串行通讯口的实用编程 - 中国DOS联盟论坛

#include <Stdio.h>
#include <Stdlib.h>
#include <bios.h>
#include <dos.h>
#include <conio.h>
#include <string.h>

#include <symbol.h>
#include <DownComm.h>

int main()
{
BYTE byCh;
char buf[256];

CMotorNet mMotorNet; //使用通讯口COM1，波特率9600，8位数据位，1位起始位，1位停止位，无奇偶校验，查询方式
mMotorNet.Init(0x2F8, 9600, 8, 1, 1, NO_PARITY, FALSE); //如果中断方式, FALSE改为TRUE即可。
//发送一个字节
byData = 'W'
mMotorNet.SendData(byData);

//发送一个串
::_fstrcpy(buf, "This is WinSail V2.0!");
mMotorNet.SendBuffer(buf, _strlen(buf) + 1);

//接收一个数据
byCh = mMotorNet.ReceiveData();
if (byCh == 0 && GetLastCommError() == COMM_ERROR_CODE_TIME)
{
//这里没有读到数据
}
else
{
//这里读到了数据
}

//接收一个串，超时为165mS(=3 * 55mS)
int nCount = mMotorNet.ReceiveData(buf, 256, 3);
if (nCoun == 0)
{
//这里完全没有数据
}
else if (nCount != 256)
{
//这里不足256字节的数据
}
else
{
//这里读足了256字节数据
}

//接收8个字节的串，有超时处理
BOOL bSuccess = TRUE;
for (int i = 0; i < 8; i++)
{
if (!mMotorNet.WaitCommData(3)) //3 * 55mS超时
{
bSuccess = FALSE;
break;
}
buf[i] = mMotorNet.ReceiveData();
}
if (bSuccess)
{
//成功读到8个字节
}
else
{
//没有读到8个字节
}

//接收8个字节的串，无超时处理
for (int i = 0; i < 8; i++)
{
while (!mMotorNet.IsCommData())
{
}
buf[i] = mMotorNet.ReceiveData();
}

return(0);
}

//这里是DownComm.h文件

#ifndef _DOWN_COMMx_H_
#define _DOWN_COMMx_H_

#define COMM_ERROR_SUCCESS 0
#define COMM_ERROR_TIME -1
#define COMM_ERROR_USER -2
#define COMM_ERROR_CHECK -3
#define COMM_ERROR_BUSY -4
#define COMM_ERROR_DEFAULT -5
#define COMM_ERROR_OVER -6
#define COMM_ERROR_ADDRESS -7
#define COMM_ERROR_FORMAT -8
#define COMM_ERROR_ANSWER -9
#define COMM_ERROR_FILE -0xA
#define COMM_ERROR_READY -0xB
#define COMM_ERROR_CRAFT -0xC
#define COMM_ERROR_AGAIN -0xD
#define COMM_ERROR_BUFFER_FULL -0xE

#define CBR_50 50lu
#define CBR_110 110lu
#define CBR_300 300lu
#define CBR_600 600lu
#define CBR_1200 1200lu
#define CBR_2400 2400lu
#define CBR_4800 4800lu
#define CBR_9600 9600lu
#define CBR_14400 14400lu
#define CBR_19200 19200lu
#define CBR_38400 38400lu
#define CBR_56000 56000lu
#define CBR_57600 57600lu
#define CBR_115200 115200lu
#define CBR_128000 128000lu
#define CBR_256000 256000lu

#define NOPARITY 0
#define ODDPARITY 1
#define EVENPARITY 2
#define MARKPARITY 3
#define SPACEPARITY 4

#define ONESTOPBIT 0
#define ONE5STOPBITS 1
#define TWOSTOPBITS 2

#define DTR_CONTROL_DISABLE 0x00
#define DTR_CONTROL_ENABLE 0x01
#define DTR_CONTROL_HANDSHAKE 0x02

#define RTS_CONTROL_DISABLE 0x00
#define RTS_CONTROL_ENABLE 0x01
#define RTS_CONTROL_HANDSHAKE 0x02
#define RTS_CONTROL_TOGGLE 0x03

#define COMM_DB25_TXD 2 //数据发送端,输出
#define COMM_DB25_RXD 3 //数据接收端,输入
#define COMM_DB25_RTS 4 //请求发送(计算机要求发送数据),输出
#define COMM_DB25_CTS 5 //清除发送(MODEM准备接收数据),输入
#define COMM_DB25_DSR 6 //数据设备准备就绪,输入
#define COMM_DB25_SG 7 //信号地
#define COMM_DB25_DCD 8 //数据载波检测,输入
#define COMM_DB25_DTR 20 //数据终端准备就绪(计算机),输出
#define COMM_DB25_RI 22 //响铃指示,输入

#define COMM_DB9_TXD 3 //数据发送端,输出
#define COMM_DB9_RXD 2 //数据接收端,输入
#define COMM_DB9_RTS 7 //请求发送(计算机要求发送数据),输出
#define COMM_DB9_CTS 8 //清除发送(MODEM准备接收数据),输入
#define COMM_DB9_DSR 6 //数据设备准备就绪,输入
#define COMM_DB9_SG 5 //信号地
#define COMM_DB9_DCD 1 //数据载波检测,输入
#define COMM_DB9_DTR 4 //数据终端准备就绪(计算机),输出
#define COMM_DB9_RI 9 //响铃指示,输入

#define COMM_REGISTER_THR 0
#define COMM_REGISTER_RBR 0
#define COMM_REGISTER_BAUDL 0
#define COMM_REGISTER_BAUDH 1
#define COMM_REGISTER_IER 1
#define COMM_REGISTER_IIR 2
#define COMM_REGISTER_FCR 2
#define COMM_REGISTER_LCR 3
#define COMM_REGISTER_MCR 4
#define COMM_REGISTER_LSR 5
#define COMM_REGISTER_MSR 6
#define COMM_REGISTER_SR 7

typedef struct tagCOMMCONTROL
{
int nIRQ;
int nBase;
int nErrorCode;
void interrupt (*pOldFc) (...);

DWORD dwBaud;
WORD wDataBit;
WORD wStartBit;
WORD wStopBit;
WORD wParity;

BYTE* pBufferR; //输入缓冲区
int nSizeR; //输入缓冲区的尺寸
int nTailR; //输入缓冲区的尾指针
int nHeadR; //输入缓冲区的头指针
BOOL bFullR; //输入缓冲区的标志

BYTE* pBufferS; //输出缓冲区
int nSizeS; //输出缓冲区的尺寸
int nTailS; //输出缓冲区的尾指针
int nHeadS; //输出缓冲区的头指针
BOOL bFullS; //输出缓冲区的标志

}COMMCONTROL, *LPCOMMCONTROL;

class CMotorNet
{
private:
BOOL m_bInterrupt;
int m_nIRQ;

int m_nErrorCode;
private:
COMMCONTROL* GetCommControl();
void CloseInterrupt();
public:
void ChangeParity(WORD wParity);

void InitComm(int nBase, DWORD dwBaud, WORD wDataBit = 8, WORD wStartBit = 1,
WORD wStopBit = 1, WORD wParity = NOPARITY, BOOL bInterrupt = FALSE);
public:
BOOL IsCommData();
BOOL IsBusy();
BOOL WaitCommData(DWORD dwWait);

BYTE ReceiveData();
BOOL SendData(BYTE nCh);

int ReceiveBuffer(BYTE* pBuffer, int nCount, DWORD dwTimeOut = 0lu);
BOOL SendBuffer(BYTE* pBuffer, int nCount);

void ClearBufferR();
void ClearBufferS();
public:
int GetLastCommError(){return(m_nErrorCode);};
void SetLastCommError(int nErrorCode){m_nErrorCode=nErrorCode;}
void ClearLastCommError(){m_nErrorCode=COMM_ERROR_SUCCESS;}
public:
CMotorNet();
~CMotorNet();
};

#endif

[ Last edited by firstsail on 2008-9-25 at 05:55 PM ]


//这里是DownComm.Cpp文件

#include <string.h>
#include <dos.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys\\stat.h>
#include <io.h>
#include <conio.h>
#include <bios.h>

#include <symbol.h> //此文件可在“WinSail V2.0下载后获得”
#include <DownComm.h>


#define COMM_INTERRUPT_BUFFER_SIZE  1024
#define MEMORY_TIME_ADDRESS    0x46CL
#define COMM_TIME_DELAY       4L



COMMCONTROL Afx_CommControl3={3, 0x3F8, COMM_ERROR_SUCCESS, NULL};
COMMCONTROL Afx_CommControl4={4, 0x2F8, COMM_ERROR_SUCCESS, NULL};

//这是COMM口中断模式时的中断调用公共函数
void  COMM_PublicInterruptFc (COMMCONTROL* pCommControl)
{
    
    BYTE byData,byLin, byIIR;
    
    
    int nCommBase = pCommControl->nBase;;
    
    //Read and discard interrupt
    byData = inportb(nCommBase + COMM_REGISTER_LSR);
    
    //get interrupt status
    byIIR = inportb(nCommBase + COMM_REGISTER_IIR);
    
