
    float test = (((float)Temperatur.raw * (1.5f/4096)) - 0.4f)/0.019f;
    Temperatur.num1 = test;
    Temperatur.num2 = ((test - Temperatur.num1) >= 0.5f) ? 5 : 0;
    return Temperatur;
}