使用c++builder寫的串口通訊源代碼

本文為轉載文章

在网上很难找到C++串口通信的源码，因此我将刚做好的程序源码公开。当中如有bug,烦请告知，以便对学习者负责。此程序仅供串口初学者学习。
我已经在windows 2000下编译测试通过。因为此程序针对厂内一种仪表所编，请按自己情况修改。但核心部分是不需修改的。
界面右侧可以输入数字进行测试，注意最后请跟一个回车键，测试时将RS-232接口的第2，第3针连接，即可进行自发送，自接收。
可以随便转载，但请保持完整 --- masa。
程序中使用了windows API函数，unit2.h unit2.cpp为监视线程，没有窗口。

#########
//--------------unit.h-----------

#ifndef UnitH
#define UnitH
//-----------------------------------
#include <Classes.hpp>
#include <Controls.hpp>
#include <StdCtrls.hpp>
#include <Forms.hpp>
#include <ExtCtrls.hpp>
#include <Graphics.hpp>
#include <jpeg.hpp>
#include <ComCtrls.hpp>
#include <Grids.hpp>
#include <CheckLst.hpp>
//------------------------------------------------------------
class TForm1 : public TForm
{
__published: // IDE 管理のコンポーネント
TRadioGroup *RadioGroup1;
TButton *Button3;
TButton *Button4;
TButton *Button5;
TMemo *Memo2;
TLabel *Label2;
TImage *Image1;
TGroupBox *GroupBox1;
TEdit *Edit1;
TEdit *Edit2;
TLabel *Label3;
TLabel *Label4;
TLabel *Label12;
TComboBox *ComboBox3;
TLabel *Label7;
TLabeledEdit *LabeledEdit1;
TLabeledEdit *LabeledEdit2;
void __fastcall Button4Click(TObject *Sender);
void __fastcall Button3Click(TObject *Sender);
void __fastcall FormCreate(TObject *Sender);
void __fastcall Button5Click(TObject *Sender);
private:
public:
__fastcall TForm1(TComponent* Owner);
};
//---------------------------------------------------------------------------
extern PACKAGE TForm1 *Form1;
//---------------------------------------------------------------------------
#endif





##########
//-------------------unit.cpp---------------

#include <vcl.h>
#pragma hdrstop

#include "Unit.h"
#include "Unit2.h"
#include <vector>
#include <algorithm>
#include <string>

//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
HANDLE hCom;
hComWatchThread *Read232;

DCB dcb;
OVERLAPPED OverWrite;
OVERLAPPED OverRead;

String comname;
extern int x0,y0;
extern int x,y,test;
extern bool CanPaint;
extern double num;
extern std::vector<double>vec;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
: TForm(Owner)
{
}


//------ Create COM ----------------------------------------------------------
bool CreateCom(String comname)
{
if (hCom==INVALID_HANDLE_VALUE)
{
ShowMessage("You are using thd HANDLE hCom ,It will be reopen");
CloseHandle(hCom);
}

hCom=CreateFile( comname.c_str(),
GENERIC_READ|GENERIC_WRITE,
0,
NULL,
OPEN_EXISTING,
FILE_FLAG_OVERLAPPED,
NULL);
if (hCom==INVALID_HANDLE_VALUE)
{
ShowMessage("Can not open the port !");
CloseHandle(hCom);
hCom=0;
Form1->Caption=comname+" 通信失敗！別のポートを使用して下さい！";
return false;
}

if (!SetCommMask(hCom,EV_RXCHAR)) ShowMessage("SetCommMask failed");
if (!SetupComm(hCom,1024,1024)) ShowMessage("SetupComm failed");
PurgeComm(hCom,PURGE_TXABORT|PURGE_RXABORT|PURGE_TXCLEAR|PURGE_RXCLEAR);

GetCommState(hCom,&dcb);

dcb.BaudRate=2400;
dcb.fParity=0;
dcb.Parity=NOPARITY;
dcb.StopBits=ONESTOPBIT;
dcb.ByteSize=8;
dcb.fNull=FALSE;

SetCommState(hCom,&dcb);
ShowMessage(IntToStr(dcb.BaudRate) + " fParitu :" +
IntToStr(dcb.fParity) + " Parity :" +
IntToStr(dcb.Parity) + " ByteSize :" +
IntToStr(dcb.ByteSize) + " StopBits :" +
dcb.StopBits + " " + comname + " Open successed");

Form1->Caption=comname+" 通信成功！";
Form1->RadioGroup1->Enabled=false;
Form1->GroupBox1->Enabled=false;
Form1->Button3->Enabled=false;
Form1->Button4->Enabled=true;