    
    //is interrupt?
    if (!!(byIIR & 0x1))
    {
        return;
    }
    
    byData = ((byIIR >> 1) & 0x3);
    
    if (byData == 0x2) //receive
    {
        if (!pCommControl->bFullR)
        {
            pCommControl->pBufferR =
            inportb(nCommBase + COMM_REGISTER_RBR);
            
            pCommControl->nTailR++;
            if (pCommControl->nTailR >= pCommControl->nSizeR)
            {
                pCommControl->nTailR = 0;
            }
            
            if (pCommControl->nTailR == pCommControl->nHeadR)
            {
                pCommControl->bFullR = TRUE;
            }
        }
    }
    else if (byData == 0x1) //send
    {
        if (pCommControl->nHeadS != pCommControl->nTailS ||
            pCommControl->bFullS)
        {
            outportb(nCommBase + COMM_REGISTER_RBR,
                pCommControl->pBufferS);
            
            pCommControl->nHeadS++;
            if (pCommControl->nHeadS >= pCommControl->nSizeS)
            {
                pCommControl->nHeadS = 0;
            }
            
            pCommControl->bFullS = FALSE;
        }
        
        //Is empty?
        if (pCommControl->nHeadS == pCommControl->nTailS)// && !pCommControl->bFullW)
        {
            byLin = inportb(nCommBase + COMM_REGISTER_LCR);
            byLin &= 0x7F;
            outportb(nCommBase + COMM_REGISTER_LCR, byLin);
            //force interrupt for send only
            outportb(nCommBase + COMM_REGISTER_IER, 0x1);
        }
        
        pCommControl->bFullS = FALSE;
    }
    else if (byData == 0x0) //Model status interrupt
    {
    }
    else if (byData == 0x3) //receive line status
    {
    }
    
    return;
}

//IRQ3中断函数
void interrupt CMotorNet_NewInterruptFc3 (...)
{
    asm mov ax, seg Afx_CommControl3
    asm mov ds, ax
    
    ::COMM_PublicInterruptFc (&Afx_CommControl3);
    
    outportb(0x20, 0x20);
    return;
}

//IRQ4中断函数
void interrupt CMotorNet_NewInterruptFc4 (...)
{
    asm mov ax, seg Afx_CommControl3
    asm mov ds, ax
    
    ::COMM_PublicInterruptFc (&Afx_CommControl4);
    
    outportb(0x20, 0x20);
    return;
}

//获得通讯控制包结构指针
COMMCONTROL* CMotorNet::GetCommControl()
{
    if (m_nIRQ == 3)
    {
        return (&Afx_CommControl3);
    }
    else
    {
        return (&Afx_CommControl4);
    }
}

//CMotorNet类的构造函数
CMotorNet::CMotorNet()
{
    m_bInterrupt         = FALSE;
    m_nIRQ               = 3;
    m_nErrorCode         = COMM_ERROR_SUCCESS;
}

//CMotorNet类的析构函数
CMotorNet::~CMotorNet()
{
    this->CloseInterrupt();
}

//在中断模式时，将中断模式转查询模式
void CMotorNet::CloseInterrupt()
{
    BYTE byData;
    
    COMMCONTROL* pCommControl = this->GetCommControl();
    
    asm pushf
    asm cli
    
    if (m_bInterrupt)
    {
        //mask irq
        byData = inportb(0x21);
        byData |= (1 << m_nIRQ);
        outportb(0x21, byData);
        
        //clear IER access bit,disable 8250 interrupt
        byData = inportb(pCommControl->nBase + COMM_REGISTER_LCR);
        byData &= 0x7F;
        outportb(pCommControl->nBase + COMM_REGISTER_LCR, byData);
        outportb(pCommControl->nBase + COMM_REGISTER_IER, 0x0);
        
        //other
        inportb(pCommControl->nBase +  COMM_REGISTER_RBR);
        inportb(pCommControl->nBase +  COMM_REGISTER_LSR);
        inportb(pCommControl->nBase +  COMM_REGISTER_IIR);
        inportb(pCommControl->nBase +  COMM_REGISTER_IER);
        inportb(pCommControl->nBase +  COMM_REGISTER_MSR);
        
        //disable 8250 RTS, DTR, ...
        outportb(pCommControl->nBase + COMM_REGISTER_MCR, 0);
        outportb(pCommControl->nBase + COMM_REGISTER_MCR, 0);
        
        
        if (pCommControl->pOldFc != NULL)
        {
            ::_dos_setvect(8 + m_nIRQ, pCommControl->pOldFc);
            pCommControl->pOldFc = NULL;
        }
        pCommControl->nHeadR = pCommControl->nHeadS = 0;
        pCommControl->nTailR = pCommControl->nTailS = 0;
        pCommControl->nSizeR = pCommControl->nSizeS = 0;
        pCommControl->bFullR = pCommControl->bFullS = FALSE;
        
        DELETE(pCommControl->pBufferR);
        DELETE(pCommControl->pBufferS);
        
        pCommControl->nErrorCode = COMM_ERROR_SUCCESS;
    }
    
    m_bInterrupt = FALSE;
    
    asm popf
    return;
}


//改变奇偶校验方式，特别适用于RS485传输时的“地址”和“数据”传输
void   CMotorNet::ChangeParity(WORD wParity)
{
    asm pushf
    asm cli
    
    COMMCONTROL* pCommControl = this->GetCommControl();
    
    BYTE byAttrib  = (BYTE)pCommControl->wAttrib;
    byAttrib  &= 0x7F;
    
    if (wParity == NOPARITY)   //B5,B4,B3 = xx0
    {
        byAttrib &= ~(1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5);
    }
    else if(wParity == ODDPARITY)  //B5,B4,B3 = 001
    {
        byAttrib |= (1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5);
    }
    else if (wParity == EVENPARITY)  //B5,B4,B3 = 011
    {
        byAttrib |= (1<<3); byAttrib |= (1<<4); byAttrib &= ~(1<<5);
    }
    else if (wParity == MARKPARITY)  //B5,B4,B3 = 101
    {
        byAttrib |= (1<<3); byAttrib &= ~(1<<4); byAttrib |= (1<<5);
    }
    else if (wParity == SPACEPARITY)  //B5,B4,B3 = 111
    {
        byAttrib |= (1<<3); byAttrib |= (1<<4); byAttrib |= (1<<5);
    }
    
    
    outportb(pCommControl->nBase + COMM_REGISTER_LCR, byAttrib);
    
    pCommControl->wParity = byAttrib;
    
    asm popf
    
    return;
}

//串行口初始化
void   CMotorNet::InitComm(int nBase,DWORD dwBaud,WORD wDataBit,
    WORD wStartBit,WORD wStopBit,WORD wParity, BOOL bInterrupt)
{
    BYTE byIRQMask;
    
    m_nErrorCode = COMM_ERROR_SUCCESS;
    
    
    if (m_bInterrupt)
    {
        this->CloseInterrupt();
    }
    
    
    //Modify IRQ
    if (nBase == 0x3F8 || nBase == 0x3E8) m_nIRQ = 4; //Com1
    if (nBase == 0x2F8 || nBase == 0x2E8) m_nIRQ = 3; //Com2
    
    COMMCONTROL* pCommControl = this->GetCommControl();
    
    //force interrupt
    outportb(nBase + COMM_REGISTER_IER, 0x00);
    
    //Set IRQ disable
    byIRQMask = inportb(0x21);
    outportb(0x21, byIRQMask |  (1 << m_nIRQ));
    
    
    //Modify Data Bit
    if(wDataBit < 5u || wDataBit > 8u)
    {
        wDataBit = 8;
    }
    
    //Modify StartBit
    wStartBit = 1;
    
    //Modify StopBit
    if (wStopBit != ONESTOPBIT &&
        wStopBit != ONE5STOPBITS &&
        wStopBit != TWOSTOPBITS)
    {
        wStopBit = ONESTOPBIT;
    }
    
    //Save Comm Attrib
    pCommControl->nBase         = nBase;
    pCommControl->dwBaud        = dwBaud;
    pCommControl->wDataBit      = wDataBit;
    pCommControl->wStartBit     = wStartBit;
    pCommControl->wStopBit      = wStopBit;
    pCommControl->wParity       = wParity;
    
    m_bInterrupt        = bInterrupt;
    
    
    //Write Baud
    outportb(nBase + COMM_REGISTER_LCR, 0x80); //baud-rate enable
    outportb(nBase + COMM_REGISTER_BAUDL, LOBYTE((115200L/ dwBaud)));
    outportb(nBase + COMM_REGISTER_BAUDH, HIBYTE((115200L/ dwBaud)));
    
