UART COM issue with f030r8

[user-stm]

Hello,

I am trying to use UART HAL with the stm32-f030r8 connected to the PC through a USB-TTL module.

The configuration is given below :

- The F030R8 has JP1 OFF, JP6 ON, JP5 on E5V.

- The USB-TTL is :

- The code is :

/* Includes ------------------------------------------------------------------*/
#include "main.h"

uint8_t test[] = "hello";
UART_HandleTypeDef huart2;

int main(void)
{

HAL_Init();

SystemClock_Config();

__USART2_CLK_ENABLE();
__GPIOA_CLK_ENABLE();

GPIO_InitTypeDef GPIO_InitStructure;

GPIO_InitStructure.Pin = GPIO_PIN_2;
GPIO_InitStructure.Mode = GPIO_MODE_AF_PP;
GPIO_InitStructure.Alternate = GPIO_AF1_USART2;
GPIO_InitStructure.Speed = GPIO_SPEED_HIGH;
GPIO_InitStructure.Pull = GPIO_NOPULL;
HAL_GPIO_Init(GPIOA, &GPIO_InitStructure);

GPIO_InitStructure.Pin = GPIO_PIN_3;
GPIO_InitStructure.Mode = GPIO_MODE_AF_OD;
HAL_GPIO_Init(GPIOA, &GPIO_InitStructure);

huart2.Instance = USART2;
huart2.Init.BaudRate = 9600;
huart2.Init.WordLength = UART_WORDLENGTH_8B;
huart2.Init.Parity = UART_PARITY_NONE ;
huart2.Init.Mode = UART_MODE_TX_RX;
huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;
huart2.Init.StopBits = UART_STOPBITS_1;

while (1){
HAL_UART_Transmit(&huart2,test,sizeof(test),HAL_MAX_DELAY);
HAL_Delay(1000);
}

}

Then, the putty configuration is 9600 baud, 8 data bits, 1 stop bits, no parity; no flow control.

But I can't see anything in the terminal...

Would you please have suggestions ?

Thanks for your help ! :)

[Pavel A.]

Disconnect the 5v wire (RED)  from the TTL module.

[user-stm]

My last question refers to the configuration without TTL module. I put it below again :

As it is mentioned that "By default, the USART2 communication between the target STM32 and ST-LINK MCU is enabled", if we forget the USB-TTL module ie we have a unique wire (USB Type-A to Mini-B cable) between the PC and the stm32, do you know why is still have anything on putty ?

Configuration with JP1 OFF, JP6 ON and JP5 on U5V and the following code :

/* Includes ------------------------------------------------------------------*/

#include "main.h"

UART_HandleTypeDef huart2;

uint8_t test[] = "hello";

void SystemClock_Config2(void);

static void MX_GPIO_Init(void);

static void MX_USART2_UART_Init(void);

int main(void)

{

  HAL_Init();

  SystemClock_Config();

  MX_GPIO_Init();

  MX_USART2_UART_Init();

  while (1)

  {

HAL_UART_Transmit(&huart2,test,sizeof(test),HAL_MAX_DELAY);

HAL_Delay(2000);

  }

}

void SystemClock_Config(void)

{

  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;

  if (HAL_RCC_OscConfig(&RCC_OscInitStruct) != HAL_OK)

  {

    Error_Handler();

  }

  RCC_ClkInitStruct.ClockType = RCC_CLOCKTYPE_HCLK|RCC_CLOCKTYPE_SYSCLK

                              |RCC_CLOCKTYPE_PCLK1;

  RCC_ClkInitStruct.SYSCLKSource = RCC_SYSCLKSOURCE_HSI;

  RCC_ClkInitStruct.AHBCLKDivider = RCC_SYSCLK_DIV1;

  RCC_ClkInitStruct.APB1CLKDivider = RCC_HCLK_DIV1;

  if (HAL_RCC_ClockConfig(&RCC_ClkInitStruct, FLASH_LATENCY_0) != HAL_OK)

  {

    Error_Handler();

  }

}

static void MX_USART2_UART_Init(void)

{

  huart2.Instance = USART2;

  huart2.Init.BaudRate = 9600;

  huart2.Init.WordLength = UART_WORDLENGTH_8B;

  huart2.Init.StopBits = UART_STOPBITS_1;

  huart2.Init.Parity = UART_PARITY_NONE;

  huart2.Init.Mode = UART_MODE_TX_RX;

  huart2.Init.HwFlowCtl = UART_HWCONTROL_NONE;

  huart2.Init.OverSampling = UART_OVERSAMPLING_16;

  huart2.Init.OneBitSampling = UART_ONE_BIT_SAMPLE_DISABLE;

  huart2.AdvancedInit.AdvFeatureInit = UART_ADVFEATURE_NO_INIT;

  if (HAL_UART_Init(&huart2) != HAL_OK)

  {

    Error_Handler();

  }

}

static void MX_GPIO_Init(void)

{

  __HAL_RCC_GPIOA_CLK_ENABLE();

}

void Error_Handler(void)

{

  __disable_irq();

  while (1)

  {

  }

}

[waclawek.jan]

On Nucleo (and Disco/EVAL), always start with reading the manual and looking at schematics for jumpers/solder bridges (SBxx) settings.

But maybe instead of changing the SB settings, you might want to leave them for the PA2/PA3 being used through the on-board STLink's VCP; and if you want for some reason to use the additional external USB-UART connection, use different pins/UART.

Also, as others said, you have to cross-connect the cable, Rx to Tx and vice versa (unless the USB-UART converter's author mislabelled the wires).

JW