c++ windows串口传输数据

用虚拟串口软件 测试

//////////////////////////////////////SerialPort.h///////////////////////////////////////////////

#include "SerialPort.h"

HANDLE OpenSerialPort(string & strPort, ULONG ulBaudrate)
{
    HANDLE hSerial;
    hSerial = CreateFile((strPort.c_str()),
	GENERIC_READ | GENERIC_WRITE,
	NULL,
	NULL,
	OPEN_EXISTING,
	NULL,
	NULL);
	
if (hSerial == INVALID_HANDLE_VALUE)//Open serial port failed.
{
	return hSerial;
}

//Config serial port
DCB PortDCB;
PortDCB.DCBlength = sizeof(DCB);

// Get the default serial parameter.
GetCommState(hSerial, &PortDCB);
PortDCB.BaudRate = ulBaudrate; 		// baudrate
PortDCB.ByteSize = 8; 				// Number of bits/byte, 4-8 
PortDCB.Parity = NOPARITY;
PortDCB.StopBits = ONESTOPBIT;

if (!SetCommState(hSerial, &PortDCB))
{
	//config the serial port failed.
	CloseHandle(hSerial);
	return (INVALID_HANDLE_VALUE);
}

//Config the serial port timeout property.
COMMTIMEOUTS CommTimeouts;
GetCommTimeouts(hSerial, &CommTimeouts);		//Get the serial port default timeout.
CommTimeouts.ReadIntervalTimeout = MAXDWORD;
CommTimeouts.ReadTotalTimeoutMultiplier = 10;
CommTimeouts.ReadTotalTimeoutConstant = 10;
CommTimeouts.WriteTotalTimeoutMultiplier = 50;
CommTimeouts.WriteTotalTimeoutConstant = 100;

if (!SetCommTimeouts(hSerial, &CommTimeouts))
{
	//config the serial port timeout failed;
	CloseHandle(hSerial);
	return (INVALID_HANDLE_VALUE);
}
	return (hSerial);
};

void CloseSerialPort(HANDLE hSerial)	
{
	CloseHandle(hSerial);
};

bool WriteSerial(char* btData, ULONG ulSize, HANDLE hSerial)
{
	DWORD dwNumBytes, dwRet;
	dwRet = WriteFile(hSerial, //Handle
	btData, //Data buffer
	ulSize, //Buffer size
	&dwNumBytes, //written bytes
	NULL); //don't support

	return (dwRet != 0);
};

bool ReadSerial(BYTE *btData, ULONG *ulSize, HANDLE hSerial)
{
	//SetCommMask (hSerial, EV_RXCHAR);
	ULONG ulRdSize = 0;
	BYTE Byte;
	DWORD dwBytes;
	bool blRd = false;
	DWORD dwMask = EV_RXCHAR;
	//WaitCommEvent(hSerial,&dwMask,NULL);
	SetCommMask(hSerial, EV_RXCHAR);
	while (ReadFile(hSerial, &Byte, 1, &dwBytes, 0) != 0) 
	{
	if (dwBytes>0) 
	{
		btData[ulRdSize++] = Byte;
		
		if (ulRdSize == *ulSize) 
		{
			blRd = true;
			break;
		}
	}

	else 
	{	
		blRd = true;
		break;
	}
}

	*ulSize = ulRdSize;
	return (blRd);
};

//===========================SerialPort.H的开始=========================

#pragma once
#include <windows.h>
#include <string>

using namespace std;
HANDLE OpenSerialPort(string & strPort, ULONG ulBaudrate);
void CloseSerialPort(HANDLE hSerial);
bool WriteSerial(char* btData, ULONG ulSize, HANDLE hSerial);
bool ReadSerial(BYTE *btData, ULONG *ulSize, HANDLE hSerial);

//===========================SerialPort.H的结束=========================

///////////////////////////////main.cpp////////////////////////////////////////

//使用代码示例: 
#include "SerialPort.h"
#include <iostream>
using namespace std;

HANDLE hSerialPort;

int main()
{
	string portname = "COM4:";
	string buff = "HELLO!";
	char c[20];
	strcpy_s(c, buff.c_str());

	hSerialPort = OpenSerialPort( portname, 9600);//Open serial port com1

	if (hSerialPort != INVALID_HANDLE_VALUE)
	{
		if (!WriteSerial(c, 7, hSerialPort))//Send data hello to com1
		
		//MessageBox(0, "ERROR", "ERROR", MB_ICONWARNING);//show error message
		printf("ERROR!!");
		//CloseSerialPort(hSerialPort);
	}
	system("pause");
}