ADC Libraries

[fpistm]

From @palmerr23 on April 26, 2017 5:23

Frederic,

I've been testing the advanced ADC\DAC modes (beyond single conversion, polling) using the templates from STM32Cube_FW_F4_V1.15.0\Projects\STM324x9I_EVAL\Examples\ADC\ and \DAC\

When using these other analog routines, HAL_ADC_MspInit() etc need to be customised for each configuration.

Now I'm trying out the dual-interleaved mode, it has become clear that the code in analog.c is just an initial test.

As HAL_ADC_MspInit() needs to be customised for each configuration, I'm looking at hiding the MSP_Init functions in analog.c at the system level and moving the code up to a library. The Init functions can then be customised for each mode.

When I tried this, other functions break - like dac_stop() and pwm_stop(). I think I'll be able to leave them in analog.c

Give me a few days and I'll have something workable.

Single-Polling and Single-interrupt are working already, using pretty much standard code from the Cube libraries, next up is dual-interleaved

Richard

Copied from original issue: fpistm/Arduino_Core_STM32F4#11

[fpistm]

From @palmerr23 on May 6, 2017 7:3

Frederic,

I've tested a number of ADC modes - polling, interrupt, DMA.

Example files are in https://github.com/palmerr23/Black-F407VET6-cube/tree/master/examples

Currently debugging Dual Mode Interleaved (edit: now working).

[fpistm]

Proposed to move on the new repo Arduino_Core_STM32 as this one is deprecated. (same code).

[fpistm]

From @palmerr23 on May 24, 2017 8:36

Frederic, Fine by me. I'm shifting across to the new core also.

[tve]

Q: instead of adding stuff to the arduino-compatible analogRead have you considered using a different ADC API altogether? Leave analogRead for compatibility purposes but make something better available for advanced uses. The main benefit I see is that a new API allows set-up/tear-down to be separated from the actual reading function. For example, https://github.com/rogerclarkmelbourne/Arduino_STM32/tree/master/STM32F1/libraries/STM32ADC looks pretty darn nice to me and should not be a ton of work to port to LL (if that has all the functionality necessary).

[fpistm]

Yes, this is what I would like.
Like for timer: HardwareTimer...

[tve]

Ok, I got a very minimal first version working on STM32L0 doing just single conversions (plus Vcc and Temp). See https://github.com/tve/goobies/tree/master/libraries/STM32ADC/src
I would appreciate a review and feedback. I'm not sure how to really handle the clock stuff without introducing a lot of complexity and a lot of code...
If this is an interesting direction, I'm happy to get a PR going.

A simple test sketch I'm using to print ADC value for one channel, Vcc, and temperature:

// ADC tester - Displays ADC value
#include <Arduino.h>
#include <stdio.h>
#include <STM32ADC.h>

STM32ADC adc(ADC1);

void setup() {
    pinMode(LED, OUTPUT);
    digitalWrite(LED, LOW);

    Serial.begin(115200);
    delay(10);
    printf("===== ADC tester starting\n");

    if (!adc.begin(PB1)) printf("ADC.begin() failed!\n");
    pinMode(PB1, INPUT);
}

uint8_t led=0;

void loop() {
    adc.startConversion();
    uint32_t v = adc.read();
    uint32_t vcc = adc.measureVcc();
    int16_t temp = adc.measureTemp();
    printf("ADC: %lu, vcc: %lumV temp: %dC\n", v, vcc, temp);
    delay(1000);
}

Output looks something like:

ADC: 2057, vcc: 3260mV temp: 21C
ADC: 2055, vcc: 3258mV temp: 21C
ADC: 2057, vcc: 3258mV temp: 21C
ADC: 2057, vcc: 3258mV temp: 21C
ADC: 2058, vcc: 3247mV temp: 21C
ADC: 2061, vcc: 3260mV temp: 21C
ADC: 2060, vcc: 3258mV temp: 21C
ADC: 2057, vcc: 3258mV temp: 21C
ADC: 2057, vcc: 3258mV temp: 21C

[Alteregoxxx]

From @palmerr23 on May 6, 2017 7:3

Frederic,

I've tested a number of ADC modes - polling, interrupt, DMA.

Example files are in https://github.com/palmerr23/Black-F407VET6-cube/tree/master/examples

Currently debugging Dual Mode Interleaved (edit: now working).

@fpistm
Hi Frederic, I see in your examples that you're able to define HAL_ADC_Msp_Init() conserving, at the same time, the ability to use all the "builtin" Arduino functions such, for example, Serial.print().

I would need to do the same in PlatformIO, using your official STM32 Core Arduino and an STM32F407VGT6 (STM32F4 Discovery board).
Like you said, one need to redefine HAL_ADC_Msp_Init() for being able to use the advanced ADC modes (interrupt, DMA, interleaved etc etc) but, obviously, if I try to (re)define my own HAL_ADC_Msp_Init() the compiler complains that that function is already defined in your implementation of Analog.c

Is there a way to circumvent the obstacle?

Moreover, in trying to use the adc in regular conversion interrupt mode, I've also tried with an "unconventional" way trying circumvent the obstacle:

1. created handle and a configuration for my adc:
   ADC_Handle_Typedef MyAdcHandle; ADC_ChannelConfTypeDef MyAdcChannelConf = {};
2. Initialized all the handle members:
   MyAdcHandle.Instance = ADC1
   MyAdcHandle.Init.ClockPrescaler = ADC_CLOCKPRESCALER_PCLK_DIV4;
   My_AdcHandle.Init.Resolution = ADC_RESOLUTION_12B; etc etc etc
   3)Called HAL_ADC_Init(&MyAdcHandle)--> this will call your HAL_ADC_Msp_Init(), initializing __HAL_RCC_ADC1_CLK_ENABLE(); etc etc etc

/CIRCUMVENT PART*****/
4)Added the following lines of code:
HAL_NVIC_SetPriority(ADC_IRQn, 0, 0);//HAL_NVIC_SetPriority(ADC_IRQn, 0, 0);
HAL_NVIC_EnableIRQ(ADC_IRQn);
/END CIRCUMVENT PART*/

5)Created the HAL_ADC_ConvCpltCallback() and ADC_IRQHandler() functions and correctly managed them
6)Initializied the pin of the adc I want to use using:
GPIO_InitTypeDef gpioInit;
__GPIOC_CLK_ENABLE();
gpioInit.Pin = GPIO_PIN_1;
gpioInit.Mode = GPIO_MODE_ANALOG;
gpioInit.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOC, &gpioInit);

....and......it doesn't work when using Arduino framework in PlatformIO but it works when using HAL framework in PlatformIO

Please, any suggestion is very very welcome!