Hi all,
I try to install a synchronous USART communication between 2 x STM32H743, one is the (transmitting only ) Master the other is the (receiving only) Slave. When transferring data via Polling everything seems to work well.
But when using HAL_USART_Receive_IT the USART produces an UDR Underrun error in the Slave USART. As this is a tranmission related error I disabled this error case in the HAL. But then I get an Overrun error interrupt after the first byte in the block.
Did anyone use the USART in synchronous mode as a Slave with Interrupt reception. (Or DMA - which I did not try yet)?
Init Code:
void MX_USART3_Init(void)
{
husart3.Instance = USART3;
husart3.Init.BaudRate = 1000000;
husart3.Init.WordLength = USART_WORDLENGTH_8B;
husart3.Init.StopBits = USART_STOPBITS_1;
husart3.Init.Parity = USART_PARITY_NONE;
husart3.Init.Mode = USART_MODE_RX;
husart3.Init.CLKPolarity = USART_POLARITY_HIGH;
husart3.Init.CLKPhase = USART_PHASE_2EDGE;
husart3.Init.CLKLastBit = USART_LASTBIT_ENABLE;
husart3.Init.Prescaler = USART_PRESCALER_DIV1;
husart3.Init.SlaveMode = USART_SLAVEMODE_ENABLE;
husart3.Init.FIFOMode = USART_FIFOMODE_ENABLE; // or DISABLE - doesn't change behaviour
husart3.Init.TXFIFOThreshold = USART_TXFIFO_THRESHOLD_1_8;
husart3.Init.RXFIFOThreshold = USART_RXFIFO_THRESHOLD_1_8;
if (HAL_USART_Init(&husart3) != HAL_OK)
{
Error_Handler();
}
}
