Posted on March 19, 2018 at 20:15Looks like I found a small bug in STM32 CubeMX code generation. It can be reproduced this way:
1. Create new project for STM32F091RB.
2. Enable USART5 with Asynchronous mode and Hardware Flow Control (RS485) on.
3. In Project Settings select Toolchain/IDE = SW4STM32 (probably irrelevant).
4. Generate the code.
As result in the stm32f0xx_hal_msp.c file we have:
void HAL_UART_MspInit(UART_HandleTypeDef* huart)
{
GPIO_InitTypeDef GPIO_InitStruct;
if(huart->Instance==USART5)
{
GPIO_InitStruct.Pin = GPIO_PIN_12;
...
GPIO_InitStruct.Alternate = GPIO_AF2_USART5;
HAL_GPIO_Init(GPIOC, &GPIO_InitStruct);
...
GPIO_InitStruct.Pin = GPIO_PIN_2;
...
GPIO_InitStruct.Alternate = GPIO_AF2_USART5;
HAL_GPIO_Init(GPIOD, &GPIO_InitStruct);
GPIO_InitStruct.Pin = GPIO_PIN_5;
GPIO_InitStruct.Mode = GPIO_MODE_AF_PP;
GPIO_InitStruct.Pull = GPIO_NOPULL;
GPIO_InitStruct.Speed = GPIO_SPEED_FREQ_HIGH; /* [1] */
HAL_GPIO_Init(GPIOB, &GPIO_InitStruct);
}
}
The initialization of
GPIO_InitStruct.
Alternate field for PB5 is missing after the line marked by /* [1] */. The missing line should be:
GPIO_InitStruct.Alternate = GPIO_AF4_USART5;
Otherwise the previous value for PD2 pin is used (
GPIO_AF2_USART5
) and the UART5_DE pin doesn't work.
