报个rt_thread studio配置stm32L412的串口bug及其解决

发布于 2022-01-22 20:50:03 浏览：778 订阅该版

我用一块ST官方的Nucleo-32L412KB开发板(MB1180)测试rt-thread studio, MCU型号是stm32L412KBUx 遇到的问题是finsh输出正常, 但是对于串口的输入没有响应, 串口中断也没有执行.

后来发现问题在于: 这块demo板的uart2对应的TX pin是PA2, RX Pin 是PA15, 而rtt studio生成代码drv_uart.c的stm32_gpio_configure()函数, 对于IO Pin的配置是这样的
```
#if defined(SOC_SERIES_STM32F2) || defined(SOC_SERIES_STM32F4) || \
    defined(SOC_SERIES_STM32F7) || defined(SOC_SERIES_STM32G4) || \
    defined(SOC_SERIES_STM32L1) || defined(SOC_SERIES_STM32L4)
#define GPIO_AF7   ((uint8_t)0x07)
#define GPIO_AF8   ((uint8_t)0x08)

/* uart1-3 -> AF7, uart4-8 -> AF8 */
    if (uart_num <= 3)
    {
        GPIO_InitStruct.Alternate = GPIO_AF7;
    }
    else
    {
        GPIO_InitStruct.Alternate = GPIO_AF8;
    }
#endif
    HAL_GPIO_Init(tx_port, &GPIO_InitStruct);

/* rx pin initialize */
    GPIO_InitStruct.Pin = rx_pin;
    HAL_GPIO_Init(rx_port, &GPIO_InitStruct);
```
而这块L412当RX PIN配置成PA15时, 所对应的Alternate不是GPIO_AF7, 而是GPIO_AF3, 因此需要修改成
```
#if defined(SOC_SERIES_STM32F2) || defined(SOC_SERIES_STM32F4) || \
    defined(SOC_SERIES_STM32F7) || defined(SOC_SERIES_STM32G4) || \
    defined(SOC_SERIES_STM32L1) || defined(SOC_SERIES_STM32L4)
#define GPIO_AF7   ((uint8_t)0x07)
#define GPIO_AF8   ((uint8_t)0x08)
#define GPIO_AF3   ((uint8_t)0x03)

/* rx pin initialize */
    GPIO_InitStruct.Pin = rx_pin;
    GPIO_InitStruct.Alternate = GPIO_AF3;            // modified!
    HAL_GPIO_Init(rx_port, &GPIO_InitStruct);
```
则问题解决.