delphi串口读写台达plc

delphi串口读写台达plc PLC台达DELPHI通讯MODBUS procedure TfrmMain.btnReadMClick(Sender: TObject); var sStr:String; i:Integer; begin for i:= 0 to 1279 do Begin kmtPLC.SendData('0102'+IntToHex(i+$800,4)+'0001'); //取输出状态 sStr:=kmtPLC.ReadResFromPort(); if sStr'' then Begin memo1.Lines.Add('M'+IntToHex(i,4)+'-'+FormatFloat('0000',i)+'-'+Copy(sStr,1,Length(sStr)-2)); End; End; end; procedure TfrmMain.SpeedButton4Click(Sender: TObject); var sStr:String; begin kmtPLC.SendData('0103'+IntToHex(StrToInt(edtDAddr.Text)+$1000,4)+'0001'); sStr:=kmtPLC.ReadResFromPort(); if sStr'' then Begin edtDValue.Text:=sStr; End; end;