zhipuzi_pos_windows/zhipuzi_pos_windows/helper/CSerialPort.cpp

#include "../pch/pch.h"
#include "CSerialPort.h"

CSerialPort::CSerialPort(
    const std::wstring portNum,
    DWORD baudRate /* = 9600 */,
    BYTE byteSize /* = 8 */,
    BYTE parityBit /* = NOPARITY */,
    BYTE stopBit /* = ONESTOPBIT */
) : m_portNum(portNum),
    m_dwBaudRate(baudRate),
    m_byteSize(byteSize),
    m_parityBit(parityBit),
    m_stopBit(stopBit),
    m_bOpen(false)
{

}

CSerialPort::CSerialPort(
	DWORD baudRate /* = 9600 */,
	BYTE byteSize /* = 8 */,
	BYTE parityBit /* = NOPARITY */,
	BYTE stopBit /* = ONESTOPBIT */
) : m_dwBaudRate(baudRate),
m_byteSize(byteSize),
m_parityBit(parityBit),
m_stopBit(stopBit),
m_bOpen(false)
{

}

CSerialPort::~CSerialPort()
{

}

// 打开串口成功,返回 true

bool CSerialPort::openComm()
{
	std::wstring realPort = _T("\\\\.\\") + m_portNum;
    m_hComm = CreateFile(realPort.c_str(),
                         GENERIC_READ | GENERIC_WRITE, //允许读和写
                         0,		//独占方式
                         NULL, 
						 OPEN_EXISTING,   //打开而不是创建
                         0,   //同步方式
                         NULL
                        );

    if(m_hComm == INVALID_HANDLE_VALUE)
    {
        int error = GetLastError();
		
        return false;

    }
    else
    {
		SetupComm(m_hComm, MAX_BUFFER_SIZE, MAX_BUFFER_SIZE);	// 设置读写缓冲区大小

		COMMTIMEOUTS TimeOuts; //设定读超时
		TimeOuts.ReadIntervalTimeout = MAXDWORD;
		TimeOuts.ReadTotalTimeoutMultiplier = 0;
		TimeOuts.ReadTotalTimeoutConstant = 0; //设定写超时
		TimeOuts.WriteTotalTimeoutMultiplier = 500;
		TimeOuts.WriteTotalTimeoutConstant = 2000;
		SetCommTimeouts(m_hComm, &TimeOuts); //设置超时

        DCB dcb;
        GetCommState(m_hComm, &dcb);
        dcb.BaudRate = m_dwBaudRate;
        dcb.ByteSize = m_byteSize;
        dcb.Parity = m_parityBit;
        dcb.StopBits = m_stopBit;

        if(!SetCommState(m_hComm, &dcb))
        {
            TCHAR szBuf[1024] = { 0 };
            wsprintf(szBuf, L"串口设置失败,错误代码: %d", GetLastError());
            //MessageBox(NULL, szBuf, TEXT("ERROR"), MB_OK);
            return false;
        }

    }

    //在读写串口前，用 PurgeComm 函数清空缓冲区
    BOOL ret = PurgeComm(m_hComm, PURGE_RXCLEAR | PURGE_TXCLEAR | PURGE_TXABORT | PURGE_TXABORT);
	if (!ret)
	{
		TCHAR szBuf[1024] = { 0 };
		wsprintf(szBuf, _T("清空缓冲区失败,错误代码: %d"), GetLastError());
		//MessageBox(NULL, szBuf, L"ERROR", MB_OK);
	}

    m_bOpen = true;

    return true;

}

// 关闭串口
void CSerialPort::closeComm()
{
	if (!m_bOpen)
	{
		return;
	}

    CloseHandle(m_hComm);
}


// 向串口发送数据
bool CSerialPort::writeToComm(BYTE data[], DWORD dwLength)
{
#ifdef _DEBUG
    assert(m_bOpen == true || dwLength > 0);
    //return false;
#endif // _DEBUG
    DWORD dwError = 0;

    if(ClearCommError(m_hComm, &dwError, NULL) && dwError > 0)
    {
        PurgeComm(m_hComm, PURGE_TXABORT | PURGE_TXCLEAR);
    }

    DWORD dwTx = 0;
    BOOL ret = FALSE;
    ret = WriteFile(m_hComm, data, dwLength, &dwTx, NULL);

    if(ret == FALSE)
    {
        TCHAR szBuf[1024] = { 0 };
        wsprintf(szBuf, _T("读取数据失败,错误代码: %d"), GetLastError());
        //MessageBox(NULL, szBuf, L"ERROR", MB_OK);

        return false;
    }

    return true;


}

// 从串口中读取数据
bool CSerialPort::readFromComm(char buffer[], DWORD dwLength, DWORD* nReaded)
{
#ifdef _DEBUG
    assert(m_bOpen == true || dwLength > 0);
    //return false;
#endif // _DEBUG

    COMSTAT comStat;
    DWORD dwError = 0;

    if(ClearCommError(m_hComm, &dwError, &comStat) && dwError > 0)
    {
        PurgeComm(m_hComm, PURGE_RXABORT | PURGE_RXCLEAR);
    }

    DWORD dwRx = 0;		// 读入的字节数
    BOOL ret = FALSE;
    ret = ReadFile(m_hComm, buffer, dwLength, &dwRx, NULL);	// 读入数据

    if(ret == TRUE)
    {
		*nReaded = dwRx;

        return true;
    }
    else
    {
		TCHAR szBuf[1024] = { 0 };
		wsprintf(szBuf, _T("读取数据失败,错误代码: %d"), GetLastError());
		//MessageBox(NULL, szBuf, L"ERROR", MB_OK);

        return false;
    }

    return true;
}