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Analoge in not working on some STM processors.

Topic last updated 13 Feb 2016, by Petter Pripp. 2 replies
Nick Marsh
06 Feb 2016

The new STM32F series of chips uses ADC_3 and ADC_4, however, this is not available in "PeripheralPins.c"

I have devised these lines to be added into "PeripheralPins.c" after the ADC_3 has been declared.

    {PB_0,  ADC_3, STM_PIN_DATA(STM_MODE_ANALOG, GPIO_NOPULL, 0)}, // ADC3_IN12
    {PB_1,  ADC_3, STM_PIN_DATA(STM_MODE_ANALOG, GPIO_NOPULL, 0)}, // ADC3_IN1

but then the compiler complains that identifier ADC_3 is undefined :(

so I added these lines in PeripheralNames.h

,
    ADC_3 = (int)ADC3_BASE,
    ADC_4 = (int)ADC4_BASE

which, now it compiles. :)

PB1(ADC3-1) is working, but not PB0(ADC3-12), :(

Nick Marsh
09 Feb 2016

I added these to analogin_api.c

        case PB_0:
            sConfig.Channel = ADC_CHANNEL_12;
            break;
        case PB_1:
            sConfig.Channel = ADC_CHANNEL_1;
            break;

but PB_0 still does not work. :(

Petter Pripp
13 Feb 2016

ADC bugs on NUCLEO-F303K8 :

A0-A2 can not be used at same time as A3-A7. https://developer.mbed.org/questions/61977/Why-cant-I-initialize-ADC-AnalogIn-pins-/

Values is 5% too low. https://developer.mbed.org/questions/67943/AnalogIn-value-too-low/