MSP430FR6989: ADC problem

How long did you run this before checking?

1) With ADC12MSC=0, you'll only get one conversion per ADC12SC trigger.

2) With ADC12MCTL7:ADC12EOS=0, it will cycle through all 32 channels before cycling back to ADC12MCTL0.

3) The ADC12MEMn registers are Undefined after Reset; I routinely see them with random numbers then.

I suspect you intended:

>  ADC12CTL0 = ADC12SHT0_3 | ADC12ON | ADC12MSC;  // CONSEQ=1 in a burst

and

>  ADC12MCTL7 |= ADC12INCH_7 | ADC12VRSEL_0 | ADC12EOS; // Final channel of the burst

Hello,

Thanks for the quick reply. I am not sure about how long the run time while debugging but I suppose that it was quite enough. I could not understand what do you mean by saying undefined ADC12MEMn register. Could you explain it more details? It would be better to refer it in code snippet.

I reduced sampling time rate and I set the channel 7 as the last channel of conversion. I also added that ADC12MSC register for getting more conversion. I still get the same result. 

You can check the updates below.

Regards.

#include <msp430.h>
#include <stdint.h>

volatile uint16_t adc_values[8]; 
volatile uint8_t adc_index = 0;  

void led_config();
void led_on();
void led_off();


void main(void) {
    WDTCTL = WDTPW + WDTHOLD;
    PM5CTL0 &= ~LOCKLPM5;


    ADC12CTL0 = ADC12SHT0_2 | ADC12MSC | ADC12ON;
    ADC12CTL1 = ADC12SHP | ADC12CONSEQ_1;   
    ADC12CTL2 = ADC12RES_2;
    ADC12CTL3 = ADC12CSTARTADD_0;
    ADC12MCTL0 |= ADC12INCH_0 | ADC12VRSEL_0; 
    ADC12MCTL1 |= ADC12INCH_1 | ADC12VRSEL_0; 
    ADC12MCTL2 |= ADC12INCH_2 | ADC12VRSEL_0; 
    ADC12MCTL3 |= ADC12INCH_3 | ADC12VRSEL_0; 
    ADC12MCTL4 |= ADC12INCH_4 | ADC12VRSEL_0; 
    ADC12MCTL5 |= ADC12INCH_5 | ADC12VRSEL_0;
    ADC12MCTL6 |= ADC12INCH_6 | ADC12VRSEL_0;
    ADC12MCTL7 |= ADC12INCH_7 | ADC12VRSEL_0 | ADC12EOS; 

    P9SEL0 |= 0xFF;
    P9SEL1 |= 0xFF;

    ADC12IER0 |= ADC12IE0 | ADC12IE1 | ADC12IE2 | ADC12IE3 | ADC12IE4 | ADC12IE5 | ADC12IE6 | ADC12IE7 ;
    ADC12CTL0 |= ADC12ENC;
    
    while(1) {

        ADC12CTL0 |= ADC12SC | ADC12ENC;   // ADC örnekleme ve dönüşümü başlat
        __delay_cycles(2000);
       __bis_SR_register(GIE);

    }
}




#pragma vector=ADC12_VECTOR
__interrupt void ADC_ISR(void) {
    switch(__even_in_range(ADC12IV, ADC12IV_ADC12RDYIFG))
    {
        case ADC12IV_ADC12IFG0:
            adc_values[0] = ADC12MEM0;
            break;
        case ADC12IV_ADC12IFG1:
            adc_values[1] = ADC12MEM1;
            break;
        case ADC12IV_ADC12IFG2:
            adc_values[2] = ADC12MEM2;
            break;
        case ADC12IV_ADC12IFG3:
            adc_values[3] = ADC12MEM3;
            break;
        case ADC12IV_ADC12IFG4:
            adc_values[4] = ADC12MEM4;
            break;
        case ADC12IV_ADC12IFG5:
            adc_values[5] = ADC12MEM5;
            break;
        case ADC12IV_ADC12IFG6:
            adc_values[6] = ADC12MEM6;
            break;
        case ADC12IV_ADC12IFG7:
            adc_values[7] = ADC12MEM7;
            break;

    }
}

Hello,

Thanks for the reply. I missed that port number thing. As you said, it connects to A8 to A15 and finally I was able to measure logical things. It works according to ADC12VRSEL_0 which is 3v3. However, I would like to measure 2V internal reference voltage. Here is my code. 

Could you please share your knowledge about using internal voltage referance? 

Thanks in advance.

