System self-test

Todo: Order of checks.

=Cartridge systems=

Some information by Channelmaniac.

The AES home console only performs checks when no game is detected.

MVS checks
Additionnal checks are performed on MVS systems. The SP-S2 system ROM does them in the following order:


 * 1) Work RAM
 * 2) Backup RAM
 * 3) Palette RAM bank 0
 * 4) Palette RAM bank 1
 * 5) Low VRAM
 * 6) High VRAM
 * 7) RTC
 * 8) System ROM checksum
 * 9) Z80

When a MVS board is powered up without cartridges inserted, the border color around the edges of the crosshatch screen indicates the system ROM region:


 * Red: Japanese, SPJ2
 * Cyan: USA, SPU2
 * Blue: Korean/Spanish, SPS2
 * Yellow: European
 * Green: 6 slot (ROM name ?)

=UniBios tests=

The Universe BIOS does not use the above color codes to indicate errors.