STM32F103C8T6 Program not working and USB not recognized

[JTAPIE]

Hello,

I found this schematic and layout with a stm32f103c8t6. I ordered it and wanted to programm it.

With stm32cubeprogrammer I detect the stm32 no problem via ST-LINK.

Same with stm32cubeide I can download successfully the code.

But now the problem is that eventhough the code is downloaded successfully the simple program to blink a pin to which I attach a diode is not working and I don’t see why.

I also want to be able to send data from my computer to the STM32 with USB but after downloading the code with "usb_device.h" and MX_USB_DEVICE_Init();, deconnecting ST-LINK and connecting with USB the STM32 is not recognized by the computer.

Any idea of what I could look for or ressources ?

If you see any problem in the design please tell me.

Regards,

Jean

[Peter BENSCH]

Blue Pill and other coloured ‘pills’ are not a product of STMicroelectronics and use counterfeit STM32F103, especially for the Blue Pill. STM32 tools can therefore not support this and reject a connection with it.

Solution: either ask the counterfeiters for help or get a NUCLEO, e.g. the NUCLEO-F103RB from an authorised dealer.

Hope that helps?

Good luck!
/Peter

[Peter BENSCH]

Oops, I replied too quickly and thought you were using a Blue Pill. Hang on, let me take a closer look at your documentation.

Where did you buy the STM32F103C8T6?

Regards
/Peter

[JTAPIE]

Hi, the manufacturer did the assembly so I don't know where they bought it but the MCU doesn't seem to be counterfeit. It has the logo ST on it.

Regards,

Jean

[Peter BENSCH]

Unfortunately, our logo on an MCU does not prove at all that it is an original. STM32F103C8T6 in particular have been counterfeited on a large scale for several years, including the logo.

In cases where you cannot be completely sure that the seller is selling original goods (Aliexress, Ebay, etc.), it is advisable to check this with a test programme. You can also find tips on this here in the community, e.g. here or there.

Regards
/Peter

[Peter BENSCH]

Which LED you want to flash?

I don't see any LED on PA9 that you are trying to control with your code?

[JTAPIE]

It is a LED connected to the pin A9 and to GND, i checked that the diode was working when connected to +3.3V to GND it is the case so the diode is not the problem.

[Andrew Neil]

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@JTAPIE wrote:

It is a LED connected to the pin A9 and to GND

---

No series resistor?

[Andrew Neil]

Please see How to insert source code - not as screenshots.

 

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@JTAPIE wrote:

the simple program to blink a pin to which I attach a diode is not working

---

Please show how you are attaching the LED.

"Not working" tells us little: does the LED not light at all? stay on permanently? burst into flames?

 

---

@JTAPIE wrote:

Any idea of what I could look for or resources ?

---

Use the debugger to see what the code is actually doing.

Certainly, get the LED working before moving on to advanced stuff like USB!

[JTAPIE]

/* USER CODE BEGIN Header */
/**
 ******************************************************************************
 * @file : main.c
 * @brief : Main program body
 ******************************************************************************
 * @attention
 *
 * Copyright (c) 2025 STMicroelectronics.
 * All rights reserved.
 *
 * This software is licensed under terms that can be found in the LICENSE file
 * in the root directory of this software component.
 * If no LICENSE file comes with this software, it is provided AS-IS.
 *
 ******************************************************************************
 */
/* USER CODE END Header */
/* Includes ------------------------------------------------------------------*/
#include "main.h"
#include "usb_device.h"

/* Private includes ----------------------------------------------------------*/
/* USER CODE BEGIN Includes */

/* USER CODE END Includes */

/* Private typedef -----------------------------------------------------------*/
/* USER CODE BEGIN PTD */

/* USER CODE END PTD */

/* Private define ------------------------------------------------------------*/
/* USER CODE BEGIN PD */

/* USER CODE END PD */

/* Private macro -------------------------------------------------------------*/
/* USER CODE BEGIN PM */

/* USER CODE END PM */

/* Private variables ---------------------------------------------------------*/

/* USER CODE BEGIN PV */

/* USER CODE END PV */

/* Private function prototypes -----------------------------------------------*/
void SystemClock_Config(void);
static void MX_GPIO_Init(void);
/* USER CODE BEGIN PFP */

/* USER CODE END PFP */

/* Private user code ---------------------------------------------------------*/
/* USER CODE BEGIN 0 */

/* USER CODE END 0 */

/**
 * @brief The application entry point.
 * @retval int
 */
int main(void)
{
 /* USER CODE BEGIN 1 */

 /* USER CODE END 1 */

 /* MCU Configuration--------------------------------------------------------*/

 /* Reset of all peripherals, Initializes the Flash interface and the Systick. */
 HAL_Init();

 /* USER CODE BEGIN Init */

 /* USER CODE END Init */

 /* Configure the system clock */
 SystemClock_Config();

