How do i read multiplexed ADC Channels?

[PaulReichhold]

I am currently struggling to read all 4 main Channel from multiple ADC. I use a custom board file for a STM32F303CBT6 and more or less every thing works fine till I try to read the Multiplexed GPIOs on the ADCs. There are some problems that i am struggling with, one of them being that there is no example, where multiple channels are read. So I am not sure if I do it correctly and if that what I do is supposed to work with multiple channels.

One attempt that looked promising but failed.
Somehow the Stm crashes when i set the Interrupt for the second ADC Adc2::enableInterrupt(Adc2::Interrupt::EndOfRegularConversion);

uint16_t analog_adc_1[4];
uint16_t analog_adc_2[4];

uint8_t adc_1=0;
uint8_t adc_2=0;

int main() {

    Usart1::connect<GpioOutputA9::Tx>();
    Usart1::initialize<Board::SystemClock, 115200_Bd>();

    Board::initialize();
    Adc1::initialize(Adc1::ClockMode::Asynchronous, Adc1::Prescaler::Div2, Adc1::CalibrationMode::SingleEndedInputsMode, true);
    Adc1::enableInterruptVector(5);
    Adc1::enableInterrupt(Adc1::Interrupt::EndOfRegularConversion);
    Adc1::connect<GpioInputA0::In1,GpioInputA1::In2,GpioInputA2::In3,GpioInputA3::In4>();
    Adc1::setPinChannel<GpioInputA0>(Adc1::SampleTime::Cycles2);
    Adc1::startConversion();
    modm::delay_ms(10);

    Adc2::initialize(Adc2::ClockMode::Asynchronous, Adc2::Prescaler::Div2, Adc2::CalibrationMode::SingleEndedInputsMode, true);
    Adc2::enableInterruptVector(6);
    Adc2::enableInterrupt(Adc2::Interrupt::EndOfRegularConversion);
    Adc2::connect<GpioInputA4::In1,GpioInputA5::In2,GpioInputA6::In3,GpioInputA7::In4>();
    Adc2::setPinChannel<GpioInputA4>(Adc2::SampleTime::Cycles2);
    Adc2::startConversion();
    Board::LedUser::reset();
    modm::delay_ms(10);
    while(true){
        Board::LedUser::toggle();
        switch(adc_1){
            case 0:
                Adc1::setChannel(Adc1::Channel::Channel1);
                Adc1::startConversion();
                break;
            case 1:
                Adc1::setChannel(Adc1::Channel::Channel2);
                Adc1::startConversion();
                break;
            case 2:
                Adc1::setChannel(Adc1::Channel::Channel3);
                Adc1::startConversion();
                break;
            case 3:
                Adc1::setChannel(Adc1::Channel::Channel4);
                Adc1::startConversion();
                break;
        }
        switch(adc_2){
            case 0:
                Adc2::setChannel(Adc2::Channel::Channel1);
                Adc2::startConversion();
                break;
            case 1:
                Adc2::setChannel(Adc2::Channel::Channel2);
                Adc2::startConversion();
                break;
            case 2:
                Adc2::setChannel(Adc2::Channel::Channel3);
                Adc2::startConversion();
                break;
            case 3:
                Adc2::setChannel(Adc2::Channel::Channel4);
                Adc2::startConversion();
                break;
        }
        MODM_LOG_INFO << adc_1 << ": ADC_1 = " << analog_adc_1[adc_1] << modm::endl;
        MODM_LOG_INFO << adc_2 << ": ADC_2 = " << analog_adc_2[adc_2] << modm::endl;
        modm::delay_ms(1000);
    };
    return 0;
}

MODM_ISR(ADC1){
    if(Adc1::getInterruptFlags() & Adc1::InterruptFlag::EndOfRegularConversion){
        Adc1::acknowledgeInterruptFlag(Adc1::InterruptFlag::EndOfRegularConversion);
        analog_adc_1[adc_1] = Adc1::getValue();
        adc_1++;
        if(adc_1 > 3){
            adc_1 = 0;
        }
    }
}
MODM_ISR(ADC2){
    if(Adc2::getInterruptFlags() & Adc2::InterruptFlag::EndOfRegularConversion){
        Adc2::acknowledgeInterruptFlag(Adc2::InterruptFlag::EndOfRegularConversion);
        analog_adc_2[adc_2] = Adc2::getValue();
        adc_2++;
        if(adc_2 > 3){
            adc_2 = 0;
        }
    }
}

[salkinium]

I believe @rleh has more knowledge of the ADC and perhaps this particular issue.

[salkinium]

Sorry for the long wait, I was busy with work/uni.

As far as I can see, the F303CB only has a shared interrupt ADC1_2.
The ADC API is wrong to allow you to set separate interrupt, they will overwrite each other. See issue #409.

Try this:

MODM_ISR(ADC1_2)
{
    if(Adc1::getInterruptFlags() & Adc1::InterruptFlag::EndOfRegularConversion){
        Adc1::acknowledgeInterruptFlag(Adc1::InterruptFlag::EndOfRegularConversion);
        analog_adc_1[adc_1] = Adc1::getValue();
        adc_1++;
        if(adc_1 > 3){
            adc_1 = 0;
        }
    }
    if(Adc2::getInterruptFlags() & Adc2::InterruptFlag::EndOfRegularConversion){
        Adc2::acknowledgeInterruptFlag(Adc2::InterruptFlag::EndOfRegularConversion);
        analog_adc_2[adc_2] = Adc2::getValue();
        adc_2++;
        if(adc_2 > 3){
            adc_2 = 0;
        }
    }
}

The STM32 may crash or restart if an interrupt is not hooked correctly. It's unfortunate that there isn't a warning about providing the wrong handler. I'll try to see what I can do (it's difficult since this would need to happen at link time).

I strongly recommend overwriting the modm_abandon function, which will tell you about a lot of failures, especially in debug profile.
You can adapt the modm_abandon function from the modm BSP files.

[rleh]

I believe @rleh has more knowledge of the ADC and perhaps this particular issue.

Sorry for the delay. I was busy studying for my exams, and now I have a lot of unread github notifications.

The STM32F303 series have the same ADC IP as the STM32G4 series, which I started adding modm support for. Maybe I have broken the STM32F303 ADC driver while adding STM32G4 support in 1ab7834 (#287)?
Could you check-out a modm version before 1ab7834 and check the problem?

While testing the STM32G4 ADC driver from #324 on real hardware, I encountered unexpected problems that I have not yet investigated in detail.

See also #409 and #324.