Read232=new hComWatchThread(false); // (false/true) (run/not run )WatchThread when begin
Read232->FreeOnTerminate=true;

return true;
}



bool StopCom()
{
if (hCom) //Stop COM
{
if (CloseHandle(hCom))
{ ShowMessage("CloseHandle(hCom) successed");
Read232->Terminate();
}
else
{ ShowMessage("Can not close the com !!!");
return false;
}

Form1->RadioGroup1->Enabled=true;
Form1->Caption="通信停止中";
}
else ShowMessage("The com has been stoped !!");

hCom=0;
Form1->Button3->Enabled=true;
Form1->Button4->Enabled=false;
Form1->GroupBox1->Enabled=true;
return true;
}


//------333 Begin Read data From COM 3333333-------------------------------
void __fastcall TForm1::Button3Click(TObject *Sender)
{
if (RadioGroup1->ItemIndex==0) comname="COM1";
if (RadioGroup1->ItemIndex==1) comname="COM2";
if (RadioGroup1->ItemIndex==2) comname="COM3";
if (RadioGroup1->ItemIndex==3) comname="COM4";

if (CreateCom(comname)) //ShowMessage(Form1->ComboBox1->Items->operator [](0) );
{
x=x0;
test=0;
CanPaint=false;
num=0;

COMSTAT comstat;
DWORD dwError=0;
String dat;
DWORD bResult;
DWORD BytesRead;
OVERLAPPED OverRead;
OverRead.hEvent=CreateEvent(NULL,true,false,NULL);

ClearCommError(hCom,&dwError,&comstat) ;

if (hCom!=INVALID_HANDLE_VALUE)
{
bResult=ReadFile(hCom,
dat.c_str(),
comstat.cbInQue,
&BytesRead,
&OverRead);
if (!bResult && GetLastError()==ERROR_IO_PENDING)
ShowMessage("pending");

char s;
String str;
for (unsigned int i=0;i<comstat.cbInQue;i++)
{
s=*(dat.c_str()+i);
str=str+s;
}
}
Form1->Image1->Picture=0 ; //LoadFromFile("a.bmp");
Form1->Image1->Canvas->Pen->Color=clBlack;
Form1->Image1->Canvas->Pen->Width=1;
Form1->Image1->Canvas->MoveTo(x0,300) ;
Form1->Image1->Canvas->LineTo(x0,30); // Y axis
Form1->Image1->Canvas->Pen->Width=2;
Form1->Image1->Canvas->LineTo(x0,10); // Y Arrow

Form1->Image1->Canvas->Pen->Width=1;
Form1->Image1->Canvas->MoveTo(20,y0) ;
Form1->Image1->Canvas->LineTo(750,y0); // X axis
Form1->Image1->Canvas->Pen->Width=2;
Form1->Image1->Canvas->LineTo(770,y0); // X Arrow




Form1->Image1->Canvas->Pen->Width=1;
Form1->Image1->Canvas->Pen->Style=psDot;
int line=y0;
for (int cou=0; cou<7; cou++)
{
line=line-30;
if (cou==0 || cou>=5)
Form1->Image1->Canvas->Pen->Color=clRed;
else
Form1->Image1->Canvas->Pen->Color=clGreen;

Form1->Image1->Canvas->MoveTo(x0,line) ;
Form1->Image1->Canvas->LineTo(750,line);
}
}
}


//--------444 Write data to COM 444444---------------------------------------
void __fastcall TForm1::Button4Click(TObject *Sender)
{
BOOL WriteState;
AnsiString str=Form1->Memo2->Text;
unsigned long Written ;
DWORD dwError;
unsigned long StrLen=str.Length();

WriteState=WriteFile(hCom,str.c_str(),StrLen,&Written,&OverWrite);

if (!WriteState && GetLastError()==ERROR_IO_PENDING )
{
while (!GetOverlappedResult(hCom,&OverWrite,&StrLen,false))
{ dwError=GetLastError();
if (dwError==ERROR_IO_INCOMPLETE)
continue;
else
{ ShowMessage("Can not continue GetOverlappedResult()");
break;
}
}
}
else ShowMessage("データ転送失敗！通信状態を確認して下さい！");

}



//-------555 Memo Clear 5555--------------------------------------------------
void __fastcall TForm1::Button5Click(TObject *Sender)
{
StopCom();

if (vec.size()>100)
{
std::sort(vec.begin(),vec.end());
LabeledEdit1->Text=*(vec.end()-10);
Form1->LabeledEdit2->Text=*(vec.begin()+10);
}
vec.erase( vec.begin(),vec.end() );
}



//-------- Stop COM and Watch Thread -----------------------------------------
void __fastcall TForm1::FormCreate(TObject *Sender)
{
Form1->Button3->Enabled=true;
Form1->Button4->Enabled=false;
}



