Hi All,
I'm after a little bit of advice on how to use the uart interrupts. I would like to implement an interrupt driven uart receiver which takes a single byte at a time and stuffs it into a buffer. When a terminating char is received, a flag is raised and the data can be read.
I have the uart (lpuart) working in polling mode (both receive and transmit) using the HAL commands.
I have implemented this kind of system successfully on other controllers, but am struggling a bit with this one (stm32l476).
In the past, I would create an interrupt handler, clear the rx receive flag, enable the rx interrupt then enable the global interrupt. As a char is received, I would stuff it into a buffer, clear the receive flag and wait for the next char and so on.
I have let STMCubeMX create the interrupt handler template for me and set up the NVIC. However, I do not seem to be getting an interrupt. The NVIC_init has a HAL_NVIC_EnableIRQ(LPUART1_IRQn) in it - do I need to do anything else to enable the interrupts?
I have put together a very simple bit of code in main to flag up if a uart interrupt has been received:-
while (1)
{
if(LPUART1_RX_DATAREADY == 1)
{
HAL_UART_Transmit(&hlpuart1, (uint8_t*)"\r\nGotSomething", 14, 1000);
LPUART1_RX_DATAREADY = 0;
}
/* USER CODE END WHILE */
/* USER CODE BEGIN 3 */
}
/* USER CODE END 3 */
}
LPUART interrupt handler:-
void LPUART1_IRQHandler(void)
{
/* USER CODE BEGIN LPUART1_IRQn 0 */
if(__HAL_UART_GET_IT(&hlpuart1, UART_IT_RXNE) != RESET)
{
LPUART1_RX_DATAREADY = 1;
LPUART1_RX_BUFFER[LPUART1_RX_P] = (uint8_t)(hlpuart1.Instance->RDR & 0x00FF); // read receive reg to clear interrupt.
}
/* USER CODE END LPUART1_IRQn 0 */
HAL_UART_IRQHandler(&hlpuart1);
/* USER CODE BEGIN LPUART1_IRQn 1 */
/* USER CODE END LPUART1_IRQn 1 */
}
What other steps should I be taking? I have found a few examples on google with respect to the HAL_receiveIT library command, but this would be useless in this case as I do not know the length of the receive data in advance + the time out will be dependant on how quick someone can type.
Any constructive advice/pointers would be gratefully received.
Thanks
Peter