    //Calc LCR Value
    BYTE byAttrib = 0u;
    if (wDataBit==5) {byAttrib &= ~(1<<1); byAttrib &= ~(1<<0);}//00
    if (wDataBit==6) {byAttrib &= ~(1<<1); byAttrib |=  (1<<0);}//01
    if (wDataBit==7) {byAttrib |=  (1<<1); byAttrib &= ~(1<<0);}//10
    if (wDataBit==8) {byAttrib |=  (1<<1); byAttrib |=  (1<<0);}//11
    
    if (wStopBit == ONESTOPBIT)   byAttrib &= ~(1<<2);
    if (wStopBit == ONE5STOPBITS) byAttrib |=  (1<<2);
    if (wStopBit == TWOSTOPBITS)  byAttrib |=  (1<<2);
    
    if (wParity == NOPARITY)
    {
        byAttrib &= ~(1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5);
    }
    else if(wParity == ODDPARITY)
    {
        byAttrib |= (1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5);
    }
    else if (wParity == EVENPARITY)
    {
        byAttrib |= (1<<3); byAttrib |= (1<<4); byAttrib &= ~(1<<5);
    }
    else if (wParity == MARKPARITY)
    {
        byAttrib |= (1<<3); byAttrib &= ~(1<<4); byAttrib |= (1<<5);
    }
    else if (wParity == SPACEPARITY)
    {
        byAttrib |= (1<<3); byAttrib |= (1<<4); byAttrib |= (1<<5);
    }
    
    //write start bit, stop bit, parity
    outportb(nBase + COMM_REGISTER_LCR, byAttrib);
    
    //Moden control 00000110B
    outportb(nBase + COMM_REGISTER_MCR, 0x03);
    
    if (bInterrupt)
    {
        COMMCONTROL* pCommControl = this->GetCommControl();
        
        this->CloseInterrupt();
        m_bInterrupt = TRUE;
        
        
        asm  pushf
        asm  cli
        
        
        //Malloc buffer for read and write
        pCommControl->nIRQ = m_nIRQ;
        pCommControl->nBase = nBase;
        pCommControl->nErrorCode = COMM_ERROR_SUCCESS;
        pCommControl->pBufferR = new BYTE;
        pCommControl->pBufferS = new BYTE;
        pCommControl->nHeadR = pCommControl->nHeadS = 0;
        pCommControl->nTailR = pCommControl->nTailS = 0;
        pCommControl->nSizeR = pCommControl->nSizeS = COMM_INTERRUPT_BUFFER_SIZE;
        pCommControl->bFullR = pCommControl->bFullS = FALSE;
        
        asm cli
        
        
        //get old vect
        pCommControl->pOldFc = ::_dos_getvect(m_nIRQ + 8);
        
        //Set Interrupt Fc
        if (m_nIRQ == 3)
        {
            ::_dos_setvect(m_nIRQ + 8, CMotorNet_NewInterruptFc3);
        }
        else
        {
            ::_dos_setvect(m_nIRQ + 8, CMotorNet_NewInterruptFc4);
        }
        
        
        asm cli
        
        //Set IRQ Enable
        byIRQMask = inportb(0x21);
        outportb(0x21, byIRQMask & (~(1 << m_nIRQ)));
        
        //discard LSR
        inportb(nBase + COMM_REGISTER_LSR);
        
        //discard MSR
        inportb(nBase + COMM_REGISTER_MSR);
        
        //discard RBR
        inportb(nBase + COMM_REGISTER_RBR);
        
        //LCR Bit7->0
        byAttrib = inportb(nBase + COMM_REGISTER_LCR);
        byAttrib &= 0x7F;
        outportb(nBase + COMM_REGISTER_LCR, byAttrib);
        
        //permit interrupt  for receive data ,00000001B
        outportb(nBase + COMM_REGISTER_IER, 0x1);
        
        //Model control,00001100B
        outportb(nBase + COMM_REGISTER_MCR, 0xB);
        
        //FIFO control,00000000B
        outportb(nBase + COMM_REGISTER_FCR, 0x0);
        
        asm popf
    }
}

//中断模式时，用于清空输入缓冲区
void    CMotorNet::ClearBufferR()
{
    asm pushf
    asm cli
    
    COMMCONTROL* pCommControl = this->GetCommControl();
    pCommControl->nHeadR = pCommControl->nTailR = 0;
    pCommControl->bFullR = FALSE;
    
    
    asm popf
}

//中断模式时，用于清空输出缓冲区
void    CMotorNet::ClearBufferS()
{
    asm pushf
    asm cli
    
    COMMCONTROL* pCommControl = this->GetCommControl();
    pCommControl->nHeadS = pCommControl->nTailS = 0;
    pCommControl->bFullS = FALSE;
    
    
    asm popf
    
}

//判断是否有数据可读
BOOL CMotorNet::IsCommData()
{
    COMMCONTROL* pCommControl = this->GetCommControl();
    
    if (!m_bInterrupt)
    {
        return((inportb(pCommControl->nBase + COMM_REGISTER_LSR)&0x01));
    }
    else
    {
        if (pCommControl->nHeadR != pCommControl->nTailR ||
            pCommControl->bFullR)
        {
            return (TRUE);
        }
        
    }
    
    return(FALSE);
}

//在规定的时间内等待数据的到来，
BOOL CMotorNet::WaitCommData(DWORD dwWait)
{
    DWORD  far *pdwMemoryTime = (DWORD far *)MEMORY_TIME_ADDRESS;
    DWORD  dwTime = *pdwMemoryTime;
    
    //This maybe dead lock, you need modify code!!!
    while (!this->IsCommData())//(inportb(m_nCommBase+5) & 0x01))
    {
        if (*pdwMemoryTime - dwTime >= dwWait)
        {
            return(FALSE);
        }
    }
    return(TRUE);
}

//接收一个字节
BYTE CMotorNet::ReceiveData()
{
    m_nErrorCode = COMM_ERROR_SUCCESS;
    
    if (!this->WaitCommData(COMM_TIME_DELAY))
    {
        m_nErrorCode = COMM_ERROR_TIME;
        return(0);
    }
    
    COMMCONTROL* pCommControl = this->GetCommControl();
    
    if (m_bInterrupt)
    {
        
        asm pushf
        asm cli
        
        BYTE byData = pCommControl->pBufferR;
        pCommControl->nHeadR = pCommControl->nHeadR + 1;
        if (pCommControl->nHeadR >= pCommControl->nSizeR)
        {
            pCommControl->nHeadR = 0;
        }
        pCommControl->bFullR = FALSE;
        
        asm popf
        return(byData);
    }
    else
    {
        return(inportb(pCommControl->nBase));
    }
}

//发送一个字节
BOOL CMotorNet::SendData(BYTE nCh)
{
    COMMCONTROL* pCommControl = this->GetCommControl();
    
    
    if (!m_bInterrupt)
    {
        while (this->IsCommData())
        {
            this->ReceiveData();
        }
        
        DWORD  far *pdwMemoryTime=(DWORD far *)MEMORY_TIME_ADDRESS;
        DWORD  dwTime = *pdwMemoryTime;
        
        //DWORD dwCount=0;
        while (!(inportb(pCommControl->nBase + COMM_REGISTER_LSR) & 0x20))
        {
            if (*pdwMemoryTime - dwTime > COMM_TIME_DELAY) //100
            {
                m_nErrorCode = COMM_ERROR_TIME;
                return(FALSE);
            }
        }
        
        outportb(pCommControl->nBase,nCh);
    }
    else
    {
        if (pCommControl->bFullS)
        {
            return (FALSE);
        }
        
        asm pushf
        asm cli
        
        pCommControl->pBufferS = nCh;
        pCommControl->nTailS = pCommControl->nTailS + 1;
        if (pCommControl->nTailS >= pCommControl->nSizeS)
        {
            pCommControl->nTailS = 0;
        }
        
        if (pCommControl->nTailS == pCommControl->nHeadS)
        {
            pCommControl->bFullS = TRUE;
        }
        
        //permit interrupt  for receive and send data ,00000011B
        outportb(pCommControl->nBase + COMM_REGISTER_IER, 0x3);
        
        asm popf
    }
    return(TRUE);
}

//接收多个字节
int	CMotorNet::ReceiveBuffer(BYTE* pBuffer, int nCount, DWORD dwTimeOut)
{
    for (int i = 0; i < nCount; i++)
    {
        if (!this->WaitCommData(dwTimeOut))
        {
            return (i);
        }
        pBuffer = this->ReceiveData();
    }
    
    return (nCount);
}

//发送多个字节
BOOL	CMotorNet::SendBuffer(BYTE* pBuffer, int nCount)
{
    for (int i = 0; i < nCount; i++)
    {
        if (!this->SendData(pBuffer))
        {
            //在中断模式时，一直等到缓冲区不为空
            if (m_bInterrupt && this->GetCommControl()->bFullS)
            {
                i--;
                continue;
            }
            return (FALSE);
        }
    }
    
    return (TRUE);
    
}

//判断总线是否忙
//常用于RS485发送端，一般情况下如果忙，须清空输入缓冲区
BOOL CMotorNet::IsBusy()
{
    this->ClearLastCommError();
    return (this->IsCommData());
}

//此文件为WinSail V2.0下载后的“功能类_CMotorNet类串行通讯详细设计.DOC”文件

2 类简介
类名为CMotorNet，头文件是“DownComm.h”。

3 类成员函数
3.1 IsCommData()
原型：BOOL IsCommData();
作用：判断是否有数据可读
入口参数：无
出口参数：无
返回值：有数据可读返回TRUE，否则返回FALSE。

3.2 IsBusy()
原型：BOOL IsBusy();
作用：判断是否有数据可读,与IsCommData()函数作为相同
入口参数：无
出口参数：无
返回值：有数据可读返回TRUE，否则返回FALSE。

3.3 WaitCommData()
原型：BOOL WaitCommData(DWORD dwWait);
作用：在指定的时间内等待有数据可读
入口参数：DWORD dwWait ---- 时间计数值，以55mS为单位
出口参数：无
返回值：成功返回TRUE，否则返回FALSE

