TApxComPort.OnTriggerLineError

TApxComPort

property OnTriggerLineError : TTriggerLineErrorEvent
TTriggerLineErrorEvent = procedure(
  CP : TObject; Error : Word; LineBreak : Boolean) of object;

Defines an event handler that is called whenever the dispatcher detects a line error or line break in the received data.

This event handler is called in a subset of the cases where the more general OnTriggerStatus handler is called. OnTriggerStatus is called first when a line error is detected, even if an OnTriggerLineError handler is installed.

CP is the TApxComPort component that generated the trigger. Error is a numeric code that indicates the most severe line error detected. See the LineError property for details. The LineBreak parameter is True if a line break was detected.

Note that status triggers are not self-restarting. The event handler must call SetStatusTrigger again to reactivate the trigger as needed.

The following example adds a status trigger for line errors and line breaks. The events are handled using an OnTriggerLineError event handler.

TrigLE : Word;
...
TrigLE := ApxComPort.AddStatusTrigger(stLine);
ApxComPort.SetStatusTrigger(TrigLE, lsParity or lsFraming or lsOverrun or lsBreak, True);
...
procedure TMyForm.ApxComPortTriggerLineError(
  CP : TObject; Error : Word; LineBreak : Boolean);
begin
  if Error <> leNone then
    ...process line error
  if LineBreak then
    ...process line break
  {reactivate trigger}
  ApxComPort1.SetStatusTrigger(TrigLE, lsParity or lsFraming or lsOverrun or lsBreak, True);
end;

See also: LineError, OnTriggerStatus, SetStatusTrigger