Posted on May 25, 2017 at 14:35 Ben,
you must enable RX NOT EMPTY inturrupt on uart, as you suggested:
__HAL_UART_ENABLE_IT(&UartHandle,USART_CR1_RXNEIE);
Hence,
USARTx_IRQHandler()
will be called upon *each* byte reception on the UART.
I suggested you can add your own code in source file stm32f7xx_it.c, inside USARTx_IRQHandler(), between
USER CODE BEGIN USART2_IRQn 1 and
USER CODE END USART2_IRQn 1.
Since USARTx_IRQHandler() will be called upon *each* byte reception on the UART, you know where is the last character received!
The HAL functions know where is the next free array position, since they must store the next received character.
If you read stm32f7xx_hal_usart.c, inside USART_Receive_IT() you can see that the handle husart contains such pointer.
The *last* received character has been stored at (husart->pRxBuffPtr -1).
If your UART handle is named UartHandle, then the last received character is
*(UartHandle->pRxBuffPtr -1)
.
So, you can write something like:
if (*(UartHandle->pRxBuffPtr -1) == '\n')
end_of_line_reached = TRUE;
else
end_of_line_reached = FALSE;
You can learn a lot by reading inside the HAL sources.
Finally, your function USARTx_IRQHandler() seems way too long for an IRQ handler, which is usually executed at a priority level and therefore delays other lower priority IRQ handlers until it is finished.
Good real time coding requires to do as
little as you can inside the IRQ handler, and perform all longer actions which can be delayed (like calling
BSP_LCD_ClearStringLine()
and
BSP_LCD_DisplayStringAtLine()
)outside the IRQ handler, e.g. in the background scheduler.
Cheers,
Mauro