3.4 SendData()
原型：BOOL SendData(BYTE byCh);
作用：发送一个字节
入口参数：BYTE byCh ---- 需发送的字节
出口参数：无
返回值：成功发送返回TRUE，否则返回FALSE

3.5 ReceiveData()
原型：BYTE ReceiveData();
作用：接收一个字节
入口参数：无
出口参数：无
返回值：成功返回数据值；否则返回0，并置通讯错误代码为COMM_ERROR_TIME

3.6 ReceiveBuffer()
原型：int ReceiveBuffer(BYTE* pBuffer, int nCount ,DWORD dwTimeOut = 0lu);
作用：接收多个字节
入口参数： int nCount----------需读取的字节数
DWORD dwTimeOut-----超时时间，以55mS为单位
出口参数：BYTE* pBuffer-------缓冲区首地址
返回值：返回接收的字节数

3.7 Void SendBuffer()
原型：void Re();
作用：发送多个字节
入口参数：无
出口参数：无
返回值：无

3.8 Void ClearBufferR()
原型：void ClearBufferR();
作用：在中断模式下，清除接收缓冲区
入口参数：无
出口参数：无
返回值：无

3.9 Void ClearBufferS()
原型：void ClearBufferS();
作用：在中断模式下，清除发送缓冲区
入口参数：无
出口参数：无
返回值：无

3.10 ChangeParity()
原型：void ChangeParity(WORD wParity);
作用：修改奇偶校验属性
入口参数：WORD wParity --- 奇偶校验属性，见InitComm()函数
出口参数：无
返回值：无

3.11 Void InitComm()
原型：void InitComm(int nBase, DWORD dwBaud, WORD wDataBit = 8, WORD wStartBit = 1,
WORD wStopBit = 1, WORD wParityStyle = NOPARITY, BOOL bInterrupt = FALSE);
作用：初始化通迅口
入口参数：int nBase --- 通讯口在基地址
COM1 = 0x3F8 COM2 = 0x2F8
COM3 = 0x3E8 COM4 = 0x2E8
DWORD dwBaud-----波特率，其值如下
CBR_50 50波特率
CBR_110 110波特率
CBR_300 300波特率
CBR_600 600波特率
CBR_1200 1200波特率
CBR_2400 2400波特率
CBR_4800 4800波特率
CBR_9600 9600波特率
CBR_14400 14400波特率
CBR_19200 19200波特率
CBR_38400 38400波特率
CBR_56000 56000波特率
CBR_57600 57600波特率
CBR_115200 115200波特率
CBR_128000 128000波特率
CBR_256000 256000波特率
WORD wDataBit---------数据位，值为5，6，7，8
WORD wStartBit--------起始位，值固定为“1”
WORD wStopBit---------停止位，取值如下
ONESTOPBIT 1位停止位
ONE5STOPBITS 1.5位停止位
TWOSTOPBITS 2位停止位
WORD wParityStyle-----奇偶校验
NOPARITY 无校验
ODDPARITY 奇校验
EVENPARITY 偶校验
MARKPARITY 校验位永为“1”
SPACEPARITY 校验位永为“0”
BOOL bInterrupt-------中断模式，TRUE为中断模式，FALSE为查询模式
出口参数：无
返回值：无

3.12 int GetLastCommError()
原型：int GetLastCommError();
作用：获得通讯错误代码
入口参数：无
出口参数：无
返回值：通讯错误代码。如果没有通讯错误，返回COMM_ERROR_SUCCESS

3.13 void SetLastCommError ()
原型：void SetLastCommError (int nErrorCode);
作用：设置通讯错误代码
入口参数：int nErrorCode--------错误代码
出口参数：无
返回值：无

3.14 Void ClearLastCommError ()
原型：int GetLastCommError();
作用：清除通讯错误代码
入口参数：无
出口参数：无
返回值：无

[ Last edited by firstsail on 2008-9-25 at 06:20 PM ]

1.2 RS232的寄存器
RS232共有12个寄存器

序号地址名称信号方向
1 Base + 0 发送保持寄存器只写
2 Base + 0 接收数据寄存器只读
3 Base + 0 除数锁存寄存器（LSB），波特率低八位可读写
4 Base + 1 除数锁存寄存器（MSB），波特率高八位可读写
5 Base + 1 IER----中断启用寄存器只读
6 Base + 2 IIR----中断标识寄存器只读
7 Base + 2 FCR----FIFO寄存器只写
8 Base + 3 LCR----线路控制寄存器可读写
9 Base + 4 MCR----MODEM控制寄存器可读写
10 Base + 5 LSR----线路状态寄存器只读
11 Base + 6 MSR----MODEM状态寄存器只读
12 Base + 7 暂时存储寄存器可读写

IER = base + 1, 中断启用寄存器
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |_____允许接收数据就绪中断,置1时允许接收到数据时产生中断
| | | | | | |_________允许发送保持器空中断,置1时允许发送保持寄存器空时产生中断
| | | | | |_____________允许接收线路状态中断，即置1时将在LSR变化时产生中断
| | | | |_________________允许MODEM状态中断，即置1时将在MSR变化时产生中断
| | | |_____________________进入睡眠模式（16750）
| | |_________________________进入低功耗模式（16750）
| |_____________________________未使用
|_________________________________未使用

IIR = base + 2, 中断识别寄存器，只读属性
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |_____指示是否有中断发生
| | | | | | | 0:有中断发生
| | | | | | | 1:无中断发生
| | | | | | |
| | | | | |___\_________标识具体的中断类型,中断具有优先级,LSR最高,MSR最低
| | | | | 00:MODEL状态中断(CTS/RI/DTR/DCD)
| | | | | 01:发送保持寄存器空中断
| | | | | 10:接收数据就绪中断
| | | | | 11:接收线路状态中断
| | | | |_________________超时中断(16550/16750)
| | | |_____________________未使用
| | |_________________________允许64字节FIFO(16550/16750)
| |
|___\_____________________________00:无FIFO(此时是8250/16450芯片)
01:允许FIFO,但不可用
11:允许FIFO

FCR = base + 2, FIFO控制寄存器，只写属性
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |_____允许FIFO
| | | | | | |_________清除接收FIFO
| | | | | |_____________清除发送FIFO
| | | | |_________________DMA模式选择
| | | |_____________________未使用
| | |_________________________允许64字节FIFO
| |
|___\_____________________________00:1Byte产生中断
01:4Byte产生中断
11:8Byte产生中断
11:14Byte产生中断

LCR = base + 3, 线路控制寄存器,可读/写
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |
| | | | | | |___\_____00:5位数据位
| | | | | | 01:6位数据位
| | | | | | 10:7位数据位
| | | | | | 11:8位数据位
| | | | | |_____________0->1位停止位;1->2位停止位(6,7,8);1->1.5位停止位(5)
| | | | |
| | | | |
| | |___\___\_________________XX0:无校验
| | 001:奇校验
| | 011:偶校验
| | 101:奇偶保持为1
| | 111:奇偶保持为0
| |_____________________________设置间断，0-禁止，1-设置
|_________________________________0:允许访问接收/发送及中断允许寄存器
1:允许访问波特率因子寄存器

MCR = base + 4, MODEM控制寄存器,可读/写
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |_____设置DSR
| | | | | | |_________设置RTS
| | | | | |_____________辅助输出1
| | | | |_________________辅助输出2
| | | |_____________________环路测试
| | |_________________________自动流量控制（仅16750）
| |_____________________________未使用
|_________________________________未使用

LSR = base + 5, 线路状态寄存器,只读
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |_____接收数据就绪
| | | | | | |_________超越错
| | | | | |_____________奇偶错
| | | | |_________________帧格式错
| | | |_____________________间断
| | |_________________________发送保持寄存器空
| |_____________________________发送移位寄存器空
|_________________________________FIFO中接收数据错误

MSR = base + 6, MODEM状态寄存器,只读
B7, B6, B5, B4, B3, B2, B1, B0
| | | | | | | |_____CTS已改变
| | | | | | |_________DSR已改变
| | | | | |_____________RI已改变
| | | | |_________________DCD已改变
| | | |_____________________CTS有效
| | |_________________________DSR准备就绪
| |_____________________________响铃指示
|_________________________________载波检测

1.3 波特率的计算
是用1.8432MHz时钟经过16分频的时钟（115200Hz）作为被除数，波特率作为除数，余数写入除数锁存寄存器中。
BYTE wDivL = LOBYTE(115200L/(DWORD)wBaud);
BYTE wDivH = HIBYTE(115200L/ (DWORD)wBaud);

DOS系统最多支持4个通讯口，分别为COM1、COM2、COM3、COM4。基地址分别对应于0x3F8、0x2F8、0x3E8、0x2E8。

RS232电缆一般是DB25或DB9物理接口，其意义如下：
DB25 DB9 信号名称方向含义
2 3 TXD 输出数据发送端
3 2 RXD 输入数据接收端
4 7 RTS 输出请求发送（计算机要求发送数据）,低电平有效
5 8 CTS 输入清除发送（MODEM准备接收数据）,低电平有效
6 6 DSR 输入数据设备准备就绪,低电平有效
7 5 GND 信号地
8 1 DCD 输入数据载波检测,低电平有效
20 4 DTR 输出数据终端准备就绪（计算机）,低电平有效
22 9 RI 输入响铃指示

