System self-test: Difference between revisions

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AES and MVS [[system ROM]]s compute their own checksums and compare them against the 16bit value at address $000080. The checksum is a simple byte sum of the whole system ROM except locations $000080 and $000081.
Todo: Order of checks.


Checks order ?
=Cartridge systems=


=Cartridge systems=
Some information by Channelmaniac.


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


{|class="regdef"
{|class="regdef"
|'''Error'''
|No game
|[[WORK RAM ERROR]]
|[[COLOR RAM ERROR]]
|[[VIDEO RAM ERROR]]
|[[SYSTEM ROM ERROR]]
|[[MEMORY CARD ERROR]]
|-
|'''AES'''
|'''AES'''
|[[File:aes_sc_blue.png]]
|[[File:aes_sc_blue.png]]
Line 17: Line 25:
|-
|-
|'''MVS'''
|'''MVS'''
|[[Crosshatch]]
|[[File:crosshatch.png|160px]] [[Crosshatch]]
|WORK RAM ERROR
|[[File:error_wram.png|160px]]
|COLOR RAM BANK0/1 ERROR
|[[File:error_color0.png|160px]]
|VIDEO RAM ERROR ([[VRAM]])
|[[File:error_vram.png|160px]]
|SYSTEM ROM ERROR
|[[File:error_sysrom.png|160px]]
|MEMORY CARD ERROR
|Screenshot needed
|-
|-
|'''Meaning'''
|'''Meaning'''
|All tests passed (AES does not test the [[Z80]]). Cartridge not detected or not present.
|All tests passed (AES does not test the {{Chipname|Z80}}). Cartridge not detected.
|[[68k user RAM|Work RAM]] error ($100000 region)
|[[68k user RAM]] R/W error
|[[Palette RAM]] error ($400000 region)
|[[Palette RAM]] R/W error
|[[VRAM|Video RAM error]]
|[[VRAM]] R/W error
|[[system ROM error|System ROM checksum mismatch]] (0xC00000 region)
|[[system ROM error|System ROM checksum mismatch]]
|[[Memory card]] error (only tested if card present and blank)
|[[Memory card]] R/W error (only tested if card present and blank)
|}
|}


==The UniBios case==
==MVS checks==


The [[Universe BIOS]] does not use the above color codes to indicate errors.
Additionnal checks are performed on MVS systems. The SP-S2 [[system ROM]] does them in the following order:
 
# Work RAM
# Backup RAM
# Palette RAM bank 0
# Palette RAM bank 1
# Low VRAM
# High VRAM
# RTC
# System ROM checksum
# Z80


==MVS checks==
{|class="regdef"
|'''Error'''
|[[BACKUP RAM ERROR]]
|[[Calendar freeze]]
|[[CALENDAR ERROR]]
|[[Z80 ERROR]]
|-
|'''Display'''
|[[File:error_bram.png|160px]]
|[[File:calendar_freeze.png|160px]]
|[[File:error_calendar.png|160px]]
|[[File:error_z80.png|160px]]
|-
|'''Meaning'''
|[[Backup RAM]] R/W error
|[[RTC]] isn't giving Time Pulse
|[[RTC]] ran to slow or too fast
|[[Z80]] didn't reply to command
|}


Additionnal checks are performed on MVS systems:
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:


*Backup RAM: [[BACKUP RAM ERROR]] (Battery-backed RAM)
* Red: Japanese, SPJ2
*RTC chip: [[CALENDAR ERROR]]
* Cyan: USA, SPU2
*Z80: [[Z80 ERROR]]
* Blue: Korean/Spanish, SPS2
* Yellow: European
* Green: 6 slot (ROM name ?)


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


*Green: 6 slot (ROM name ?)
The [[Universe BIOS]] does not use the above color codes to indicate errors.
*Cyan: USA, SPU2
*Blue: Spanish, SPS2
*Red: Japanese, SPJ2


[[Category:Base system]]
[[Category:Base system]]
[[Category:Repairs]]

Latest revision as of 05:23, 8 November 2018

Todo: Order of checks.

Cartridge systems

Some information by Channelmaniac.

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

Error No game WORK RAM ERROR COLOR RAM ERROR VIDEO RAM ERROR SYSTEM ROM ERROR MEMORY CARD ERROR
AES
MVS Crosshatch Screenshot needed
Meaning All tests passed (AES does not test the Z80). Cartridge not detected. 68k user RAM R/W error Palette RAM R/W error VRAM R/W error System ROM checksum mismatch Memory card R/W error (only tested if card present and blank)

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
Error BACKUP RAM ERROR Calendar freeze CALENDAR ERROR Z80 ERROR
Display
Meaning Backup RAM R/W error RTC isn't giving Time Pulse RTC ran to slow or too fast Z80 didn't reply to command

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.