UART_Polling模式代码

主函数

usart_polling.c

int main(void)
{
    uint8_t ch;
    usart_config_t config;                              // 配置波特率、帧格式、上升下降沿、奇偶校验、停止位等

    /* Security code to allow debug access */
    SYSCON->CODESECURITYPROT = 0x87654320;

    /* attach clock for USART(debug console) */
    CLOCK_AttachClk(BOARD_DEBUG_UART_CLK_ATTACH);

    /* reset FLEXCOMM for USART */
    RESET_PeripheralReset(kFC0_RST_SHIFT_RSTn);

    BOARD_BootClockRUN();
    BOARD_InitDebugConsole();
    BOARD_InitPins();
    /*
     * config.baudRate_Bps = 115200U;
     * config.parityMode = kUSART_ParityDisabled;
     * config.stopBitCount = kUSART_OneStopBit;
     * config.loopback = false;
     * config.enableTx = false;
     * config.enableRx = false;
     */
    USART_GetDefaultConfig(&config);                    // 使用默认配置，传入config的引用
    config.baudRate_Bps = BOARD_DEBUG_UART_BAUDRATE;    // 客制化usart配置
    config.enableTx     = true;
    config.enableRx     = true;

    USART_Init(DEMO_USART, &config, DEMO_USART_CLK_FREQ);           // 使用config和外部时钟初始化USART实例，其中外部时钟只在设置波特率时使用

    USART_WriteBlocking(DEMO_USART, txbuff, sizeof(txbuff) - 1);    // 将数组中的值写入

    while (1)
    {
        PRINTF("READ:\n\r");
        USART_ReadBlocking(DEMO_USART, &ch, 1);                     // 数据逐个从FIFORD读入ch，这里只读入一位
        PRINTF("\n\rWRITE:\n\r");
        USART_WriteBlocking(DEMO_USART, &ch, 1);                    // 数据逐个从ch写入FIFOWR，这里只读入一位，等待TX进入IDLE模式结束
        PRINTF("\n\r");
    }
}

只接收一个char

实验结果：

接收字符串

原始代码修改为接收一个定长5的array，代码：

int main(void)
{
    uint8_t array[6];
    usart_config_t config;

    /* Security code to allow debug access */
    SYSCON->CODESECURITYPROT = 0x87654320;

    /* attach clock for USART(debug console) */
    CLOCK_AttachClk(BOARD_DEBUG_UART_CLK_ATTACH);

    /* reset FLEXCOMM for USART */
    RESET_PeripheralReset(kFC0_RST_SHIFT_RSTn);

    BOARD_BootClockRUN();
    BOARD_InitDebugConsole();
    BOARD_InitPins();
    /*
     * config.baudRate_Bps = 115200U;
     * config.parityMode = kUSART_ParityDisabled;
     * config.stopBitCount = kUSART_OneStopBit;
     * config.loopback = false;
     * config.enableTx = false;
     * config.enableRx = false;
     */
    USART_GetDefaultConfig(&config);
    config.baudRate_Bps = BOARD_DEBUG_UART_BAUDRATE;
    config.enableTx     = true;
    config.enableRx     = true;

    USART_Init(DEMO_USART, &config, DEMO_USART_CLK_FREQ);

    USART_WriteBlocking(DEMO_USART, txbuff, sizeof(txbuff) - 1);

    while (1)
    {
        PRINTF("READ:\n\r");
        USART_ReadBlocking(DEMO_USART, &array, sizeof(array) - 1);
        PRINTF("\n\rWRITE:\n\r");
        USART_WriteBlocking(DEMO_USART, &array, sizeof(array) - 1);
        PRINTF("\n\r");
    }
}

实验结果：