在RS323电缆中，随着电缆长度的增加，信号遇到的电容就越多，从而使得数据的高速传输变得不可靠。并不是说在通讯时所有的管脚都被用上，这依赖于软件设计，但最简单的采用三线互联，RXD<—>TXD、TXD<—>RXD，GND<-->GND。

第1楼　firstsail	发表于 2008-09-25 17:49
高级用户　发帖 295　积分 668　来自广东深圳
串行通讯口的实用编程[1] #include <Stdio.h> #include <Stdlib.h> #include <bios.h> #include <dos.h> #include <conio.h> #include <string.h> #include <symbol.h> #include <DownComm.h> int main() { BYTE byCh; char buf[256]; CMotorNet mMotorNet; //使用通讯口COM1，波特率9600，8位数据位，1位起始位，1位停止位，无奇偶校验，查询方式 mMotorNet.Init(0x2F8, 9600, 8, 1, 1, NO_PARITY, FALSE); //如果中断方式, FALSE改为TRUE即可。 //发送一个字节 byData = 'W' mMotorNet.SendData(byData); //发送一个串 ::_fstrcpy(buf, "This is WinSail V2.0!"); mMotorNet.SendBuffer(buf, _strlen(buf) + 1); //接收一个数据 byCh = mMotorNet.ReceiveData(); if (byCh == 0 && GetLastCommError() == COMM_ERROR_CODE_TIME) { //这里没有读到数据 } else { //这里读到了数据 } //接收一个串，超时为165mS(=3 * 55mS) int nCount = mMotorNet.ReceiveData(buf, 256, 3); if (nCoun == 0) { //这里完全没有数据 } else if (nCount != 256) { //这里不足256字节的数据 } else { //这里读足了256字节数据 } //接收8个字节的串，有超时处理 BOOL bSuccess = TRUE; for (int i = 0; i < 8; i++) { if (!mMotorNet.WaitCommData(3)) //3 * 55mS超时 { bSuccess = FALSE; break; } buf[i] = mMotorNet.ReceiveData(); } if (bSuccess) { //成功读到8个字节 } else { //没有读到8个字节 } //接收8个字节的串，无超时处理 for (int i = 0; i < 8; i++) { while (!mMotorNet.IsCommData()) { } buf[i] = mMotorNet.ReceiveData(); } return(0); }

第2楼　firstsail	发表于 2008-09-25 17:51
高级用户　发帖 295　积分 668　来自广东深圳
串行通讯口的实用编程[2] //这里是DownComm.h文件 #ifndef _DOWN_COMMx_H_ #define _DOWN_COMMx_H_ #define COMM_ERROR_SUCCESS 0 #define COMM_ERROR_TIME -1 #define COMM_ERROR_USER -2 #define COMM_ERROR_CHECK -3 #define COMM_ERROR_BUSY -4 #define COMM_ERROR_DEFAULT -5 #define COMM_ERROR_OVER -6 #define COMM_ERROR_ADDRESS -7 #define COMM_ERROR_FORMAT -8 #define COMM_ERROR_ANSWER -9 #define COMM_ERROR_FILE -0xA #define COMM_ERROR_READY -0xB #define COMM_ERROR_CRAFT -0xC #define COMM_ERROR_AGAIN -0xD #define COMM_ERROR_BUFFER_FULL -0xE #define CBR_50 50lu #define CBR_110 110lu #define CBR_300 300lu #define CBR_600 600lu #define CBR_1200 1200lu #define CBR_2400 2400lu #define CBR_4800 4800lu #define CBR_9600 9600lu #define CBR_14400 14400lu #define CBR_19200 19200lu #define CBR_38400 38400lu #define CBR_56000 56000lu #define CBR_57600 57600lu #define CBR_115200 115200lu #define CBR_128000 128000lu #define CBR_256000 256000lu #define NOPARITY 0 #define ODDPARITY 1 #define EVENPARITY 2 #define MARKPARITY 3 #define SPACEPARITY 4 #define ONESTOPBIT 0 #define ONE5STOPBITS 1 #define TWOSTOPBITS 2 #define DTR_CONTROL_DISABLE 0x00 #define DTR_CONTROL_ENABLE 0x01 #define DTR_CONTROL_HANDSHAKE 0x02 #define RTS_CONTROL_DISABLE 0x00 #define RTS_CONTROL_ENABLE 0x01 #define RTS_CONTROL_HANDSHAKE 0x02 #define RTS_CONTROL_TOGGLE 0x03 #define COMM_DB25_TXD 2 //数据发送端,输出 #define COMM_DB25_RXD 3 //数据接收端,输入 #define COMM_DB25_RTS 4 //请求发送(计算机要求发送数据),输出 #define COMM_DB25_CTS 5 //清除发送(MODEM准备接收数据),输入 #define COMM_DB25_DSR 6 //数据设备准备就绪,输入 #define COMM_DB25_SG 7 //信号地 #define COMM_DB25_DCD 8 //数据载波检测,输入 #define COMM_DB25_DTR 20 //数据终端准备就绪(计算机),输出 #define COMM_DB25_RI 22 //响铃指示,输入 #define COMM_DB9_TXD 3 //数据发送端,输出 #define COMM_DB9_RXD 2 //数据接收端,输入 #define COMM_DB9_RTS 7 //请求发送(计算机要求发送数据),输出 #define COMM_DB9_CTS 8 //清除发送(MODEM准备接收数据),输入 #define COMM_DB9_DSR 6 //数据设备准备就绪,输入 #define COMM_DB9_SG 5 //信号地 #define COMM_DB9_DCD 1 //数据载波检测,输入 #define COMM_DB9_DTR 4 //数据终端准备就绪(计算机),输出 #define COMM_DB9_RI 9 //响铃指示,输入 #define COMM_REGISTER_THR 0 #define COMM_REGISTER_RBR 0 #define COMM_REGISTER_BAUDL 0 #define COMM_REGISTER_BAUDH 1 #define COMM_REGISTER_IER 1 #define COMM_REGISTER_IIR 2 #define COMM_REGISTER_FCR 2 #define COMM_REGISTER_LCR 3 #define COMM_REGISTER_MCR 4 #define COMM_REGISTER_LSR 5 #define COMM_REGISTER_MSR 6 #define COMM_REGISTER_SR 7 typedef struct tagCOMMCONTROL { int nIRQ; int nBase; int nErrorCode; void interrupt (pOldFc) (...); DWORD dwBaud; WORD wDataBit; WORD wStartBit; WORD wStopBit; WORD wParity; BYTE pBufferR; //输入缓冲区 int nSizeR; //输入缓冲区的尺寸 int nTailR; //输入缓冲区的尾指针 int nHeadR; //输入缓冲区的头指针 BOOL bFullR; //输入缓冲区的标志 BYTE* pBufferS; //输出缓冲区 int nSizeS; //输出缓冲区的尺寸 int nTailS; //输出缓冲区的尾指针 int nHeadS; //输出缓冲区的头指针 BOOL bFullS; //输出缓冲区的标志 }COMMCONTROL, LPCOMMCONTROL; class CMotorNet { private: BOOL m_bInterrupt; int m_nIRQ; int m_nErrorCode; private: COMMCONTROL GetCommControl(); void CloseInterrupt(); public: void ChangeParity(WORD wParity); void InitComm(int nBase, DWORD dwBaud, WORD wDataBit = 8, WORD wStartBit = 1, WORD wStopBit = 1, WORD wParity = NOPARITY, BOOL bInterrupt = FALSE); public: BOOL IsCommData(); BOOL IsBusy(); BOOL WaitCommData(DWORD dwWait); BYTE ReceiveData(); BOOL SendData(BYTE nCh); int ReceiveBuffer(BYTE* pBuffer, int nCount, DWORD dwTimeOut = 0lu); BOOL SendBuffer(BYTE* pBuffer, int nCount); void ClearBufferR(); void ClearBufferS(); public: int GetLastCommError(){return(m_nErrorCode);}; void SetLastCommError(int nErrorCode){m_nErrorCode=nErrorCode;} void ClearLastCommError(){m_nErrorCode=COMM_ERROR_SUCCESS;} public: CMotorNet(); ~CMotorNet(); }; #endif [ Last edited by firstsail on 2008-9-25 at 05:55 PM ]

