[嵌入式]STM32F4Discovery HAL之UART通信

前言

STM32F4Discovery开发板，由于PA9复用成了USB OTG的vbus，线路上有电容，导致不能正常用作UART。
UART1不仅仅适用PA9和PA10，也可以使用PB6，PB7
STM32F4Discovery USART1 PA9不能使用.

环境

硬件

STM32F4Discovery

软件

STM32CubeMX V6.2.1

配置

配置UART1_TX跟UART1_RX口为PB6，PB7

代码

函数说明

发送函数：HAL_UART_Transmit(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)
接收函数：HAL_UART_Receive(UART_HandleTypeDef *huart, uint8_t *pData, uint16_t Size, uint32_t Timeout)

代码实例

if (HAL_UART_Receive(&huart1, rx_buff, sizeof(rx_buff),1000) == HAL_OK)
    {
        switch(rx_buff[0]){
            case 0xA1:
                set_voltage(DAC_CHANNEL_1, rx_buff[1]<<8 | rx_buff[2]);
                get_voltage(DAC_CHANNEL_1);
                HAL_UART_Transmit(&huart1, (uint8_t *)tx_buff, 2, 100);
                break;
            case 0xA2:
                set_voltage(DAC_CHANNEL_2, rx_buff[1]<<8 | rx_buff[2]);
                get_voltage(DAC_CHANNEL_2);
                HAL_UART_Transmit(&huart1, (uint8_t *)tx_buff, 2, 100);
                break;
            case 0xB1:
                get_voltage(DAC_CHANNEL_1);
                HAL_UART_Transmit(&huart1, (uint8_t *)tx_buff, 2, 100);
                break;
            case 0xB2:
                get_voltage(DAC_CHANNEL_2);
                HAL_UART_Transmit(&huart1, (uint8_t *)tx_buff, 2, 100);
                break;
            default:
                HAL_UART_Transmit(&huart1, rx_buff, sizeof(rx_buff),100);
                
                break;
        }
    }

输出结果示例