New UART

1. UART理论

推荐阅读：第九章 UART - 小李 的知识库

Hi3861引脚及复用表：

Pins	Group	默认功能	复用功能
1	IO10	SPI_SCK	I2C0_SDA/UART2_CTS_N/SDIO_D3/SPI0_CK/PWM1_OUT/I2S0_TX
2	IO12	SPI_NSS	UART2_RXD/SDIO_CLK/SPI0_CSN/PWM3_OUT/RF_RX_EN_EXT/I2S0_BCLK
3	NC	-	-
4	IO14	GPIO	SSI_CLK/UART0_RXD/UART2_CTS_N/SDIO_D1/PWM5_OUT/I2C0_SCL
5	IO13	ADC	SSI_DATA/UART0_TXD/UART2_RTS_N/SDIO_D0/PWM4_OUT/I2C0_SDA/I2S0_WS
6	IO02	DAC	UART1_RTS_N/SPI1_TXD/JTAG_TRSTN/PWM2_OUT/SSI_CLK
7	IO07	GPIO	UART1_CTS_N/SPI0_RXD/PWM0_OUT/I2S0_BCLK
8	IO08	GPIO	UART1_RTS_N/SPI0_TXD/PWM1_OUT/I2S0_WS/WLAN_ACTIVE
9	IO01	IIC_SCL	UART1_RXD/SPI1_RXD/JTAG_TCK/PWM4_OUT/I2C1_SCL/
10	IO00	IIC_SDA	UART1_TXD/SPI1_CK/JTAG_TDO/PWM3_OUT/I2C1_SDA
11	IO03	GPIO	UART0_TXD/UART1_CTS_N/SPI1_CSN/JTAG_TDI/PWM5_OUT/I2C1_SDA/SSI_DATA
12	IO05	UART_RX	UART1_RXD/SPI0_CSN/PWM2_OUT/I2S0_MCLK
13	IO06	UART_TX	UART1_TXD/SPI0_CK/PWM3_OUT/I2S0_TX
14	IO04	GPIO	UART0_RXD/JTAG_TMS/PWM1_OUT/I2C1_SCL
15	IO09	SPI_MOSI	I2C0_SCL/UART2_RTS_N/SDIO_D2/SPI0_TXD/PWM0_OUT/I2S0_MCLK
16	IO11	SPI_MISO	UART2_TXD/SDIO_CMD/SPI0_RXD/PWM2_OUT/RF_TX_EN_EXT/I2S0_RX

2. UART简单收发

C

#include <stdio.h>
#include "ohos_init.h"
#include "iot_gpio.h"
#include "iot_uart.h"
#include "iot_errno.h"
#include "hi_io.h"
#include "cmsis_os2.h"

/**
 * uart_demo/uart_demo.c
 * 串口接收信息，并将接收的信息发送回去
 */

#define UART_ID        1
#define UART_TX_PIN    6
#define UART_RX_PIN    5

static void Uart1Init(void)
{
    /* 复用UART1到GPIO5、GPIO6 */
    IoTGpioInit(UART_TX_PIN);
    IoTGpioInit(UART_RX_PIN);
    hi_io_set_func(UART_TX_PIN, HI_IO_FUNC_GPIO_6_UART1_TXD);
    hi_io_set_func(UART_RX_PIN, HI_IO_FUNC_GPIO_5_UART1_RXD);
    /* 配置UART1的属性 */
    IotUartAttribute uartAttr = {
        // 波特率
        .baudRate = 9600,
        // 数据位长度
        .dataBits = IOT_UART_DATA_BIT_8,
        // 停止位长度
        .stopBits = IOT_UART_STOP_BIT_1,
        // 奇偶校验
        .parity = IOT_UART_PARITY_NONE,
        // 发送且接收
        .rxBlock = IOT_UART_BLOCK_STATE_BLOCK,
        .txBlock = IOT_UART_BLOCK_STATE_BLOCK,
        .pad = 0,
    };
    if (IoTUartInit(UART_ID, &uartAttr) != IOT_SUCCESS) {
        printf("[ERROR] UART INIT ERR.\r\n");
    }
}

static void UartTask(void* arg)
{
    /* 初始化串口 */
    Uart1Init();

    uint8_t data[64] = {0};
    while (1) 
    {
        if (IoTUartRead(UART_ID, data, sizeof(data)) < 0) {
            printf("[ERROR] IoTUartRead ERR.\r\n");
        } else {
            printf("[INFO] IoTUartRead RTT.\r\n");
        }
        osDelay(200);
        if (IoTUartWrite(UART_ID, data, 1) < 0) {
            printf("[ERROR] IoTUartWrite ERR.\r\n");
        } else {
            printf("[INFO] IoTUartWrite RTT.\r\n");
        }
        osDelay(200);
    }
}

/* 入口函数 */
static void UartEntry(void)
{
     osThreadAttr_t attr = {
        .name = "UartTask",
        .stack_size = 1024,
        .priority = osPriorityNormal
    };
    if (osThreadNew(UartTask, NULL, &attr) == NULL) {
        printf("[ERROR] Thread Create Faild.\r\n");
    } else {
        printf("[INFO] Thread Create RT.\r\n");
    }
}

SYS_RUN(UartEntry);

模块编译脚本

Text Only

static_library("uart_demo") {
    sources = [
        "uart_demo.c"
    ]
    include_dirs = [
        # include "ohos_init.h"
        "//utils/native/lite/include",
        # include CMSIS-RTOS API V2 for OpenHarmony1.0+
        "//kernel/liteos_m/kal/cmsis",
        # include IoT硬件设备操作接口 for OpenHarmony1.0+：
        "//base/iot_hardware/peripheral/interfaces/kits",
    ]
}

APP编译脚本

Text Only

3import("//build/lite/config/component/lite_component.gni")

lite_component("app") {
    features = [
        "gn_practice/application:gn_app",
        "gn_practice/driver:gn_driver",
        "gn_practice/library:gn_library",
        "kv_store_demo:kv_store_demo",
        "file_demo:file_demo",
        "thread_demo:thread_demo",
        "timer_demo:timer_demo",
        "mutex_demo:mutex_demo",
        # GPIO模块
        "gpio_demo:gpio_demo",
        # ADC模块
        "adc_demo:adc_demo",
        # OLED模块
        "oled_demo:oled_demo",
        # UART模块
        "uart_demo:uart_demo"
    ]
}

3. 发送复杂信息

使用sprintf或snprintf函数将字符、数字封装成一段字符串。

C

static void UartTask(void* arg)
{
    /* 初始化串口 */
    Uart1Init();
    int value = 1;
    unsigned char buffer[64] = {0};
    snprintf(buffer, sizeof(buffer),"[INFO] AT+LOCK=%d\r\n", value);
    while (1) 
    {
        if (IoTUartWrite(UART_ID, buffer, strlen(buffer)) < 0) {
            printf("[ERROR] IoTUartWrite ERR.\r\n");
        } else {
            printf("[INFO] IoTUartWrite RTT.\r\n");
        }
        osDelay(100);
    }
}