本帖最后由 liuqian 于 2019-8-13 08:54 编辑
hal库中的源码
/**
* @brief Sets or clears the selected data port bit.
*
* @note This function uses GPIOx_BSRR register to allow atomic read/modify
* accesses. In this way, there is no risk of an IRQ occurring between
* the read and the modify access.
*
* @param GPIOx: where x can be (A..G depending on device used) to select the GPIO peripheral
* @param GPIO_Pin: specifies the port bit to be written.
* This parameter can be one of GPIO_PIN_x where x can be (0..15).
* @param PinState: specifies the value to be written to the selected bit.
* This parameter can be one of the GPIO_PinState enum values:
* @arg GPIO_PIN_RESET: to clear the port pin
* @arg GPIO_PIN_SET: to set the port pin
* @retval None
*/
void HAL_GPIO_WritePin(GPIO_TypeDef *GPIOx, uint16_t GPIO_Pin, GPIO_PinState PinState)
{
/* Check the parameters */
assert_param(IS_GPIO_PIN(GPIO_Pin));
assert_param(IS_GPIO_PIN_ACTION(PinState));
if (PinState != GPIO_PIN_RESET)
{
GPIOx->BSRR = GPIO_Pin;
}
else
{
GPIOx->BSRR = (uint32_t)GPIO_Pin << 16U; // 为什么不直接用GPIOx->BRR = GPIO_Pin,非要画蛇添足的去移位再写BSRR
}
}
/**
* @brief Toggles the specified GPIO pin
* @param GPIOx: where x can be (A..G depending on device used) to select the GPIO peripheral
* @param GPIO_Pin: Specifies the pins to be toggled.
* @retval None
*/
void HAL_GPIO_TogglePin(GPIO_TypeDef *GPIOx, uint16_t GPIO_Pin)
{
/* Check the parameters */
assert_param(IS_GPIO_PIN(GPIO_Pin));
GPIOx->ODR ^= GPIO_Pin; // 不是原子操作了,有可能影响到其他的位,应该用BSRR和BRR才对呀
}
友情提示: 此问题已得到解决,问题已经关闭,关闭后问题禁止继续编辑,回答。
/**
* @brief Sets or clears the selected data port bit.
*
* @note This function uses GPIOx_BSRR register to allow atomic read/modify
* accesses. In this way, there is no risk of an IRQ occurring between
* the read and the modify access.
*
* @param GPIOx where x can be (A..I) to select the GPIO peripheral for all STM32F2XX devices
* @param GPIO_Pin specifies the port bit to be written.
* This parameter can be one of GPIO_PIN_x where x can be (0..15).
* @param PinState specifies the value to be written to the selected bit.
* This parameter can be one of the GPIO_PinState enum values:
* @arg GPIO_PIN_RESET: to clear the port pin
* @arg GPIO_PIN_SET: to set the port pin
* @retval None
*/
void HAL_GPIO_WritePin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin, GPIO_PinState PinState)
{
/* Check the parameters */
assert_param(IS_GPIO_PIN(GPIO_Pin));
assert_param(IS_GPIO_PIN_ACTION(PinState));
if(PinState != GPIO_PIN_RESET)
{
GPIOx->BSRR = GPIO_Pin;
}
else
{
GPIOx->BSRR = (uint32_t)GPIO_Pin << 16U;
}
}
/**
* @brief Toggles the specified GPIO pins.
* @param GPIOx where x can be (A..I) to select the GPIO peripheral.
* @param GPIO_Pin Specifies the pins to be toggled.
* @retval None
*/
void HAL_GPIO_TogglePin(GPIO_TypeDef* GPIOx, uint16_t GPIO_Pin)
{
/* Check the parameters */
assert_param(IS_GPIO_PIN(GPIO_Pin));
if ((GPIOx->ODR & GPIO_Pin) != 0X00u)
{
GPIOx->BSRR = (uint32_t)GPIO_Pin << GPIO_NUMBER;
}
else
{
GPIOx->BSRR = (uint32_t)GPIO_Pin;
}
}
一周热门 更多>