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Scheduling an ARINC Word

Open topic with navigation CAPL Functions » A429 » Scheduling an ARINC Word Valid for: CANoe DE • CANoe4SW DE An ARINC word may be transmitted either on request or cyclically (supported by the hardware scheduler). The transmission behavior is controlled via the selectors TxCtrl and TxCycle. The transmission of an ARINC word is initiated with the function output or a429Transmit. If a real hardware is used the ARINC word is transferred to the hardware with this call. Example: Schedule the Cyclic Transmission of an ARINC Word 
variables {
  a429Word LBL_103 myWord = {msgChannel = 1};
}

on start {
  myWord.SSM_103 = 3;
  output (myWord); // start scheduling
}

on key '+' {
  myWord.SelAirspeed.phys += 22.5;
  output(myWord); // update
}

on key '-' {
  myWord.SelAirspeed.phys -= 22.5;
  output(myWord); // update
}
If an ARINC word is initialized based on a message in a database, the cycle time is taken from the database attribute A429Cycle. For every ARINC word you may also modify the minimum distance to the previous sent ARINC word via the selector gap. Example: Transmit ARINC Words on Request 
variables {
  a429Word LBL_103 myWord = {msgChannel = 2};
  msTimer myTimer; // major schedule
}

on start {
  a429SetScheduleTx (myWord, 0); // erase cycle time
  myWord.SSM_103 = 3;
  setTimer (myTimer, 10); // fire up timer
}

on timer myTimer {
  int i;
  setTimer (myTimer, 10); // rearm timer
  // send 3 ARINC words with 40, 80 and 120 us gap
  for (i = 0; i < 3; i++)
  {
    a429SetGap (myWord, ((i * 40000) + 40000));
    myWord.SelAirspeed.phys += 22.5;
    output(myWord); // update
  }
}
If you want to schedule ARINC words with just the minimum allowed gap phase in between, you have to use the function a429Transmit.