Solved
Why SMT32L031x UART pins do not work?
Hello, I have a custom board with a SMT32L031F6P6 on it: PA2 and PA3 USART2 channel seems not to work even if they are correctly set in the .ioc file.
I have tried the same code on the NUCLEO-L031K6 board using VCP-TX and VCP-RX (PA2 e PA15) default pins and it works correctly, but if I move the UART pins to the Arduino-compatible ones, PA9 and PA10, it dosen't work anymore.
What am I doing wrong? The UM1956 says that "Only one USART is available and it is shared between Arduino Nano and VCP. The selection is done by remapping (no hardware configuration to change)." but I think something is missing.
This is the working code, in CubeIDE v.11.0:
...
#ifdef __GNUC__
/* With GCC, small printf (option LD Linker->Libraries->Small printf
set to 'Yes') calls __io_putchar() */
#define PUTCHAR_PROTOTYPE int __io_putchar(int ch)
#else
#define PUTCHAR_PROTOTYPE int fputc(int ch, FILE *f)
#endif /* __GNUC__ */
...
int main(void)
{
HAL_Init();
SystemClock_Config();
MX_GPIO_Init();
MX_USART2_UART_Init();
while (1)
{
printf("hello\r\n");
HAL_Delay(500);
}
}
...
static void MX_USART2_UART_Init(void)
{
huart2.Instance = USART2;
huart2.Init.BaudRate = 115200;
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();
}
}
...
PUTCHAR_PROTOTYPE
{
/* Place your implementation of fputc here */
/* e.g. write a character to the USART2 and Loop until the end of transmission */
HAL_UART_Transmit(&huart2, (uint8_t *)&ch, 1, 0xFFFF);
return ch;
}