Having Issues with ADC configuration STM32L011K4T6

[scarface_the_fox]

Hello,

I have tried for the last couple of days to get use 2 pots to change the frequency and duty cycle of a PWM signal using "Bare Metal" programming due to the flash limitation of the STM32L011K4T6 I rapidly ran out of space using HAL and was not able to make this fit. I am using the STM32 Nucleo-L011K4 Board

The Issue I am having is under HAL I got the STM32L011K4T6 to read from 1 Pot and output a variable frequency PWM signal or 2 Pots and no PWM Signal due to size limitations. So I switched to Bare Metal Programming and have had nothing but issues even though I set the registers the same and have followed multiple different guides online but every time I wait for the ADC_ISR_EOC flag to be set it gets set as soon as I trigger ADC_CR_ADCSTART but then disappears as soon as I get into the while variable so it forms an infinite loop.

at this point I do not know what I am doing wrong.

Any help would be greatly appreciated. 

Code Below

uint32_t freq = 0;
float dc = 0;

int main(void)
{
  HAL_Init();
  SystemClock_Config();
  MX_GPIO_Init();
  MX_ADC_Init();
  MX_TIM2_Init();
  HAL_TIM_PWM_Start(&htim2, TIM_CHANNEL_1);
  ADC1->CR    |=  ( ADC_CR_ADVREGEN );
  HAL_ADCEx_Calibration_Start(&hadc,ADC_SINGLE_ENDED);
  if (1)
  {
    ADC1->CR  |=  ( ADC_CR_ADCAL );
    while ( ADC1->CR & ADC_CR_ADCAL ) {};
  }
  while (1)
  {
      ADC1->CHSELR = 0;
      ADC1->CHSELR |= ADC_CHSELR_CHSEL3;	  
      ADC1->CR |= ADC_CR_ADEN;
	  ADC1->CR |= ADC_CR_ADSTART;
	  while(!(ADC1->ISR & ADC_ISR_EOC)){}
	  freq = ADC1->DR;
	  ADC1->CR &= ADC_CR_ADSTART;

	  ADC1->CHSELR = 0;
	  ADC1->CHSELR |= ADC_CHSELR_CHSEL7;
	  ADC1->CR |= ADC_CR_ADEN;
	  ADC1->CR |= ADC_CR_ADSTART;
	  while(!(ADC1->ISR & ADC_ISR_EOC)){int a = a;}
	  dc = ADC1->DR;
	  ADC1->CR &= ADC_CR_ADEN;
	  ADC1->CR &= ADC_CR_ADSTART;
	  dc = (dc - 0.0) * (4095.0 - 0.0) / (4095.0 - 0.0) + 0.0;
      freq = freq * 65535;
      freq = freq / 4095;
      if(dc <= freq)
      {
		  TIM2->ARR = freq - 1;
		  TIM2->CCR1 = (freq / dc);
      }
  }
}




void MX_GPIO_Init(void)
{
	GPIOA->MODER |= (3 << (3*2));
	GPIOA->MODER |= (3 << (7*2));
}




/**
  * @brief System Clock Configuration
  * @retval None
  */
void SystemClock_Config(void)
{
  RCC->CR = 0x3000305;
  RCC->AHBENR = 0x100;
  RCC->APB2ENR = 0x400201;
  RCC->APB1ENR = 0x10000001;
  RCC->IOPENR = 0x5;
}


static void MX_ADC_Init(void)
{
	RCC->APB2ENR |= (RCC_APB2ENR_ADCEN);
	/*
	ADC1->CR &= ~ADC_CR_ADVREGEN;
	for(int i =0;i<10*48/4;i++){i=i;}
	ADC1->CR |= ADC_CR_ADVREGEN;
	ADC1->CR |= ADC_CR_ADCAL;
	while((ADC1->CR & ADC_CR_ADCAL) != 0){int a = a;}
	ADC1->CFGR2 &= ~ADC_CFGR2_CKMODE;
	ADC->CCR |= ADC_CCR_TSEN;
	ADC1->CHSELR |= (1 << 3);
	ADC1->CHSELR |= (1 << 7);
//	ADC1->CR = 0x10000000;
//	ADC1->CFGR1 = 0;
//	ADC1->CFGR2 = 0x40000000;
	ADC1->SMPR = 0x2;*/
}


static void MX_TIM2_Init(void)
{
	TIM2->CR1 = 0x281;
	TIM2->SR = 0x1f;
	TIM2->CCMR1 = 0x68;
	TIM2->CCER = 0x1;
	TIM2->PSC = 0x14;
	TIM2->DMAR = 0x281;
}

[ONadr.1]

When you used HAL, did you try to optimize the compiler for code size? I had a similar problem and after turning on optimization, the volume decreased by a third.

[scarface_the_fox]

I did try to follow guides on how to optimize the compiler but most of it was out of date and most were conflicting and confusing. if it helps I am using STM32cubeIDE Version 1.13.2. But yeah I was still 3Kb over the flash storage.

If it helps just so you do not have to look for the specs it has 16kb flash and 2kb ram.

[ONadr.1 · Accepted solution]

Optimizing is in main menu. Navigation is:

Project-->Properties-->C/C++Build-->Settings-->MCU GCC Compiler-->Optimization

and here settings Optimization level  --> Optimize for size (-Os)

[TDK]

> ADC1->CR &= ADC_CR_ADSTART;

This clears all flags except ADSTART. You probably want:

ADC1->CR &= ~ADC_CR_ADSTART;

Consider using SET_BIT and CLEAR_BIT instead to avoid typos like that.

[scarface_the_fox]

I tried this and it helped a lot I was able to get the code to 14.9kb and now my HAL code works.

Thanks very much!.