Habe das so gemacht, wie Wacheia es vorgeschlagen hat.

Es kommt nach einiger Zeit folgendes Fehler:

Timed Out waiting for: STB7100-REF> |ufs910>

Application version: 3.0.0.0
Operating system: Microsoft Windows NT 6.0.6001 Service Pack 1
.NET version: 2.0.50727.3074

Callstack:
bei KCC.SerialConnection.WaitFor(String dataToWaitFor, String breakCharacter) in d:\wintest\KCC\SerialConnection.cs:Zeile 167.
bei KCC.SerialConnection.SendAndWait(String message, String waitFor, String breakCharacter) in d:\wintest\KCC\SerialConnection.cs:Zeile 242.
bei KCC.AdvForm.btnStart_Click(Object sender, EventArgs e) in d:\wintest\KCC\AdvForm.cs:Zeile 394.
bei System.Windows.Forms.Control.OnClick(EventArgs e)
bei System.Windows.Forms.Button.OnMouseUp(MouseEventAr gs mevent)
bei System.Windows.Forms.Control.WmMouseUp(Message& m, MouseButtons button, Int32 clicks)
bei System.Windows.Forms.Control.WndProc(Message& m)
bei System.Windows.Forms.ButtonBase.WndProc(Message& m)
bei System.Windows.Forms.Button.WndProc(Message& m)
bei System.Windows.Forms.Control.ControlNativeWindow.W ndProc(Message& m)
bei System.Windows.Forms.NativeWindow.Callback(IntPtr hWnd, Int32 msg, IntPtr wparam, IntPtr lparam)

Last log entries:
20090312 193017 SERIAL: Received: [T]
20090312 193017 SERIAL: Received: [ ]
20090312 193022 SERIAL: Received: [T]
20090312 193022 SERIAL: Received: [ ]
20090312 193027 SERIAL: Received: [T]
20090312 193027 SERIAL: Received: [ ]
20090312 193032 SERIAL: Received: [T]
20090312 193032 SERIAL: Received: [ ]
20090312 193037 SERIAL: Received: [T]
20090312 193037 SERIAL: Received: [ ]
20090312 193042 SERIAL: Received: [T]
20090312 193042 SERIAL: Received: [ ]
20090312 193047 SERIAL: Received: [T ]
20090312 193052 SERIAL: Received: [T]
20090312 193052 SERIAL: Received: [ ]
20090312 193057 SERIAL: Received: [T]
20090312 193057 SERIAL: Received: [ ]
20090312 193102 SERIAL: Received: [T]
20090312 193102 SERIAL: Received: [ ]
20090312 193106 TELNET: Timed Out waiting for: [STB7100-REF> |ufs910> ]