第3楼　firstsail	发表于 2008-09-25 17:52
高级用户　发帖 295　积分 668　来自广东深圳
串行通讯口的实用编程[3] //这里是DownComm.Cpp文件 #include <string.h> #include <dos.h> #include <math.h> #include <stdio.h> #include <stdlib.h> #include <sys\\stat.h> #include <io.h> #include <conio.h> #include <bios.h> #include <symbol.h> //此文件可在“WinSail V2.0下载后获得” #include <DownComm.h> #define COMM_INTERRUPT_BUFFER_SIZE 1024 #define MEMORY_TIME_ADDRESS 0x46CL #define COMM_TIME_DELAY 4L COMMCONTROL Afx_CommControl3={3, 0x3F8, COMM_ERROR_SUCCESS, NULL}; COMMCONTROL Afx_CommControl4={4, 0x2F8, COMM_ERROR_SUCCESS, NULL}; //这是COMM口中断模式时的中断调用公共函数 void COMM_PublicInterruptFc (COMMCONTROL* pCommControl) { BYTE byData,byLin, byIIR; int nCommBase = pCommControl->nBase;; //Read and discard interrupt byData = inportb(nCommBase + COMM_REGISTER_LSR); //get interrupt status byIIR = inportb(nCommBase + COMM_REGISTER_IIR); //is interrupt? if (!!(byIIR & 0x1)) { return; } byData = ((byIIR >> 1) & 0x3); if (byData == 0x2) //receive { if (!pCommControl->bFullR) { pCommControl->pBufferR = inportb(nCommBase + COMM_REGISTER_RBR); pCommControl->nTailR++; if (pCommControl->nTailR >= pCommControl->nSizeR) { pCommControl->nTailR = 0; } if (pCommControl->nTailR == pCommControl->nHeadR) { pCommControl->bFullR = TRUE; } } } else if (byData == 0x1) //send { if (pCommControl->nHeadS != pCommControl->nTailS \|\| pCommControl->bFullS) { outportb(nCommBase + COMM_REGISTER_RBR, pCommControl->pBufferS); pCommControl->nHeadS++; if (pCommControl->nHeadS >= pCommControl->nSizeS) { pCommControl->nHeadS = 0; } pCommControl->bFullS = FALSE; } //Is empty? if (pCommControl->nHeadS == pCommControl->nTailS)// && !pCommControl->bFullW) { byLin = inportb(nCommBase + COMM_REGISTER_LCR); byLin &= 0x7F; outportb(nCommBase + COMM_REGISTER_LCR, byLin); //force interrupt for send only outportb(nCommBase + COMM_REGISTER_IER, 0x1); } pCommControl->bFullS = FALSE; } else if (byData == 0x0) //Model status interrupt { } else if (byData == 0x3) //receive line status { } return; } //IRQ3中断函数 void interrupt CMotorNet_NewInterruptFc3 (...) { asm mov ax, seg Afx_CommControl3 asm mov ds, ax ::COMM_PublicInterruptFc (&Afx_CommControl3); outportb(0x20, 0x20); return; } //IRQ4中断函数 void interrupt CMotorNet_NewInterruptFc4 (...) { asm mov ax, seg Afx_CommControl3 asm mov ds, ax ::COMM_PublicInterruptFc (&Afx_CommControl4); outportb(0x20, 0x20); return; } //获得通讯控制包结构指针 COMMCONTROL* CMotorNet::GetCommControl() { if (m_nIRQ == 3) { return (&Afx_CommControl3); } else { return (&Afx_CommControl4); } } //CMotorNet类的构造函数 CMotorNet::CMotorNet() { m_bInterrupt = FALSE; m_nIRQ = 3; m_nErrorCode = COMM_ERROR_SUCCESS; } //CMotorNet类的析构函数 CMotorNet::~CMotorNet() { this->CloseInterrupt(); } //在中断模式时，将中断模式转查询模式 void CMotorNet::CloseInterrupt() { BYTE byData; COMMCONTROL* pCommControl = this->GetCommControl(); asm pushf asm cli if (m_bInterrupt) { //mask irq byData = inportb(0x21); byData \|= (1 << m_nIRQ); outportb(0x21, byData); //clear IER access bit,disable 8250 interrupt byData = inportb(pCommControl->nBase + COMM_REGISTER_LCR); byData &= 0x7F; outportb(pCommControl->nBase + COMM_REGISTER_LCR, byData); outportb(pCommControl->nBase + COMM_REGISTER_IER, 0x0); //other inportb(pCommControl->nBase + COMM_REGISTER_RBR); inportb(pCommControl->nBase + COMM_REGISTER_LSR); inportb(pCommControl->nBase + COMM_REGISTER_IIR); inportb(pCommControl->nBase + COMM_REGISTER_IER); inportb(pCommControl->nBase + COMM_REGISTER_MSR); //disable 8250 RTS, DTR, ... outportb(pCommControl->nBase + COMM_REGISTER_MCR, 0); outportb(pCommControl->nBase + COMM_REGISTER_MCR, 0); if (pCommControl->pOldFc != NULL) { ::_dos_setvect(8 + m_nIRQ, pCommControl->pOldFc); pCommControl->pOldFc = NULL; } pCommControl->nHeadR = pCommControl->nHeadS = 0; pCommControl->nTailR = pCommControl->nTailS = 0; pCommControl->nSizeR = pCommControl->nSizeS = 0; pCommControl->bFullR = pCommControl->bFullS = FALSE; DELETE(pCommControl->pBufferR); DELETE(pCommControl->pBufferS); pCommControl->nErrorCode = COMM_ERROR_SUCCESS; } m_bInterrupt = FALSE; asm popf return; } //改变奇偶校验方式，特别适用于RS485传输时的“地址”和“数据”传输 void CMotorNet::ChangeParity(WORD wParity) { asm pushf asm cli COMMCONTROL* pCommControl = this->GetCommControl(); BYTE byAttrib = (BYTE)pCommControl->wAttrib; byAttrib &= 0x7F; if (wParity == NOPARITY) //B5,B4,B3 = xx0 { byAttrib &= ~(1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5); } else if(wParity == ODDPARITY) //B5,B4,B3 = 001 { byAttrib \|= (1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5); } else if (wParity == EVENPARITY) //B5,B4,B3 = 011 { byAttrib \|= (1<<3); byAttrib \|= (1<<4); byAttrib &= ~(1<<5); } else if (wParity == MARKPARITY) //B5,B4,B3 = 101 { byAttrib \|= (1<<3); byAttrib &= ~(1<<4); byAttrib \|= (1<<5); } else if (wParity == SPACEPARITY) //B5,B4,B3 = 111 { byAttrib \|= (1<<3); byAttrib \|= (1<<4); byAttrib \|= (1<<5); } outportb(pCommControl->nBase + COMM_REGISTER_LCR, byAttrib); pCommControl->wParity = byAttrib; asm popf return; } //串行口初始化 void CMotorNet::InitComm(int nBase,DWORD dwBaud,WORD wDataBit, WORD wStartBit,WORD wStopBit,WORD wParity, BOOL bInterrupt) { BYTE byIRQMask; m_nErrorCode = COMM_ERROR_SUCCESS; if (m_bInterrupt) { this->CloseInterrupt(); } //Modify IRQ if (nBase == 0x3F8 \|\| nBase == 0x3E8) m_nIRQ = 4; //Com1 if (nBase == 0x2F8 \|\| nBase == 0x2E8) m_nIRQ = 3; //Com2 COMMCONTROL* pCommControl = this->GetCommControl(); //force interrupt outportb(nBase + COMM_REGISTER_IER, 0x00); //Set IRQ disable byIRQMask = inportb(0x21); outportb(0x21, byIRQMask \| (1 << m_nIRQ)); //Modify Data Bit if(wDataBit < 5u \|\| wDataBit > 8u) { wDataBit = 8; } //Modify StartBit wStartBit = 1; //Modify StopBit if (wStopBit != ONESTOPBIT && wStopBit != ONE5STOPBITS && wStopBit != TWOSTOPBITS) { wStopBit = ONESTOPBIT; } //Save Comm Attrib pCommControl->nBase = nBase; pCommControl->dwBaud = dwBaud; pCommControl->wDataBit = wDataBit; pCommControl->wStartBit = wStartBit; pCommControl->wStopBit = wStopBit; pCommControl->wParity = wParity; m_bInterrupt = bInterrupt; //Write Baud outportb(nBase + COMM_REGISTER_LCR, 0x80); //baud-rate enable outportb(nBase + COMM_REGISTER_BAUDL, LOBYTE((115200L/ dwBaud))); outportb(nBase + COMM_REGISTER_BAUDH, HIBYTE((115200L/ dwBaud))); //Calc LCR Value BYTE byAttrib = 0u; if (wDataBit==5) {byAttrib &= ~(1<<1); byAttrib &= ~(1<<0);}//00 if (wDataBit==6) {byAttrib &= ~(1<<1); byAttrib \|= (1<<0);}//01 if (wDataBit==7) {byAttrib \|= (1<<1); byAttrib &= ~(1<<0);}//10 if (wDataBit==8) {byAttrib \|= (1<<1); byAttrib \|= (1<<0);}//11 if (wStopBit == ONESTOPBIT) byAttrib &= ~(1<<2); if (wStopBit == ONE5STOPBITS) byAttrib \|= (1<<2); if (wStopBit == TWOSTOPBITS) byAttrib \|= (1<<2); if (wParity == NOPARITY) { byAttrib &= ~(1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5); } else if(wParity == ODDPARITY) { byAttrib \|= (1<<3); byAttrib &= ~(1<<4); byAttrib &= ~(1<<5); } else if (wParity == EVENPARITY) { byAttrib \|= (1<<3); byAttrib \|= (1<<4); byAttrib &= ~(1<<5); } else if (wParity == MARKPARITY) { byAttrib \|= (1<<3); byAttrib &= ~(1<<4); byAttrib \|= (1<<5); } else if (wParity == SPACEPARITY) { byAttrib \|= (1<<3); byAttrib \|= (1<<4); byAttrib \|= (1<<5); } //write start bit, stop bit, parity outportb(nBase + COMM_REGISTER_LCR, byAttrib); //Moden control 00000110B outportb(nBase + COMM_REGISTER_MCR, 0x03); if (bInterrupt) { COMMCONTROL* pCommControl = this->GetCommControl(); this->CloseInterrupt(); m_bInterrupt = TRUE; asm pushf asm cli //Malloc buffer for read and write pCommControl->nIRQ = m_nIRQ; pCommControl->nBase = nBase; pCommControl->nErrorCode = COMM_ERROR_SUCCESS; pCommControl->pBufferR = new BYTE; pCommControl->pBufferS = new BYTE; pCommControl->nHeadR = pCommControl->nHeadS = 0; pCommControl->nTailR = pCommControl->nTailS = 0; pCommControl->nSizeR = pCommControl->nSizeS = COMM_INTERRUPT_BUFFER_SIZE; pCommControl->bFullR = pCommControl->bFullS = FALSE; asm cli //get old vect pCommControl->pOldFc = ::_dos_getvect(m_nIRQ + 8); //Set Interrupt Fc if (m_nIRQ == 3) { ::_dos_setvect(m_nIRQ + 8, CMotorNet_NewInterruptFc3); } else { ::_dos_setvect(m_nIRQ + 8, CMotorNet_NewInterruptFc4); } asm cli //Set IRQ Enable byIRQMask = inportb(0x21); outportb(0x21, byIRQMask & (~(1 << m_nIRQ))); //discard LSR inportb(nBase + COMM_REGISTER_LSR); //discard MSR inportb(nBase + COMM_REGISTER_MSR); //discard RBR inportb(nBase + COMM_REGISTER_RBR); //LCR Bit7->0 byAttrib = inportb(nBase + COMM_REGISTER_LCR); byAttrib &= 0x7F; outportb(nBase + COMM_REGISTER_LCR, byAttrib); //permit interrupt for receive data ,00000001B outportb(nBase + COMM_REGISTER_IER, 0x1); //Model control,00001100B outportb(nBase + COMM_REGISTER_MCR, 0xB); //FIFO control,00000000B outportb(nBase + COMM_REGISTER_FCR, 0x0); asm popf } } //中断模式时，用于清空输入缓冲区 void CMotorNet::ClearBufferR() { asm pushf asm cli COMMCONTROL* pCommControl = this->GetCommControl(); pCommControl->nHeadR = pCommControl->nTailR = 0; pCommControl->bFullR = FALSE; asm popf } //中断模式时，用于清空输出缓冲区 void CMotorNet::ClearBufferS() { asm pushf asm cli COMMCONTROL* pCommControl = this->GetCommControl(); pCommControl->nHeadS = pCommControl->nTailS = 0; pCommControl->bFullS = FALSE; asm popf } //判断是否有数据可读 BOOL CMotorNet::IsCommData() { COMMCONTROL* pCommControl = this->GetCommControl(); if (!m_bInterrupt) { return((inportb(pCommControl->nBase + COMM_REGISTER_LSR)&0x01)); } else { if (pCommControl->nHeadR != pCommControl->nTailR \|\| pCommControl->bFullR) { return (TRUE); } } return(FALSE); } //在规定的时间内等待数据的到来， BOOL CMotorNet::WaitCommData(DWORD dwWait) { DWORD far pdwMemoryTime = (DWORD far )MEMORY_TIME_ADDRESS; DWORD dwTime = pdwMemoryTime; //This maybe dead lock, you need modify code!!! while (!this->IsCommData())//(inportb(m_nCommBase+5) & 0x01)) { if (pdwMemoryTime - dwTime >= dwWait) { return(FALSE); } } return(TRUE); } //接收一个字节 BYTE CMotorNet::ReceiveData() { m_nErrorCode = COMM_ERROR_SUCCESS; if (!this->WaitCommData(COMM_TIME_DELAY)) { m_nErrorCode = COMM_ERROR_TIME; return(0); } COMMCONTROL* pCommControl = this->GetCommControl(); if (m_bInterrupt) { asm pushf asm cli BYTE byData = pCommControl->pBufferR; pCommControl->nHeadR = pCommControl->nHeadR + 1; if (pCommControl->nHeadR >= pCommControl->nSizeR) { pCommControl->nHeadR = 0; } pCommControl->bFullR = FALSE; asm popf return(byData); } else { return(inportb(pCommControl->nBase)); } } //发送一个字节 BOOL CMotorNet::SendData(BYTE nCh) { COMMCONTROL* pCommControl = this->GetCommControl(); if (!m_bInterrupt) { while (this->IsCommData()) { this->ReceiveData(); } DWORD far pdwMemoryTime=(DWORD far )MEMORY_TIME_ADDRESS; DWORD dwTime = pdwMemoryTime; //DWORD dwCount=0; while (!(inportb(pCommControl->nBase + COMM_REGISTER_LSR) & 0x20)) { if (pdwMemoryTime - dwTime > COMM_TIME_DELAY) //100 { m_nErrorCode = COMM_ERROR_TIME; return(FALSE); } } outportb(pCommControl->nBase,nCh); } else { if (pCommControl->bFullS) { return (FALSE); } asm pushf asm cli pCommControl->pBufferS = nCh; pCommControl->nTailS = pCommControl->nTailS + 1; if (pCommControl->nTailS >= pCommControl->nSizeS) { pCommControl->nTailS = 0; } if (pCommControl->nTailS == pCommControl->nHeadS) { pCommControl->bFullS = TRUE; } //permit interrupt for receive and send data ,00000011B outportb(pCommControl->nBase + COMM_REGISTER_IER, 0x3); asm popf } return(TRUE); } //接收多个字节 int CMotorNet::ReceiveBuffer(BYTE* pBuffer, int nCount, DWORD dwTimeOut) { for (int i = 0; i < nCount; i++) { if (!this->WaitCommData(dwTimeOut)) { return (i); } pBuffer = this->ReceiveData(); } return (nCount); } //发送多个字节 BOOL CMotorNet::SendBuffer(BYTE* pBuffer, int nCount) { for (int i = 0; i < nCount; i++) { if (!this->SendData(pBuffer)) { //在中断模式时，一直等到缓冲区不为空 if (m_bInterrupt && this->GetCommControl()->bFullS) { i--; continue; } return (FALSE); } } return (TRUE); } //判断总线是否忙 //常用于RS485发送端，一般情况下如果忙，须清空输入缓冲区 BOOL CMotorNet::IsBusy() { this->ClearLastCommError(); return (this->IsCommData()); }

