IR Sensor with Blue Pill using STM32CubeIDE

Prerequisites

This project assumes you have already installed STM32CubeIDE. You need to have previously done a basic blink sketch with blue-pill using STM32CubeIDE. I have made a complete video from installing STM32CubeIDE to LED blink program. You can watch it by clicking this link. https://www.youtube.com/watch?v=kXg467nVd_A

Wiring Diagram

STM32CubeIDE Settings

Click RCC → High Speed Clock (HSE) to Crystal/Ceramic Resonator

Click Clock Configuration tab → HCLK (MHz) to 72

Click Pinout and Configuration tab

Click Timer → Click TIM1 →

Clock Source set to Internal Clock

Configuration → Parameter Settings →

Prescaler set to 71

Set PB11 to GPIO_EXTI11

Click System Core → Click NVIC → EXTI line[15-10] interrupt → Enabled (Tick)

Click System Core → Click GPIO → Select PB11 → GPIO Mode to ...

External Interrupt Mode with Falling Edge trigger detection

Click connectivity --> Click I2C1

For I2C select I2C

Configuration --> Parameter Settings

For I2C speed select Fast Mode

Libraries

Inside Core/Inc Folder

Inside Core/Src Folder

Additional code on top of STM32CubeIDE generated code

/* USER CODE BEGIN Includes */
#include "fonts.h"
#include "ssd1306.h"
/* USER CODE END Includes */

/* USER CODE BEGIN PV */
uint32_t tempCode;
uint8_t bitIndex;
uint8_t cmd;
uint8_t cmdli;
uint32_t code;
/* USER CODE END PV */

  /* USER CODE BEGIN 2 */
  SSD1306_Init();
  HAL_TIM_Base_Start(&htim1);
  __HAL_TIM_SET_COUNTER(&htim1, 0);
  /* USER CODE END 2 */

/* USER CODE BEGIN 4 */
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
  if(GPIO_Pin == GPIO_PIN_11)
  {
    if (__HAL_TIM_GET_COUNTER(&htim1) > 8000)
    {
      tempCode = 0;
      bitIndex = 0;
    }
    else if (__HAL_TIM_GET_COUNTER(&htim1) > 1700)
    {
      tempCode |= (1UL << (31-bitIndex));   // write 1
      bitIndex++;
    }
    else if (__HAL_TIM_GET_COUNTER(&htim1) > 1000)
    {
      tempCode &= ~(1UL << (31-bitIndex));  // write 0
      bitIndex++;
    }
    if(bitIndex == 32)
    {
      cmdli = ~tempCode; // Logical inverted last 8 bits
      cmd = tempCode >> 8; // Second last 8 bits
      if(cmdli == cmd) // Check for errors
      {
        code = tempCode; // If no bit errors
        // Do your main work HERE
        SSD1306_Clear();
        SSD1306_GotoXY (0, 20);
        char snum[10];
        itoa(code, snum, 10);
        SSD1306_Puts (snum, &Font_11x18, 1);				
        SSD1306_UpdateScreen();
      }
      bitIndex = 0;
    }
    __HAL_TIM_SET_COUNTER(&htim1, 0);
  }
}
/* USER CODE END 4 */

Updated code for USER CODE 4

/* USER CODE BEGIN 4 */
void HAL_GPIO_EXTI_Callback(uint16_t GPIO_Pin)
{
  if(GPIO_Pin == GPIO_PIN_11)
  {
    if (__HAL_TIM_GET_COUNTER(&htim1) > 8000)
    {
      tempCode = 0;
      bitIndex = 0;
    }
    else if (__HAL_TIM_GET_COUNTER(&htim1) > 1700)
    {
      tempCode |= (1UL << (31-bitIndex));   // write 1
      bitIndex++;
    }
    else if (__HAL_TIM_GET_COUNTER(&htim1) > 1000)
    {
      tempCode &= ~(1UL << (31-bitIndex));  // write 0
      bitIndex++;
    }
    if(bitIndex == 32)
    {
      cmdli = ~tempCode; // Logical inverted last 8 bits
      cmd = tempCode >> 8; // Second last 8 bits
      if(cmdli == cmd) // Check for errors
      {
        code = tempCode; // If no bit errors
        // Do your main work HERE
        SSD1306_Clear();
        SSD1306_GotoXY (0, 20);
        switch (code)
        {
          case (16753245):
            SSD1306_Puts ("CH-", &Font_16x26, 1);
            break;

          case (16736925):
            SSD1306_Puts ("CH", &Font_16x26, 1);
            break;

          case (16769565):
            SSD1306_Puts ("CH+", &Font_16x26, 1);
            break;

          case (16720605):
            SSD1306_Puts ("|<<", &Font_16x26, 1);
            break;

          case (16712445):
            SSD1306_Puts (">>|", &Font_16x26, 1);
            break;

          case (16761405):
            SSD1306_Puts (">||", &Font_16x26, 1);
            break;

          case (16769055):
            SSD1306_Puts ("-", &Font_16x26, 1);
            break;

          case (16754775):
            SSD1306_Puts ("+", &Font_16x26, 1);
            break;

          case (16748655):
            SSD1306_Puts ("EQ", &Font_16x26, 1);
            break;

          case (16738455):
            SSD1306_Puts ("0", &Font_16x26, 1);
            break;

          case (16750695):
            SSD1306_Puts ("100+", &Font_16x26, 1);
            break;

          case (16756815):
            SSD1306_Puts ("200+", &Font_16x26, 1);
            break;

          case (16724175):
            SSD1306_Puts ("1", &Font_16x26, 1);
            break;

          case (16718055):
            SSD1306_Puts ("2", &Font_16x26, 1);
            break;

          case (16743045):
            SSD1306_Puts ("3", &Font_16x26, 1);
            break;

          case (16716015):
            SSD1306_Puts ("4", &Font_16x26, 1);
            break;

          case (16726215):
            SSD1306_Puts ("5", &Font_16x26, 1);
            break;

          case (16734885):
            SSD1306_Puts ("6", &Font_16x26, 1);
            break;

          case (16728765):
            SSD1306_Puts ("7", &Font_16x26, 1);
            break;

          case (16730805):
            SSD1306_Puts ("8", &Font_16x26, 1);
            break;

          case (16732845):
            SSD1306_Puts ("9", &Font_16x26, 1);
            break;

          default :
            break;
        }
      SSD1306_UpdateScreen();
      }
    bitIndex = 0;
    }
  __HAL_TIM_SET_COUNTER(&htim1, 0);
  }
}
/* USER CODE END 4 */