CCS/LAUNCHXL-F28379D: Simultaneous Sampling in F28379D

Hi Whitney,

I did all changes, but for input signal  in the second channel (ADC B2) does not accept data and does not work.

main.c  :

uint16_t RFFTin1Buff[2*RFFT_SIZE];
uint16_t RFFTin2Buff[2*RFFT_SIZE];//<-----------------------------------new


__interrupt void adcaIsr()
{
    RFFTin1Buff[sampleIndex++] = AdcaResultRegs.ADCRESULT0;
    RFFTin2Buff[sampleIndex++] = AdcbResultRegs.ADCRESULT0;//<----------------------------new
    if(sampleIndex == (RFFT_SIZE - 1) ){
        sampleIndex = 0;
        flagInputReady = 1;
    }

    AdcaRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; //clear INT1 flag
    AdcbRegs.ADCINTFLGCLR.bit.ADCINT1 = 1; //clear INT1 flag//<----------------------------new
    PieCtrlRegs.PIEACK.all = PIEACK_GROUP1;
}

examples_setup.c  :

void FPU_initADCA(void)
{
    EALLOW;
    //write configurations
    AdcaRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4
    AdcbRegs.ADCCTL2.bit.PRESCALE = 6; //set ADCCLK divider to /4  //<-----------------------------------new
    AdcSetMode(ADC_ADCA, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);
    AdcSetMode(ADC_ADCB, ADC_RESOLUTION_12BIT, ADC_SIGNALMODE_SINGLE);//<-----------------------------------new
    //Set pulse positions to early
    AdcaRegs.ADCCTL1.bit.INTPULSEPOS = 0;
    AdcbRegs.ADCCTL1.bit.INTPULSEPOS = 0;//<-----------------------------------new
    //power up the ADC
    AdcaRegs.ADCCTL1.bit.ADCPWDNZ = 1;
    AdcbRegs.ADCCTL1.bit.ADCPWDNZ = 1;//<-----------------------------------new
    //delay for 1ms to allow ADC time to power up
    DELAY_US(1000);

    //Select the channels to convert and end of conversion flag ADCA
    AdcaRegs.ADCSOC0CTL.bit.CHSEL     = 0;  //SOC0 will convert pin A0
    AdcaRegs.ADCSOC0CTL.bit.ACQPS     = 14; //sample window is 15 SYSCLK cycles
    AdcaRegs.ADCSOC0CTL.bit.TRIGSEL   = 5;  //trigger on ePWM1 SOCA/C
    AdcaRegs.ADCINTSEL1N2.bit.INT1SEL = 0;  //EOC0 is set to trigger ADCINT1
    AdcaRegs.ADCINTSEL1N2.bit.INT1E   = 1;  //enable INT1 flag
    AdcaRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;  //make sure INT1 flag is cleared

    AdcbRegs.ADCSOC0CTL.bit.CHSEL     = 2;  //SOC0 will convert pin A0//<-----------------------------------new
    AdcbRegs.ADCSOC0CTL.bit.ACQPS     = 14; //sample window is 15 SYSCLK cycles//<-----------------------------------new
    AdcbRegs.ADCSOC0CTL.bit.TRIGSEL   = 5;  //trigger on ePWM1 SOCA/C//<-----------------------------------new
    AdcbRegs.ADCINTSEL1N2.bit.INT1SEL = 0;  //EOC0 is set to trigger ADCINT1//<-----------------------------------new
    AdcbRegs.ADCINTSEL1N2.bit.INT1E   = 1;  //enable INT1 flag//<-----------------------------------new
    AdcbRegs.ADCINTFLGCLR.bit.ADCINT1 = 1;  //make sure INT1 flag is cleared//<-----------------------------------new

    EDIS;
}

Thanks for your help.

Regards,

Amin

Hi Whitney,

Thank you for your help. Both ADC channels working good.

What do you mean?:

"Also, there should be no need enable the interrupt for ADCB. The conversions should finish simultaneously and you're reading both results in the same ISR."

 I realized after adding a second ADC channel pwm generator (ePWM2) does not work. All changes that have been shown in a previous post and I have not changed the default program(rfft_adc_rt).

Regards,

Amin

Hi Amin,

Sorry for not getting back to you sooner. I was out of the office for several days. Do you have any updates on your project? Did you get ePWM2 running again?

Thanks,
Whitney

Hi Whitney,

Now it's working properly, but I do not know why it did not work the first time.
By adding a second channel sampling frequency is halved?

Thanks and regards,
Amin

The problem was memory allocation(.cmd file). solved. Thank you.
My last question is:
You've said in previous posts:
"Also, there should be no need enable the interrupt for ADCB. The conversions should finish simultaneously and you're reading both results in the same ISR."
What do you mean? I need to change part of the code ?
Thanks for your help.

Regards,
Amin

Thanks for your help.

Regards,
Amin