Hardware test

System ROM functionality. Navigate through screens by pressing start. Quit by resetting the system.

Crosshatch

See Crosshatch.

Color test

Can help diagnose color issues.

I/O test

Allows to check joypad inputs, hardware DIPs, test and service buttons, the marquee and credits displays.

Warning: the inputs are active low. Ground = "1" = pressed.

Sound test

Plays an intermittent 524Hz tone on the left, right or both speakers. Recording: File:Testbeep.zip

Memory card test

...

Backup clear

Press the A, B and C buttons at once to erase and format the backup RAM.

Calendar setup

See RTC.