给串口屏发送波形stm

要给串口屏发送波形，一般需要以下步骤：

1. 准备好要发送的波形数据，可以是数组或者文件等形式。

2. 打开串口并设置波特率、数据位、停止位、校验位等参数。

3. 将波形数据按照协议格式打包，包括帧头、数据长度、数据内容、校验和等。

4. 使用串口发送函数将数据发送到串口。

下面是一个简单的示例代码，可以发送一个正弦波形到串口屏上：

#include <stdio.h>
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include <windows.h>

#define PI 3.14159265358979323846

// 定义串口句柄
HANDLE hCom;

// 打开串口
int openSerialPort(char *portName, int baudrate, int dataBits, char parity, int stopBits)
{
    // 打开串口
    hCom = CreateFile(portName, GENERIC_READ | GENERIC_WRITE, 0, NULL, OPEN_EXISTING, 0, NULL);
    if (hCom == INVALID_HANDLE_VALUE) {
        printf("Failed to open serial port!\n");
        return -1;
    }

    // 配置串口参数
    DCB dcb = {0};
    dcb.DCBlength = sizeof(DCB);
    if (!GetCommState(hCom, &dcb)) {
        printf("Failed to get serial port state!\n");
        CloseHandle(hCom);
        return -1;
    }
    dcb.BaudRate = baudrate;
    dcb.ByteSize = dataBits;
    dcb.Parity = parity;
    dcb.StopBits = stopBits;
    if (!SetCommState(hCom, &dcb)) {
        printf("Failed to set serial port state!\n");
        CloseHandle(hCom);
        return -1;
    }

    // 配置串口超时时间
    COMMTIMEOUTS timeouts = {0};
    timeouts.ReadIntervalTimeout = 50;
    timeouts.ReadTotalTimeoutMultiplier = 10;
    timeouts.ReadTotalTimeoutConstant = 100;
    timeouts.WriteTotalTimeoutMultiplier = 10;
    timeouts.WriteTotalTimeoutConstant = 100;
    if (!SetCommTimeouts(hCom, &timeouts)) {
        printf("Failed to set serial port timeouts!\n");
        CloseHandle(hCom);
        return -1;
    }

    return 0;
}

// 关闭串口
void closeSerialPort()
{
    CloseHandle(hCom);
}

// 发送数据
int sendData(unsigned char *buf, int len)
{
    DWORD dwBytesWritten;
    if (!WriteFile(hCom, buf, len, &dwBytesWritten, NULL)) {
        printf("Failed to send data!\n");
        return -1;
    }
    return dwBytesWritten;
}

// 发送波形数据
int sendWaveform()
{
    // 准备波形数据
    int waveformLength = 256;
    unsigned char waveformData[waveformLength];
    for (int i = 0; i < waveformLength; i++) {
        waveformData[i] = (unsigned char)(127.0 * sin(2 * PI * i / waveformLength) + 128.0);
    }

    // 打包数据并发送
    unsigned char buf[waveformLength + 6];
    buf[0] = 0xA5;  // 帧头
    buf[1] = 0x5A;  // 帧头
    buf[2] = waveformLength;  // 数据长度
    memcpy(buf + 3, waveformData, waveformLength);  // 数据内容
    unsigned char checksum = 0;
    for (int i = 0; i < waveformLength + 3; i++) {
        checksum += buf[i];
    }
    buf[waveformLength + 3] = checksum;  // 校验和
    buf[waveformLength + 4] = 0x0D;  // 结束符
    buf[waveformLength + 5] = 0x0A;  // 结束符

    int ret = sendData(buf, waveformLength + 6);
    return ret;
}

int main()
{
    // 打开串口
    char portName[] = "COM1";
    int baudrate = 9600;
    int dataBits = 8;
    char parity = 'N';
    int stopBits = ONESTOPBIT;
    if (openSerialPort(portName, baudrate, dataBits, parity, stopBits) != 0) {
        return -1;
    }

    // 发送波形数据
    int ret = sendWaveform();
    if (ret < 0) {
        printf("Failed to send waveform data!\n");
    } else {
        printf("Sent %d bytes of waveform data.\n", ret);
    }

    // 关闭串口
    closeSerialPort();

    return 0;
}

注意，上述代码中的协议格式仅供参考，实际情况可能需要根据具体的串口屏协议进行调整。