第4楼　firstsail	发表于 2008-09-25 18:00
高级用户　发帖 295　积分 668　来自广东深圳
//此文件为WinSail V2.0下载后的“功能类_CMotorNet类串行通讯详细设计.DOC”文件 2 类简介类名为CMotorNet，头文件是“DownComm.h”。 3 类成员函数 3.1 IsCommData() 原型：BOOL IsCommData(); 作用：判断是否有数据可读入口参数：无出口参数：无返回值：有数据可读返回TRUE，否则返回FALSE。 3.2 IsBusy() 原型：BOOL IsBusy(); 作用：判断是否有数据可读,与IsCommData()函数作为相同入口参数：无出口参数：无返回值：有数据可读返回TRUE，否则返回FALSE。 3.3 WaitCommData() 原型：BOOL WaitCommData(DWORD dwWait); 作用：在指定的时间内等待有数据可读入口参数：DWORD dwWait ---- 时间计数值，以55mS为单位出口参数：无返回值：成功返回TRUE，否则返回FALSE 3.4 SendData() 原型：BOOL SendData(BYTE byCh); 作用：发送一个字节入口参数：BYTE byCh ---- 需发送的字节出口参数：无返回值：成功发送返回TRUE，否则返回FALSE 3.5 ReceiveData() 原型：BYTE ReceiveData(); 作用：接收一个字节入口参数：无出口参数：无返回值：成功返回数据值；否则返回0，并置通讯错误代码为COMM_ERROR_TIME 3.6 ReceiveBuffer() 原型：int ReceiveBuffer(BYTE* pBuffer, int nCount ,DWORD dwTimeOut = 0lu); 作用：接收多个字节入口参数： int nCount----------需读取的字节数 DWORD dwTimeOut-----超时时间，以55mS为单位出口参数：BYTE* pBuffer-------缓冲区首地址返回值：返回接收的字节数 3.7 Void SendBuffer() 原型：void Re(); 作用：发送多个字节入口参数：无出口参数：无返回值：无 3.8 Void ClearBufferR() 原型：void ClearBufferR(); 作用：在中断模式下，清除接收缓冲区入口参数：无出口参数：无返回值：无 3.9 Void ClearBufferS() 原型：void ClearBufferS(); 作用：在中断模式下，清除发送缓冲区入口参数：无出口参数：无返回值：无 3.10 ChangeParity() 原型：void ChangeParity(WORD wParity); 作用：修改奇偶校验属性入口参数：WORD wParity --- 奇偶校验属性，见InitComm()函数出口参数：无返回值：无 3.11 Void InitComm() 原型：void InitComm(int nBase, DWORD dwBaud, WORD wDataBit = 8, WORD wStartBit = 1, WORD wStopBit = 1, WORD wParityStyle = NOPARITY, BOOL bInterrupt = FALSE); 作用：初始化通迅口入口参数：int nBase --- 通讯口在基地址 COM1 = 0x3F8 COM2 = 0x2F8 COM3 = 0x3E8 COM4 = 0x2E8 DWORD dwBaud-----波特率，其值如下 CBR_50 50波特率 CBR_110 110波特率 CBR_300 300波特率 CBR_600 600波特率 CBR_1200 1200波特率 CBR_2400 2400波特率 CBR_4800 4800波特率 CBR_9600 9600波特率 CBR_14400 14400波特率 CBR_19200 19200波特率 CBR_38400 38400波特率 CBR_56000 56000波特率 CBR_57600 57600波特率 CBR_115200 115200波特率 CBR_128000 128000波特率 CBR_256000 256000波特率 WORD wDataBit---------数据位，值为5，6，7，8 WORD wStartBit--------起始位，值固定为“1” WORD wStopBit---------停止位，取值如下 ONESTOPBIT 1位停止位 ONE5STOPBITS 1.5位停止位 TWOSTOPBITS 2位停止位 WORD wParityStyle-----奇偶校验 NOPARITY 无校验 ODDPARITY 奇校验 EVENPARITY 偶校验 MARKPARITY 校验位永为“1” SPACEPARITY 校验位永为“0” BOOL bInterrupt-------中断模式，TRUE为中断模式，FALSE为查询模式出口参数：无返回值：无 3.12 int GetLastCommError() 原型：int GetLastCommError(); 作用：获得通讯错误代码入口参数：无出口参数：无返回值：通讯错误代码。如果没有通讯错误，返回COMM_ERROR_SUCCESS 3.13 void SetLastCommError () 原型：void SetLastCommError (int nErrorCode); 作用：设置通讯错误代码入口参数：int nErrorCode--------错误代码出口参数：无返回值：无 3.14 Void ClearLastCommError () 原型：int GetLastCommError(); 作用：清除通讯错误代码入口参数：无出口参数：无返回值：无 [ Last edited by firstsail on 2008-9-25 at 06:20 PM ]