 /* USER CODE BEGIN SysInit */

 /* USER CODE END SysInit */

 /* Initialize all configured peripherals */
 MX_GPIO_Init();
 MX_USB_DEVICE_Init();
 /* USER CODE BEGIN 2 */

 /* USER CODE END 2 */

 /* Infinite loop */
 /* USER CODE BEGIN WHILE */
 while (1)
 {
 /* USER CODE END WHILE */
	 HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_SET);
	 HAL_Delay(400);
	 // LED OFF
	 HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_RESET);
	 HAL_Delay(400);
 /* USER CODE BEGIN 3 */
 }
 /* USER CODE END 3 */
}

/**
 * @brief System Clock Configuration
 * @retval None
 */
void SystemClock_Config(void)
{
 RCC_OscInitTypeDef RCC_OscInitStruct = {0};
 RCC_ClkInitTypeDef RCC_ClkInitStruct = {0};
 RCC_PeriphCLKInitTypeDef PeriphClkInit = {0};

 /** Initializes the RCC Oscillators according to the specified parameters
 * in the RCC_OscInitTypeDef structure.
 */
 RCC_OscInitStruct.OscillatorType = RCC_OSCILLATORTYPE_HSE;
 RCC_OscInitStruct.HSEState = RCC_HSE_ON;
 RCC_OscInitStruct.HSEPredivValue = RCC_HSE_PREDIV_DIV1;
 RCC_OscInitStruct.HSIState = RCC_HSI_ON;
 RCC_OscInitStruct.PLL.PLLState = RCC_PLL_ON;
 RCC_OscInitStruct.PLL.PLLSource = RCC_PLLSOURCE_HSE;
 RCC_OscInitStruct.PLL.PLLMUL = RCC_PLL_MUL3;
 if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)
 {
 Error_Handler();
 }

 /** Initializes the CPU, AHB and APB buses clocks
 */
 RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK
 |RCC_CLOCKTYPE_PCLK1|RCC_CLOCKTYPE_PCLK2;
 RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSE;
 RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;
 RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;
 RCC_ClkInitStruct.APB2CLKDivider = RCC_HCLK_DIV1;

 if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)
 {
 Error_Handler();
 }
 PeriphClkInit.PeriphClockSelection = RCC_PERIPHCLK_USB;
 PeriphClkInit.UsbClockSelection = RCC_USBCLKSOURCE_PLL;
 if (HAL_RCCEx_PeriphCLKConfig(&PeriphClkInit) != HAL_OK)
 {
 Error_Handler();
 }
}

/**
 * @brief GPIO Initialization Function
 * @PAram None
 * @retval None
 */
static void MX_GPIO_Init(void)
{
 GPIO_InitTypeDef GPIO_InitStruct = {0};
/* USER CODE BEGIN MX_GPIO_Init_1 */
/* USER CODE END MX_GPIO_Init_1 */

 /* GPIO Ports Clock Enable */
 __HAL_RCC_GPIOD_CLK_ENABLE();
 __HAL_RCC_GPIOA_CLK_ENABLE();

 /*Configure GPIO pin Output Level */
 HAL_GPIO_WritePin(GPIOA, GPIO_PIN_9, GPIO_PIN_RESET);

 /*Configure GPIO pin : PA9 */
 GPIO_InitStruct.Pin = GPIO_PIN_9;
 GPIO_InitStruct.Mode = GPIO_MODE_OUTPUT_PP;
 GPIO_InitStruct.Pull = GPIO_NOPULL;
 GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_LOW;
 HAL_GPIO_Init(GPIOA, &GPIO_InitStruct);

/* USER CODE BEGIN MX_GPIO_Init_2 */
/* USER CODE END MX_GPIO_Init_2 */
}

/* USER CODE BEGIN 4 */

/* USER CODE END 4 */

/**
 * @brief This function is executed in case of error occurrence.
 * @retval None
 */
void Error_Handler(void)
{
 /* USER CODE BEGIN Error_Handler_Debug */
 /* User can add his own implementation to report the HAL error return state */
 __disable_irq();
 while (1)
 {
 }
 /* USER CODE END Error_Handler_Debug */
}

#ifdef USE_FULL_ASSERT
/**
 * @brief Reports the name of the source file and the source line number
 * where the assert_param error has occurred.
 * @PAram file: pointer to the source file name
 * @PAram line: assert_param error line source number
 * @retval None
 */
void assert_failed(uint8_t *file, uint32_t line)
{
 /* USER CODE BEGIN 6 */
 /* User can add his own implementation to report the file name and line number,
 ex: printf("Wrong parameters value: file %s on line %d\r\n", file, line) */
 /* USER CODE END 6 */
}
#endif /* USE_FULL_ASSERT */

[Andrew Neil]

So have you used the debugger?

[Andrew Neil]

Did you get your own board working?

https://community.st.com/t5/stm32cubeprogrammer-mcus/stm32f103c8t6-no-usb-detection/td-p/739695 

[JTAPIE]

No that's why I tried to do this new PCB.