Usart_interrupt

[julienterrier39]

Posted on August 25, 2015 at 21:34

Hello, I work with a STM32F429ZIT Âµcontroller and I have a set back. I wish find someone who could explain me what's happening in details in this part of the prog:

/** @brief  Enable the specified UART interrupt.

  * @param  __HANDLE__: specifies the UART Handle.

  *         This parameter can be UARTx where x: 1, 2, 3, 4, 5, 6, 7 or 8 to select the USART or

  *         UART peripheral.

  * @param  __INTERRUPT__: specifies the UART interrupt source to enable.

  *          This parameter can be one of the following values:

  *            @arg UART_IT_CTS:  CTS change interrupt

  *            @arg UART_IT_LBD:  LIN Break detection interrupt

  *            @arg UART_IT_TXE:  Transmit Data Register empty interrupt

  *            @arg UART_IT_TC:   Transmission complete interrupt

  *            @arg UART_IT_RXNE: Receive Data register not empty interrupt

  *            @arg UART_IT_IDLE: Idle line detection interrupt

  *            @arg UART_IT_PE:   Parity Error interrupt

  *            @arg UART_IT_ERR:  Error interrupt(Frame error, noise error, overrun error)

  * @retval None

  */

#define UART_IT_MASK  ((uint32_t)0x0000FFFF)

#define __HAL_UART_ENABLE_IT(__HANDLE__, __INTERRUPT__)   ((((__INTERRUPT__) >> 28) == 1)? ((__HANDLE__)->Instance->CR1 |= ((__INTERRUPT__) & UART_IT_MASK)): \

(((__INTERRUPT__) >> 28) == 2)? ((__HANDLE__)->Instance->CR2 |=  ((__INTERRUPT__) & UART_IT_MASK)): \

((__HANDLE__)->Instance->CR3 |= ((__INTERRUPT__) & UART_IT_MASK)))

[Nickname5522_O]

Posted on September 04, 2015 at 12:04

Hi julien.terrier,

As mentioned in the UM1725 HAL_UART_TxCpltCallback is executed in DMA and interrupt modes at transmission end of transfer. And the reference _Weak means that you can add your own code in it. There is more details and examples in section 60.2.3/2.12.3.3 of UM1725. -Shahrzad-

[julienterrier39]

Posted on September 05, 2015 at 23:32

Hi Shahrzad,

Everything is clear now, I found function which call

void HAL_UART_TxCpltCallback(UART_HandleTypeDef *UartHandle)

and I understood how work the Nested Vector Interrupt Controller:

/* Definition for USARTx's NVIC */
#define USARTx_IRQn USART1_IRQn
#define USARTx_IRQHandler USART1_IRQHandler

So when an interrupt comes the µcontroller is locked because the vector suited at the interrupt worked! Then we use this fonction to execute an interrupt:

void HAL_UART_IRQHandler(UART_HandleTypeDef *huart)
{
uint32_t tmp1 = 0, tmp2 = 0;
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_PE);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_PE); 
/* UART parity error interrupt occurred ------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{ 
__HAL_UART_CLEAR_PEFLAG(huart);
huart->ErrorCode |= HAL_UART_ERROR_PE;
}
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_FE);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_ERR);
/* UART frame error interrupt occurred -------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{ 
__HAL_UART_CLEAR_FEFLAG(huart);
huart->ErrorCode |= HAL_UART_ERROR_FE;
}
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_NE);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_ERR);
/* UART noise error interrupt occurred -------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{ 
__HAL_UART_CLEAR_NEFLAG(huart);
huart->ErrorCode |= HAL_UART_ERROR_NE;
}
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_ORE);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_ERR);
/* UART Over-Run interrupt occurred ----------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{ 
__HAL_UART_CLEAR_OREFLAG(huart);
huart->ErrorCode |= HAL_UART_ERROR_ORE;
}
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_RXNE);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_RXNE);
/* UART in mode Receiver ---------------------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{ 
UART_Receive_IT(huart);
}
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_TXE);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_TXE);
/* UART in mode Transmitter ------------------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{
UART_Transmit_IT(huart);
}
tmp1 = __HAL_UART_GET_FLAG(huart, UART_FLAG_TC);
tmp2 = __HAL_UART_GET_IT_SOURCE(huart, UART_IT_TC);
/* UART in mode Transmitter end --------------------------------------------*/
if((tmp1 != RESET) && (tmp2 != RESET))
{
UART_EndTransmit_IT(huart);
}
if(huart->ErrorCode != HAL_UART_ERROR_NONE)
{
/* Set the UART state ready to be able to start again the process */
huart->State = HAL_UART_STATE_READY;
HAL_UART_ErrorCallback(huart);
} 
}

And if we are in UART mode transmitter end we execute this function:

static HAL_StatusTypeDef UART_EndTransmit_IT(UART_HandleTypeDef *huart)
{
/* Disable the UART Transmit Complete Interrupt */ 
__HAL_UART_DISABLE_IT(huart, UART_IT_TC);
/* Check if a receive process is ongoing or not */
if(huart->State == HAL_UART_STATE_BUSY_TX_RX) 
{
huart->State = HAL_UART_STATE_BUSY_RX;
}
else
{
/* Disable the UART Parity Error Interrupt */
__HAL_UART_DISABLE_IT(huart, UART_IT_PE);
/* Disable the UART Error Interrupt: (Frame error, noise error, overrun error) */
__HAL_UART_DISABLE_IT(huart, UART_IT_ERR);
huart->State = HAL_UART_STATE_READY;
}
HAL_UART_TxCpltCallback(huart);
return HAL_OK;
}

To finishHAL_UART_TxCpltCallback(huart); is called! For the attribut _weak I found several information therefore now I understood how to use it! thank you