The XL has some debugging capabillities built in that utilize the DB9 serial port. This port is also used for barcode scanners. On powerup the XL tests the state of the CTS pin to detect if a PC or a Scanner is connected. When a PC is detected the controller has debug code that monitors the serial port for commands from the PC that will execute or enable debug code.

The input task was the task that was doing the monitoring. If the debug code took to long to execute it could cause the input task to miss petting the Watch dog for too long and the 0x000F0001 task error would occur.

This was fixed by moving the monitoring code to the Peg task (user interface) which a lower priority task than the Input task.