###########
//-----------------unit2.h------------------

#ifndef Unit2H
#define Unit2H
//---------------------------------------------------------------------------
#include <Classes.hpp>
//---------------------------------------------------------------------------
class hComWatchThread : public TThread
{
private:
protected:
void __fastcall WriteMemo();
void __fastcall Execute();
public:
__fastcall hComWatchThread(bool CreateSuspended);
};
//---------------------------------------------------------------------------
#endif




##########
//---------------------unit2.cpp---------------------

#include <vcl.h>
#pragma hdrstop

#include "Unit2.h"
#include "Unit.h"
#include <algorithim>

#include <string>
#include <vector>
#pragma package(smart_init)
//---------------------------------------------------------------------------


extern HANDLE hCom;
extern OVERLAPPED OverRead,OverWrite;
extern hComWatchThread *Read232;
extern StopCom();
int x0=50 , y0=270; //axis of coordinate

COMSTAT comstat;
OVERLAPPED os;
DWORD dwEvtMask=0;

AnsiString dat;
int test;

int x=x0 ;
bool CanPaint=false;
std::vector<double> vec;
double num;

__fastcall hComWatchThread::hComWatchThread(bool CreateSuspended)
: TThread(CreateSuspended)
{
}
//---------------------------------------------------------------------------


void __fastcall hComWatchThread::WriteMemo()
{
int y=y0-3*num;
Form1->Image1->Canvas->Pen->Color=clLime;
Form1->Image1->Canvas->Pen->Width=1;
Form1->Image1->Canvas->Pen->Style=psSolid;

if (x==x0)
Form1->Image1->Canvas->MoveTo(x,y);
else
Form1->Image1->Canvas->LineTo(x,y);

if ( num>StrToInt(Form1->Edit1->Text) || num<StrToInt(Form1->Edit2->Text) )
{ Form1->Image1->Canvas->Pen->Color=clRed;
Form1->Image1->Canvas->Brush->Color=clRed;
Form1->Image1->Canvas->Ellipse(x-2,y-2,x+2,y+2);
}
x=x+1;

if ((x-x0) > ((Form1->ComboBox3->ItemIndex)*5+20)*20 ) // when dcb.BaudRate=2400, 20次/秒 in my meter
{
ShowMessage("測定完了!");
x=x0;
CanPaint=false;
StopCom();

std::sort(vec.begin(),vec.end());
Form1->LabeledEdit1->Text=*(vec.end()-10);
Form1->LabeledEdit2->Text=*(vec.begin()+10);
vec.erase(vec.begin(),vec.end() );
}
}


void __fastcall hComWatchThread::Execute()
{
memset(&OverRead,0,sizeof(OVERLAPPED));
OverRead.hEvent=CreateEvent(NULL,true,true,NULL);
if (OverRead.hEvent==NULL) Terminate();

if (!SetCommMask(hCom,EV_RXCHAR|EV_TXEMPTY)) Terminate();

while (!Terminated)
{
WaitForSingleObject(OverRead.hEvent,INFINITE);

bool WaitComEv;
DWORD dwError;
AnsiString Gotstr;

DWORD ReadStat;
DWORD BytesRead;

WaitComEv=WaitCommEvent(hCom,&dwEvtMask,&OverRead);
if (WaitComEv)
ClearCommError(hCom,&dwError,&comstat);
else if (!WaitComEv && GetLastError()==ERROR_IO_PENDING)
{
ClearCommError(hCom,&dwError,&comstat);

while (comstat.cbInQue>0 && dwEvtMask==EV_RXCHAR)
{
AnsiString Getstr;
char *pt=Getstr.c_str();
ReadStat=ReadFile(hCom,Getstr.c_str(),comstat.cbInQue,&BytesRead,&os);

if (!ReadStat && GetLastError()==ERROR_IO_PENDING )
{
while (!GetOverlappedResult(hCom,&os,&BytesRead,true))
{
dwError=GetLastError();
if (dwError==ERROR_IO_INCOMPLETE)
continue;
else
break;
}
}

for (unsigned int i=0;i<comstat.cbInQue;i++)
{
dat=dat+pt[i];
if (pt[i]==''\n'')
{
AnsiString everyone;
char *p=dat.c_str();
for (int j=0; j<dat.Length()-2; j++)
everyone = everyone + p[j];
test++;

if (test>1) num=StrToFloat(everyone);
dat=NULL;

if (num>20 ) CanPaint=true;

if (CanPaint==true)
{ vec.push_back(num);
Synchronize(WriteMemo);
}
}
}

ClearCommError(hCom,&dwError,&comstat);
dwEvtMask=0;
}

}
}
}
//---------------------------------------------------------------------------