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Can't read AnalogIn after wake up from deepsleep

Topic last updated 08 Jun 2015, by Kevin Holland. 1 reply
Håkon Bryn
21 May 2015

Hi

I use a Nucleo L152RE and try reading the ADC after a wake up from stop mode using the deepsleep function.

This returns 0.0000. I have tried in sleep mode, and this works fine.

I have also tried reinitializing the AnalogIn object.

Have no idea why this isn't working and would really appreciate if someone know how to solve this.

Håkon

Kevin Holland
08 Jun 2015

I saw the same issue, you have to reinitialize the HSI clock, because that's what the ADC is setup to use. The below code will get the HSI running again.

// Enable the HSI (to clock the ADC)
RCC_OscInitTypeDef RCC_OscInitStruct;
RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;
RCC_OscInitStruct.HSIState       = RCC_HSI_ON;
RCC_OscInitStruct.PLL.PLLState   = RCC_PLL_NONE;
HAL_RCC_OscConfig(&RCC_OscInitStruct);