#include <msp430.h>
#include <stdint.h>

volatile uint16_t adc_values[8]; // ADC değerlerini saklayacak dizi
volatile uint8_t adc_index = 0;  // ADC dizisi indeksi


void main(void) {

    WDTCTL = WDTPW + WDTHOLD;
    PM5CTL0 &= ~LOCKLPM5;

    P9SEL0 |= 0xFF;
    P9SEL1 |= 0xFF;


    ADC12CTL0 = ADC12SHT0_2 | ADC12MSC | ADC12ON; 
    ADC12CTL1 = ADC12SHP | ADC12CONSEQ_1;                     
    ADC12CTL2 = ADC12RES_2; 
    ADC12CTL3 = ADC12CSTARTADD_0;
    ADC12MCTL0 |= ADC12INCH_8 ; // A1 ADC input select; Vref=AVCC
    ADC12MCTL1 |= ADC12INCH_9 ; // A1 ADC input select; Vref=AVCC
    ADC12MCTL2 |= ADC12INCH_10 ; // A1 ADC input select; Vref=AVCC
    ADC12MCTL3 |= ADC12INCH_11 ; // A1 ADC input select; Vref=AVCC
    ADC12MCTL4 |= ADC12INCH_12 ; // A1 ADC input select; Vref=AVCC
    ADC12MCTL5 |= ADC12INCH_13 ;// A1 ADC input select; Vref=AVCC
    ADC12MCTL6 |= ADC12INCH_14 ; // A1 ADC input select; Vref=AVCC
    ADC12MCTL7 |= ADC12INCH_15 | ADC12EOS; // A1 ADC input select; Vref=AVCC


    while(REFCTL0 &REFGENBUSY);
    REFCTL0 |= REFVSEL_1 | REFON;
    while(!(REFCTL0 &REFGENRDY));

    ADC12IER0 |= ADC12IE7;
    
    ADC12CTL0 |= ADC12ENC;


    while(1) {
        ADC12CTL0 |= ADC12SC | ADC12ENC;   // ADC örnekleme ve dönüşümü başlat
       __bis_SR_register(LPM0_bits | GIE);

    }
}




#pragma vector=ADC12_VECTOR
__interrupt void ADC_ISR(void) {
    switch(__even_in_range(ADC12IV, ADC12IV_ADC12RDYIFG))
    {

        case ADC12IV_ADC12IFG7:
            adc_values[0] = ADC12MEM0;
            adc_values[1] = ADC12MEM1;
            adc_values[2] = ADC12MEM2;
            adc_values[3] = ADC12MEM3;
            adc_values[4] = ADC12MEM4;
            adc_values[5] = ADC12MEM5;
            adc_values[6] = ADC12MEM6;
            adc_values[7] = ADC12MEM7;
            __bic_SR_register_on_exit(LPM0_bits);
            break;

    }

}

Hi,

I have added the voltage referans selection and it worked. Here is the last version of code. 

Thanks for helping.

#include <msp430.h>
#include <stdint.h>

volatile uint16_t adc_values[8]; // ADC değerlerini saklayacak dizi
volatile uint8_t adc_index = 0;  // ADC dizisi indeksi


void main(void) {

    WDTCTL = WDTPW + WDTHOLD;
    PM5CTL0 &= ~LOCKLPM5;

    P9SEL0 |= 0xFF;
    P9SEL1 |= 0xFF;


    ADC12CTL0 = ADC12SHT0_2 | ADC12MSC | ADC12ON; 
    ADC12CTL1 = ADC12SHP | ADC12CONSEQ_1;                     
    ADC12CTL2 = ADC12RES_2; 
    ADC12CTL3 = ADC12CSTARTADD_0;
    ADC12MCTL0 |= ADC12INCH_8 | ADC12VRSEL_1 ; 
    ADC12MCTL1 |= ADC12INCH_9 | ADC12VRSEL_1; 
    ADC12MCTL2 |= ADC12INCH_10 | ADC12VRSEL_1 ; 
    ADC12MCTL3 |= ADC12INCH_11 | ADC12VRSEL_1 ;
    ADC12MCTL4 |= ADC12INCH_12 | ADC12VRSEL_1 ; 
    ADC12MCTL5 |= ADC12INCH_13 | ADC12VRSEL_1 ;
    ADC12MCTL6 |= ADC12INCH_14 | ADC12VRSEL_1 ;
    ADC12MCTL7 |= ADC12INCH_15 | ADC12VRSEL_1 | ADC12EOS; 


    while(REFCTL0 &REFGENBUSY);
    REFCTL0 |= REFVSEL_1 | REFON;
    while(!(REFCTL0 &REFGENRDY));

    ADC12IER0 |= ADC12IE7;
    
    ADC12CTL0 |= ADC12ENC;


    while(1) {
        ADC12CTL0 |= ADC12SC | ADC12ENC;   // ADC örnekleme ve dönüşümü başlat
       __bis_SR_register(LPM0_bits | GIE);

    }
}




#pragma vector=ADC12_VECTOR
__interrupt void ADC_ISR(void) {
    switch(__even_in_range(ADC12IV, ADC12IV_ADC12RDYIFG))
    {

        case ADC12IV_ADC12IFG7:
            adc_values[0] = ADC12MEM0;
            adc_values[1] = ADC12MEM1;
            adc_values[2] = ADC12MEM2;
            adc_values[3] = ADC12MEM3;
            adc_values[4] = ADC12MEM4;
            adc_values[5] = ADC12MEM5;
            adc_values[6] = ADC12MEM6;
            adc_values[7] = ADC12MEM7;
            __bic_SR_register_on_exit(LPM0_bits);
            break;

    }

}