通讯编程

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TModbus.cpp：源码内容

							//---------------------------------------------------------------------------
#include <vcl.h>
#pragma hdrstop
#include "TModbus.h"
#include "DMT.h"
#include "winsock2.h"
#pragma comment(lib, "ws2_32.lib")
#pragma comment(lib, "DMT.lib")
//---------------------------------------------------------------------------
#pragma package(smart_init)
#pragma resource "*.dfm"
TForm1 *Form1;
//---------------------------------------------------------------------------
__fastcall TForm1::TForm1(TComponent* Owner)
        : TForm(Owner)
{
     comm_type = 0;               // 通讯种类, 0:序列埠, 1:以太网络
     conn_num = 1;                 // 序列埠编号或联机识别码
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button1Click(TObject *Sender)
{
   OpenModbusSerial(1,9600, 8, 'N', 1, 2);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button2Click(TObject *Sender)
{
    CloseSerial(1);        
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Button3Click(TObject *Sender)
{
    modbus_addr = 0x01;           // 站号, 0
    modbus_func = 0x03;            // 功能码, 0x05
    sendbuf[0] = 0x00;             // Modbus起始地址, 0500
    sendbuf[1] = 0x00;
    sendbuf[2] = 0x00;          // Coil状态值 , FF00 / 0000  force coil on / off
    sendbuf[3] = 0x70;
    datalen = 4;                                                                         // Buffer数据长度 (bytes), ex: “0500FF00”
    RequestData(0,1,modbus_addr,modbus_func,sendbuf,datalen);
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Timer1Timer(TObject *Sender)
{
  AnsiString s = "接收:<-";
  int b = ResponseData(0,1,&modbus_addr,&modbus_func,recvbuf);
  Edit1->Text = b;
  if(b>0)
  {
     s +=IntToHex(modbus_addr,2)+" "+ IntToHex(modbus_func,2)+" "+ IntToHex(b,2)+ " ";
     for(int j = 0;j<b;j++)
     {
       s += IntToHex(recvbuf[j],2)+ " ";
     }
     Memo1->Lines->Add(s);
  }
}
//---------------------------------------------------------------------------
void __fastcall TForm1::Timer2Timer(TObject *Sender)
{
  Button3Click(NULL);
}
//---------------------------------------------------------------------------

						