STM32F103C6 HAL_GPIO_ReadPin() doesn't work properly (I think).

[RedRabbit90]

Hi there.

I'm trying to read a button status using STM32F103C6 (fake BluePill) with STM32CubeIDE 1.13.1 and/or using Labcenter Proteus to simulate. However, the reading does not work correctly. I would like some help to understand what is missing.

My poor code:

#include "stm32f1xx_hal.h"

#define LED_Pin GPIO_PIN_13

#define LED_GPIO_Port GPIOC

#define BUTTON_Pin GPIO_PIN_1

#define BUTTON_GPIO_Port GPIOA

int main(void)

{

  HAL_Init();

  RCC_OscInitTypeDef RCC_OscInitStruct = {0};

  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;

  RCC_OscInitStruct.HSIState = RCC_HSI_ON;

  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;

  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;

  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;

  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;

  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;

  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  GPIO_InitTypeDef GPIO_InitStruct = {0};

  __HAL_RCC_GPIOC_CLK_ENABLE();

  __HAL_RCC_GPIOA_CLK_ENABLE();

  HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_RESET);

  GPIO_InitStruct.Pin = LED_Pin;

  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;

  GPIO_InitStruct.Pull = GPIO_NOPULL;

  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;

  HAL_GPIO_Init(LED_GPIO_Port, &GPIO_InitStruct);

  GPIO_InitStruct.Pin = BUTTON_Pin;

  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;

  GPIO_InitStruct.Pull = GPIO_PULLUP;

  HAL_GPIO_Init(BUTTON_GPIO_Port, &GPIO_InitStruct);

  while (1)

  {

  if(HAL_GPIO_ReadPin(BUTTON_GPIO_Port, BUTTON_Pin)== GPIO_PIN_RESET){

  HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_SET);

  }else{

  HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_RESET);

  }

  HAL_Delay(100);

  }

}

The schematic is so basic: button pin in GND, 1K resistor Pull UP.

Thanks in advance.

[TDK]

Your code is fine, and there's no bug in HAL_GPIO_ReadPin.

Recheck your connections. Remove the button and jump PA1 directly to GND to verify that works.

Toggle the LED separately to verify that it works.

[RedRabbit90]

Hi TDK...

"Toggle the LED separately to verify that it works."
It was the first item that I did, the toggle the LED separately is worked fine!

"Recheck your connections. Remove the button and jump PA1 directly to GND to verify that works."
It was the second item that I did, before open this topic.

I even changed to the multiple pins ofs buttons, PA0,PA1, PA2,PA3,PA4,PA5,PA6,PA7,PB1... same issue.

Thanks.

[TDK]

Okay, good. If both of those tests worked, that would indicate the problem is with your button or button wiring.

[RedRabbit90 · Accepted solution]

After trying for a long time, I got a solution out of nowhere...
Now it's only working in the real hardware (probably Proteus is not simulating correctly). The code is basically the same.

#include "stm32f1xx_hal.h"

#define LED_Pin GPIO_PIN_13

#define LED_GPIO_Port GPIOC

#define BUTTON_Pin GPIO_PIN_1

#define BUTTON_GPIO_Port GPIOA

int main(void)

{

  HAL_Init();

  RCC_OscInitTypeDef RCC_OscInitStruct = {0};

  RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};

  RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSI;

  RCC_OscInitStruct.HSIState = RCC_HSI_ON;

  RCC_OscInitStruct.HSICalibrationValue = RCC_HSICALIBRATION_DEFAULT;

  RCC_OscInitStruct.PLL.PLLState = RCC_PLL_NONE;

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK|RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;

  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;

  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;

  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;

  RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

  GPIO_InitTypeDef GPIO_InitStruct = {0};

  __HAL_RCC_GPIOC_CLK_ENABLE();

  __HAL_RCC_GPIOA_CLK_ENABLE();

  HAL_GPIO_WritePin(LED_GPIO_Port, LED_Pin, GPIO_PIN_RESET);

  HAL_GPIO_WritePin(LED_B1_GPIO_Port, LED_B1_Pin, GPIO_PIN_SET);

  GPIO_InitStruct.Pin = LED_Pin;

  GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;

  GPIO_InitStruct.Pull = GPIO_NOPULL;

  GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;

  HAL_GPIO_Init(LED_GPIO_Port, &GPIO_InitStruct);

  GPIO_InitStruct.Pin = BUTTON_Pin;

  GPIO_InitStruct.Mode = GPIO_MODE_INPUT;

  GPIO_InitStruct.Pull = GPIO_PULLUP; // The concept is different for other types of MCUs.

  HAL_GPIO_Init(BUTTON_GPIO_Port, &GPIO_InitStruct);

  while (1)

  {

  if(HAL_GPIO_ReadPin(BUTTON_GPIO_Port, BUTTON_Pin)){

  HAL_GPIO_WritePin(LED_Pin, LED_GPIO_Port, GPIO_PIN_SET);   

  }else{

  HAL_GPIO_WritePin(LED_Pin, LED_GPIO_Port, GPIO_PIN_RESET);   

  }

  HAL_Delay(100);

  }

}

Thanks for help me!

[RedRabbit90]

The wire and button is ok! Checked twice.