Bytes aus Comport lesen

[giantdwarf]

Hallo zusammen,

mithilfe der ComPort Library versuche ich gerade einen Kommunikation per ccTALK Protokoll mit dem COM Port aufzubauen (delphi2009).
Dafür schreibe ich einen einfachen Poll Befehl. Im OnRxCharEvent lese ich die ankommenden Bytes. Aber die Antwort stimmt nicht mit der Erwarteten überein.
Ich habe inzwischen erfahren, dass das Gerät immer die gesendeten Bytes als Echo zurückschickt und dann erst die eigentliche Antwort.
Ich erhalte aber immer nur 5 Bytes zurück, und das sind meines Erachtens nicht die gesendeten.
Hat irgendjemand eine Idee was ich falsch mache oder übersehen haben??

Delphi-Quellcode:

unit Unit1;

interface

uses
   Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
   Dialogs, CPort, StdCtrls;

type
   TForm1 = class(TForm)
      Button1: TButton;
      Memo1: TMemo;
      ComPort1: TComPort;
      procedure Button1Click(Sender: TObject);
      procedure ComPort1RxChar(Sender: TObject; Count: Integer);
      procedure FormClose(Sender: TObject; var Action: TCloseAction);
   private
      { Private-Deklarationen }
   public
      { Public-Deklarationen }
   end;

const   
   Binaer: array[0..255] of string = ('#0', '#1', '#2', '#3', '#4', '#5', '#6', '#7', '#8', '#9',
      '#10', '#11', '#12', '#13', '#14', '#15', '#16', '#17', '#18', '#19',
      '#20', '#21', '#22', '#23', '#24', '#25', '#26', '#27', '#28', '#29',
      '#30', '#31', '#32', '#33', '#34', '#35', '#36', '#37', '#38', '#39',
      '#40', '#41', '#42', '#43', '#44', '#45', '#46', '#47', '#48', '#49',
      '#50', '#51', '#52', '#53', '#54', '#55', '#56', '#57', '#58', '#59',
      '#60', '#61', '#62', '#63', '#64', '#65', '#66', '#67', '#68', '#69',
      '#70', '#71', '#72', '#73', '#74', '#75', '#76', '#77', '#78', '#79',
      '#80', '#81', '#82', '#83', '#84', '#85', '#86', '#87', '#88', '#89',
      '#90', '#91', '#92', '#93', '#94', '#95', '#96', '#97', '#98', '#99',
      '#100', '#101', '#102', '#103', '#104', '#105', '#106', '#107', '#108', '#109',
      '#110', '#111', '#112', '#113', '#114', '#115', '#116', '#117', '#118', '#119',
      '#120', '#121', '#122', '#123', '#124', '#125', '#126', '#127', '#128', '#129',
      '#130', '#131', '#132', '#133', '#134', '#135', '#136', '#137', '#138', '#139',
      '#140', '#141', '#142', '#143', '#144', '#145', '#146', '#147', '#148', '#149',
      '#150', '#151', '#152', '#153', '#154', '#155', '#156', '#157', '#158', '#159',                    

      '#160', '#161', '#162', '#163', '#164', '#165', '#166', '#167', '#168', '#169',
      '#170', '#171', '#172', '#173', '#174', '#175', '#176', '#177', '#178', '#179',
      '#180', '#181', '#182', '#183', '#184', '#185', '#186', '#187', '#188', '#189',
      '#190', '#191', '#192', '#193', '#194', '#195', '#196', '#197', '#198', '#199',
      '#200', '#201', '#202', '#203', '#204', '#205', '#206', '#207', '#208', '#209',
      '#210', '#211', '#212', '#213', '#214', '#215', '#216', '#217', '#218', '#219',
      '#220', '#221', '#222', '#223', '#224', '#225', '#226', '#227', '#228', '#229',
      '#230', '#231', '#232', '#233', '#234', '#235', '#236', '#237', '#238', '#239',
      '#240', '#241', '#242', '#243', '#244', '#245', '#246', '#247', '#248', '#249',
      '#250', '#251', '#252', '#253', '#254', '#255');
      
var                            
   Form1: TForm1;

implementation

{$R *.dfm}

procedure TForm1.Button1Click(Sender: TObject);
var
   Buff: array of Byte;
   i: Integer;
   sSend: String;

begin

   //ComPort initialisieren
   ComPort1.BaudRate := br9600;
   ComPort1.DataBits := dbEight;
   ComPort1.StopBits := sbOneStopBit;
   ComPort1.Parity.Bits := prNone;
   ComPort1.FlowControl.FlowControl := fcNone;
   ComPort1.Port := 'COM16';
   if not ComPort1.connected then
      ComPort1.Open;

   SetLength(Buff, 5);
   Buff[0] := 2;
   Buff[1] := 0;
   Buff[2] := 1;
   Buff[3] := 254;
   Buff[4] := 255;       //ccTalk Polling Befehl
   for i := 0 to 4 do
      sSend := sSend + Binaer[Buff[i]];
   Memo1.Lines.Clear;
   sSend := 'Sende: ' + sSend;
   Memo1.Lines.Add(sSend);

   //Befehl an Comport senden
   ComPort1.ClearBuffer(True, True); //sicherheitshalber
   ComPort1.Write(Buff, 5);

end;

procedure TForm1.ComPort1RxChar(Sender: TObject; Count: Integer);
var
   Buff: array of Byte;
   ComStream: TComStream;
   sReceive: String;
   i: Integer;
begin
   if Count > 0 then
   begin

      ComStream := TComStream.Create(ComPort1);
      try
         SetLength(Buff, Count);
         //Ankommende Bytes lesen
         ComStream.Read(Buff[0], Count);
         for i := 0 to Count-1 do
            sReceive := sReceive + Binaer[Buff[i]];
         sReceive := 'Lese: ' + sReceive;   
         Memo1.Lines.Add(sReceive);   
      finally       
         ComStream.Free;
      end;
   end;
   
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
   if ComPort1.Connected then
      ComPort1.Close;
end;

end.

Delphi-Quellcode:

  object ComPort1: TComPort
    BaudRate = br9600
    Port = 'COM1'
    Parity.Bits = prNone
    StopBits = sbOneStopBit
    DataBits = dbEight
    Events = [evRxChar, evTxEmpty, evRxFlag, evRing, evBreak, evCTS, evDSR, evError, evRLSD, evRx80Full]
    FlowControl.OutCTSFlow = False
    FlowControl.OutDSRFlow = False
    FlowControl.ControlDTR = dtrDisable
    FlowControl.ControlRTS = rtsDisable
    FlowControl.XonXoffOut = False
    FlowControl.XonXoffIn = False
    StoredProps = [spBasic]
    TriggersOnRxChar = True
    OnRxChar = ComPort1RxChar
    Left = 72
    Top = 104
  end