EC20 C语言单片机代码

EC20模块的C语言单片机代码主要涉及到串口通信和AT指令的发送与接收。下面以STM32为例，提供一个简单的EC20 C语言单片机代码示例：

#include "stm32f4xx.h"
#include <string.h>

#define EC20_USART USART2

void USART2_Init(void) {
    GPIO_InitTypeDef GPIO_InitStruct;
    USART_InitTypeDef USART_InitStruct;
    NVIC_InitTypeDef NVIC_InitStruct;

    // 使能时钟
    RCC_AHB1PeriphClockCmd(RCC_AHB1Periph_GPIOA, ENABLE);
    RCC_APB1PeriphClockCmd(RCC_APB1Periph_USART2, ENABLE);

    // 配置GPIO
    GPIO_InitStruct.GPIO_Mode = GPIO_Mode_AF;
    GPIO_InitStruct.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_3;
    GPIO_InitStruct.GPIO_Speed = GPIO_Speed_50MHz;
    GPIO_InitStruct.GPIO_OType = GPIO_OType_PP;
    GPIO_InitStruct.GPIO_PuPd = GPIO_PuPd_UP;
    GPIO_Init(GPIOA, &GPIO_InitStruct);

    GPIO_PinAFConfig(GPIOA, GPIO_PinSource2, GPIO_AF_USART2);
    GPIO_PinAFConfig(GPIOA, GPIO_PinSource3, GPIO_AF_USART2);

    // 配置USART
    USART_InitStruct.USART_BaudRate = 115200;
    USART_InitStruct.USART_WordLength = USART_WordLength_8b;
    USART_InitStruct.USART_StopBits = USART_StopBits_1;
    USART_InitStruct.USART_Parity = USART_Parity_No;
    USART_InitStruct.USART_HardwareFlowControl = USART_HardwareFlowControl_None;
    USART_InitStruct.USART_Mode = USART_Mode_Rx | USART_Mode_Tx;
    USART_Init(EC20_USART, &USART_InitStruct);

    // 配置中断
    NVIC_InitStruct.NVIC_IRQChannel = USART2_IRQn;
    NVIC_InitStruct.NVIC_IRQChannelPreemptionPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelSubPriority = 0;
    NVIC_InitStruct.NVIC_IRQChannelCmd = ENABLE;
    NVIC_Init(&NVIC_InitStruct);

    USART_ITConfig(EC20_USART, USART_IT_RXNE, ENABLE);

    // 启动USART
    USART_Cmd(EC20_USART, ENABLE);
}

void USART2_IRQHandler(void) {
    static uint8_t buf[1024];
    static int buf_len = 0;

    if (USART_GetITStatus(EC20_USART, USART_IT_RXNE) != RESET) {
        uint8_t ch = USART_ReceiveData(EC20_USART);

        if (buf_len < sizeof(buf) - 1) {
            buf[buf_len++] = ch;
        }
    }
}

void EC20_SendATCommand(const char* cmd) {
    int cmd_len = strlen(cmd);

    for (int i = 0; i < cmd_len; i++) {
        USART_SendData(EC20_USART, cmd[i]);
        while (USART_GetFlagStatus(EC20_USART, USART_FLAG_TXE) == RESET);
    }

    USART_SendData(EC20_USART, '\r');
    while (USART_GetFlagStatus(EC20_USART, USART_FLAG_TXE) == RESET);

    USART_SendData(EC20_USART, '\n');
    while (USART_GetFlagStatus(EC20_USART, USART_FLAG_TXE) == RESET);
}

void EC20_ReceiveResponse(char* buf, int buf_size) {
    int buf_len = 0;

    while (1) {
        if (USART_GetFlagStatus(EC20_USART, USART_FLAG_RXNE) != RESET) {
            char ch = USART_ReceiveData(EC20_USART);

            if (ch == '\r' || ch == '\n') {
                buf[buf_len] = '\0';
                break;
            }
            else if (buf_len < buf_size - 1) {
                buf[buf_len++] = ch;
            }
        }
    }
}

int main(void) {
    char buf[1024];

    USART2_Init();

    // 发送AT指令
    EC20_SendATCommand("AT");

    // 读取响应信息
    EC20_ReceiveResponse(buf, sizeof(buf));
    printf("%s\n", buf);

    while (1);

    return 0;
}

这段代码通过STM32的USART2模块与EC20模块进行串口通信，并实现了发送AT指令和接收响应信息的功能。你可以根据自己的需求修改代码，实现更加复杂的功能。