最新的STM32_HAL库无法打开和关闭串口TXE中断

发布于 2019-11-28 11:43:10 浏览：2437 订阅该版

因为STM32的各bsp包里的串口驱动一直都没有实现中断发送，前两天看到论坛上关于这个的讨论 [链接](https://www.rt-thread.org/qa/forum.php?mod=viewthread&tid=422730&page=1#pid469913)，就想要试试看。我是在野火429核心板上测试的，调试发现使用STM32_HAL的库函数（宏定义）__HAL_UART_ENABLE_IT(UART_IT_TXE) 和 __HAL_UART_DISABLE_IT(UART_IT_TXE) 并不能打开或关闭 UART_IT_TXE中断。
我先找到了这两个宏定义：
```/** @brief  Enable the specified UART interrupt.
  * @param  __HANDLE__ specifies the UART Handle.
  *         UART Handle selects the USARTx or UARTy peripheral
  *         (USART,UART availability and x,y values depending on device).
  * @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 __HAL_UART_ENABLE_IT(__HANDLE__, __INTERRUPT__)   ((((__INTERRUPT__) >> 28U) == UART_CR1_REG_INDEX)? ((__HANDLE__)->Instance->CR1 |= ((__INTERRUPT__) & UART_IT_MASK)): \
                                                           (((__INTERRUPT__) >> 28U) == UART_CR2_REG_INDEX)? ((__HANDLE__)->Instance->CR2 |= ((__INTERRUPT__) & UART_IT_MASK)): \
                                                           ((__HANDLE__)->Instance->CR3 |= ((__INTERRUPT__) & UART_IT_MASK)))

/** @brief  Disable the specified UART interrupt.
  * @param  __HANDLE__ specifies the UART Handle.
  *         UART Handle selects the USARTx or UARTy peripheral
  *         (USART,UART availability and x,y values depending on device).
  * @param  __INTERRUPT__ specifies the UART interrupt source to disable.
  *          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 __HAL_UART_DISABLE_IT(__HANDLE__, __INTERRUPT__)  ((((__INTERRUPT__) >> 28U) == UART_CR1_REG_INDEX)? ((__HANDLE__)->Instance->CR1 &= ~((__INTERRUPT__) & UART_IT_MASK)): \
                                                           (((__INTERRUPT__) >> 28U) == UART_CR2_REG_INDEX)? ((__HANDLE__)->Instance->CR2 &= ~((__INTERRUPT__) & UART_IT_MASK)): \
                                                           ((__HANDLE__)->Instance->CR3 &= ~ ((__INTERRUPT__) & UART_IT_MASK)))
```时间是复合型三目运算符来实现的，简单的三目运算符我还能理解，但是这里的这个有点太复杂了。
通过查资料可以发现，TXEIE中断开关就在CR1寄存器里，所以我直接将上面的三目运算简化为：

打开中断：
```(&(uart->handle))->Instance->CR1 |= ((UART_FLAG_TXE) & UART_IT_MASK);```
关闭中断：
```(&(uart->handle))->Instance->CR1 &= ~((UART_FLAG_TXE) & UART_IT_MASK);```测试可以实现TXE中断的打开和关闭，也就是说HAL库函数的宏定义里用到的三目运算有问题。那到底错在哪里呢，有哪位能解释一下呢？

还有就是这个宏定义对于有些中断还是可以打开和关闭的，如 
```__HAL_UART_DISABLE_IT(&(uart->handle), UART_IT_RXNE);```因为没有一一测试，暂时只发现TXE中断使能/关闭的问题。

3 个回答

yaomo718 2019-12-12

这家伙很懒，什么也没写！

SXW101320 2019-12-12

这家伙很懒，什么也没写！

您好，我按照之前发的代码的例子，使用串口发送中断。现在串口不能发送。我现在不清楚open时以什么方式打开设备

```

uint8_t ch[8] = {0xff};
serial = rt_device_find("uart3");
rt_device_open(serial,RT_DEVICE_FLAG_INT_TX | RT_DEVICE_FLAG_INT_RX);

rt_device_write(serial, 0, ch, 8);

static rt_err_t scm4_control(struct rt_serial_device *serial, int cmd, void *arg)
{
    struct scm_uart *uart;

RT_ASSERT(serial != RT_NULL);
    uart = rt_container_of(serial, struct scm_uart, serial);

switch (cmd)
    {
		/* disable interrupt */
		case RT_DEVICE_CTRL_CLR_INT:
			/* disable rx irq */
			NVIC_DisableIRQ(uart->irq);
			/* disable interrupt */
			USART_INTConfig(uart->Uazx, USART_INT_RDNE, DISABLE);
			break;
		/* enable interrupt */
		case RT_DEVICE_CTRL_SET_INT:
		   /* enable rx irq */
			NVIC_EnableIRQ(uart->irq);
			/* enable interrupt */
			if(serial->parent.open_flag & RT_DEVICE_FLAG_INT_RX)	//SXW 20191212接收非空中断
			{
				USART_INTConfig(uart->Uazx, USART_INT_RDNE, ENABLE);
			}
			
			if(serial->parent.open_flag & RT_DEVICE_FLAG_INT_TX)	//SXW 20191212发送空中断
			{
				USART_INTConfig(uart->Uazx, USART_INT_TDE, ENABLE);
			}

break;
    }
    return RT_EOK;
}

static int scm4_putc(struct rt_serial_device *serial, char c)
{
    struct scm_uart *uart;
    RT_ASSERT(serial != RT_NULL);

uart = rt_container_of(serial, struct scm_uart, serial);
	
	if(serial->parent.open_flag & RT_DEVICE_FLAG_INT_TX)
	{
		if(USART_GetFlagStatus(uart->Uazx,USART_FLAG_TDE) != RESET)
		{
			USART_ClearFlag(uart->Uazx,USART_FLAG_TDE);
			uart->Uazx->DT = (c & (uint16_t)0x01FF);
		
			return 1;
		}
		else
		{
			return -1;
		}
	}
	else
	{
		USART_ClearFlag(uart->Uazx,USART_FLAG_TRAC);
		uart->Uazx->DT = (c & (uint16_t)0x01FF);
		while (USART_GetFlagStatus(uart->Uazx, USART_FLAG_TRAC) == RESET);
		
		return 1;
	}
}

static void uart_isr(struct rt_serial_device *serial)
{
    struct scm_uart *uart;

RT_ASSERT(serial != RT_NULL);
    uart = rt_container_of(serial, struct scm_uart, serial);

/* UART in mode Receiver -------------------------------------------------*/
    if ((USART_GetFlagStatus(uart->Uazx, USART_FLAG_RDNE) != RESET) &&	//SXW接收中断
            (USART_GetITStatus(uart->Uazx, USART_INT_RDNE) != RESET))
    {
        rt_hw_serial_isr(serial, RT_SERIAL_EVENT_RX_IND);
        /* Clear RXNE interrupt flag */
        USART_ClearITPendingBit(uart->Uazx, USART_INT_RDNE);
    }
	
	else if(USART_GetFlagStatus(uart->Uazx,USART_FLAG_TDE) != RESET)
	{
		if(serial->parent.open_flag & RT_DEVICE_FLAG_INT_TX)
		{
			rt_hw_serial_isr(serial, RT_SERIAL_EVENT_TX_DONE);
			USART_ClearFlag(uart->Uazx,USART_FLAG_TDE);
		}
	}
}
```