第5楼　firstsail	发表于 2008-09-25 18:02
高级用户　发帖 295　积分 668　来自广东深圳
1.2 RS232的寄存器 RS232共有12个寄存器序号地址名称信号方向 1 Base + 0 发送保持寄存器只写 2 Base + 0 接收数据寄存器只读 3 Base + 0 除数锁存寄存器（LSB），波特率低八位可读写 4 Base + 1 除数锁存寄存器（MSB），波特率高八位可读写 5 Base + 1 IER----中断启用寄存器只读 6 Base + 2 IIR----中断标识寄存器只读 7 Base + 2 FCR----FIFO寄存器只写 8 Base + 3 LCR----线路控制寄存器可读写 9 Base + 4 MCR----MODEM控制寄存器可读写 10 Base + 5 LSR----线路状态寄存器只读 11 Base + 6 MSR----MODEM状态寄存器只读 12 Base + 7 暂时存储寄存器可读写 IER = base + 1, 中断启用寄存器 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \|_____允许接收数据就绪中断,置1时允许接收到数据时产生中断 \| \| \| \| \| \| \|_________允许发送保持器空中断,置1时允许发送保持寄存器空时产生中断 \| \| \| \| \| \|_____________允许接收线路状态中断，即置1时将在LSR变化时产生中断 \| \| \| \| \|_________________允许MODEM状态中断，即置1时将在MSR变化时产生中断 \| \| \| \|_____________________进入睡眠模式（16750） \| \| \|_________________________进入低功耗模式（16750） \| \|_____________________________未使用 \|_________________________________未使用 IIR = base + 2, 中断识别寄存器，只读属性 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \|_____指示是否有中断发生 \| \| \| \| \| \| \| 0:有中断发生 \| \| \| \| \| \| \| 1:无中断发生 \| \| \| \| \| \| \| \| \| \| \| \| \|___\_________标识具体的中断类型,中断具有优先级,LSR最高,MSR最低 \| \| \| \| \| 00:MODEL状态中断(CTS/RI/DTR/DCD) \| \| \| \| \| 01:发送保持寄存器空中断 \| \| \| \| \| 10:接收数据就绪中断 \| \| \| \| \| 11:接收线路状态中断 \| \| \| \| \|_________________超时中断(16550/16750) \| \| \| \|_____________________未使用 \| \| \|_________________________允许64字节FIFO(16550/16750) \| \| \|___\_____________________________00:无FIFO(此时是8250/16450芯片) 01:允许FIFO,但不可用 11:允许FIFO FCR = base + 2, FIFO控制寄存器，只写属性 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \|_____允许FIFO \| \| \| \| \| \| \|_________清除接收FIFO \| \| \| \| \| \|_____________清除发送FIFO \| \| \| \| \|_________________DMA模式选择 \| \| \| \|_____________________未使用 \| \| \|_________________________允许64字节FIFO \| \| \|___\_____________________________00:1Byte产生中断 01:4Byte产生中断 11:8Byte产生中断 11:14Byte产生中断 LCR = base + 3, 线路控制寄存器,可读/写 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \| \| \| \| \| \| \| \|___\_____00:5位数据位 \| \| \| \| \| \| 01:6位数据位 \| \| \| \| \| \| 10:7位数据位 \| \| \| \| \| \| 11:8位数据位 \| \| \| \| \| \|_____________0->1位停止位;1->2位停止位(6,7,8);1->1.5位停止位(5) \| \| \| \| \| \| \| \| \| \| \| \| \|___\___\_________________XX0:无校验 \| \| 001:奇校验 \| \| 011:偶校验 \| \| 101:奇偶保持为1 \| \| 111:奇偶保持为0 \| \|_____________________________设置间断，0-禁止，1-设置 \|_________________________________0:允许访问接收/发送及中断允许寄存器 1:允许访问波特率因子寄存器 MCR = base + 4, MODEM控制寄存器,可读/写 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \|_____设置DSR \| \| \| \| \| \| \|_________设置RTS \| \| \| \| \| \|_____________辅助输出1 \| \| \| \| \|_________________辅助输出2 \| \| \| \|_____________________环路测试 \| \| \|_________________________自动流量控制（仅16750） \| \|_____________________________未使用 \|_________________________________未使用 LSR = base + 5, 线路状态寄存器,只读 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \|_____接收数据就绪 \| \| \| \| \| \| \|_________超越错 \| \| \| \| \| \|_____________奇偶错 \| \| \| \| \|_________________帧格式错 \| \| \| \|_____________________间断 \| \| \|_________________________发送保持寄存器空 \| \|_____________________________发送移位寄存器空 \|_________________________________FIFO中接收数据错误 MSR = base + 6, MODEM状态寄存器,只读 B7, B6, B5, B4, B3, B2, B1, B0 \| \| \| \| \| \| \| \|_____CTS已改变 \| \| \| \| \| \| \|_________DSR已改变 \| \| \| \| \| \|_____________RI已改变 \| \| \| \| \|_________________DCD已改变 \| \| \| \|_____________________CTS有效 \| \| \|_________________________DSR准备就绪 \| \|_____________________________响铃指示 \|_________________________________载波检测 1.3 波特率的计算是用1.8432MHz时钟经过16分频的时钟（115200Hz）作为被除数，波特率作为除数，余数写入除数锁存寄存器中。 BYTE wDivL = LOBYTE(115200L/(DWORD)wBaud); BYTE wDivH = HIBYTE(115200L/ (DWORD)wBaud);

第6楼　firstsail	发表于 2008-09-25 18:24
高级用户　发帖 295　积分 668　来自广东深圳
DOS系统最多支持4个通讯口，分别为COM1、COM2、COM3、COM4。基地址分别对应于0x3F8、0x2F8、0x3E8、0x2E8。 RS232电缆一般是DB25或DB9物理接口，其意义如下： DB25 DB9 信号名称方向含义 2 3 TXD 输出数据发送端 3 2 RXD 输入数据接收端 4 7 RTS 输出请求发送（计算机要求发送数据）,低电平有效 5 8 CTS 输入清除发送（MODEM准备接收数据）,低电平有效 6 6 DSR 输入数据设备准备就绪,低电平有效 7 5 GND 信号地 8 1 DCD 输入数据载波检测,低电平有效 20 4 DTR 输出数据终端准备就绪（计算机）,低电平有效 22 9 RI 输入响铃指示在RS323电缆中，随着电缆长度的增加，信号遇到的电容就越多，从而使得数据的高速传输变得不可靠。并不是说在通讯时所有的管脚都被用上，这依赖于软件设计，但最简单的采用三线互联，RXD<—>TXD、TXD<—>RXD，GND<-->GND。

第7楼　lonm	发表于 2009-09-18 12:45
新手上路　发帖 6　积分 12
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第8楼　netreg	发表于 2009-11-16 17:46
初级用户　发帖 17　积分 134
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