Re-align the Datassette playhead as it counts the
data pulses on the tape.
As the
faulty Datassette may not load the program to start with, one decent method is
to load the program using another working C2N and then hot-swap the devices
when it is time to re-calibrate. Although it is not recommended to hot-swap
Commodore devices, doing so with the cassette decks will not crash the computer
and is the most convenient way of loading the test program before the clock
pulses can be run.