This is the original code for receiving/sending the data (without disabling the TX):
/**
* @brief This function handles USART1 global interrupt / USART1 wake-up interrupt through EXTI line 25.
*/
void USART1_IRQHandler(void)
{
/* USER CODE BEGIN USART1_IRQn 0 */
//check if RXNE interrupt
if(USART1->ISR & USART_ISR_RXNE) //if RX is not empty
{
// Reset timer 15
TIM15->CNT = 0;
// Check if first byte
if(!USART1_receiving)
{
USART1_receiving = 1; // Receiving data
usartReceiveMessageLength = 0; // Reset message length
TIM15->CR1 |= (TIM_CR1_CEN); // Enable timer 15
}
//fetch the data received
USART1_ReceiveBuffer[usartReceiveBufferPointer++] = USART1->RDR;
usartReceiveMessageLength++; // Increment message length
// Reset buffer pointer if overflow
if(usartReceiveBufferPointer >= usartReceiveBufferLength)
usartReceiveBufferPointer = 0;
}
//check if TXE interrupt
if(USART1->ISR & USART_ISR_TXE) //if TX is empty
{
// Check if first byte
if(!USART1_transmitting)
{
USART1_transmitting = 1; // Transmitting data
USART1_transmitDataPointer = 0; // Reset transmit pointer
}
// Transmit RS422 buffer
if(USART1_transmitDataPointer < USART1_transmitDataLength)
USART1->TDR = COM_TransmitBuffer[USART1_transmitDataPointer++];
else
__HAL_UART_DISABLE_IT(&huart1, UART_IT_TXE);
}
// Check if TC interrupt
if(USART1->ISR & USART_ISR_TC)
{
USART1_transmitting = 0; // Done transmitting data
__HAL_UART_DISABLE_IT(&huart1, UART_IT_TC); // Disable flag
USART1->CR1 &= ~USART_CR1_TE; // Disable transmitter
USART1->ICR |= USART_ICR_TCCF; // Reset flag
}
/* USER CODE END USART1_IRQn 0 */
HAL_UART_IRQHandler(&huart1);
/* USER CODE BEGIN USART1_IRQn 1 */
/* USER CODE END USART1_IRQn 1 */
}This is the code to start the transmission:
// Start transmission
if(global_Configuration.responseMessageEnable)
{
__HAL_UART_ENABLE_IT(&huart1, UART_IT_TXE);
__HAL_UART_ENABLE_IT(&huart1, UART_IT_TC);
USART1->CR1 |= USART_CR1_TE;
}When I send a command from the terminal I get the response back. But there are \0 bytes represented by '.' in the terminal.
That's not intended to be there. See the picture below:
When I comment the line:
USART1->CR1 &= ~USART_CR1_TE; // Disable transmitter
The dot is not appearing but the commands response is not working find as you can see from the picture:
I have looked at the content of COM_TransmitBuffer with live expressions and it shows the right content and not the mixed up. So, that's not the problem. And the \0 are not part of COM_TransmitBuffer.
