T-Unit conversions. Not possible

[gargamel]

Hi

I have two MK2 PCB lying around.
As you know, later revisions of MK1 use T-unit based hardware(MK2, NBA JAM TE, etc) and i want to downgrade one of the MK2 PCB to MK1 T unit 5.0.

i found this link talking about T-unit hardware.
http://www.vm68.com/mkromhacks/mk_t-unit.html"

How could i downgrade my MK2 pcb to MK1 T-unit 5.0?
I imagine this is just a question of reburning eproms, right?

Any advice are welcome

[invzim]

I vote a big fat MAYBE
mame/maws has some good info, also in the source:
http://maws.mameworld.info/maws/"

If you have en eprom writer handy, just trying wouldn't hurt.

[idc]

On a related note, this reminds me... I've often wondered if NBA Jam can be upgraded to TE with just a ROM swap...

[gargamel]

Ok.

I made some researches and found mk1 t-unit manual and will answer my question myself.
You can downgrade MK2 to MK1 T unit 5.0 by rewritting Eprom on T-unit CPU board.
But, unfortunately, MK2 use a specific Sound board with DCS chip. So you can play MK1 but without sound.
I imagine you can convert any T-unit game to an another as long they use same sound board.

Upgrading NBA jam to NBA jam TE maybe possible. I found a cheap working nba jam on Yahoo auction, i will test if it can be converted to something else.

[RetroRepair]

Upgrading NBA jam to NBA jam TE maybe possible

IIRC, T.E., like UMK3, were in fact eprom upgrades to existing NBA Jam and MK3 boards respectively.

Probably can't change the games completely though due to PAL differences. Would be an interesting experiment though.

[gargamel]

I know that you can convert M3/UMK3 PCB to Wrestle mania.

I will give a try, and report the result later.

[gargamel]

Upgrading NBA jam to NBA jam TE maybe possible

IIRC, T.E., like UMK3, were in fact eprom upgrades to existing NBA Jam and MK3 boards respectively.

Probably can't change the games completely though due to PAL differences. Would be an interesting experiment though.

You were right, pal chip prevent conversion. The game won t just boot..

UPDATE:I received yesterday my T-unit NBA JAM board.
i swapped nba jam boot eproms with MK boot eprom (respectively UJ12 and UG12) for testing.
Was very surprised The Board booted properly and rom check was of ok for UJ12 and UG12. . I just need now to burn graphic and sound eproms.
I tried to do the same with one of my MK2 board by swapping MK 1 and MK 2 boot rom., didn t work. the game keep rebooting on the coloured garbarge screen before the test rom check screen. It like something is preventing it to going further.

I cannot figure out why. because NBA JAM and my MK2 t-unit CPU board are almost identical..PAL chip??


So far,

NBA JAM T-Unit ===> MK 5.0 T-UNIT ○　(Rom check ok)
NBA JAM T-Unit ===> NBA JAM TE 　 ?　(Not tested but should be ok)
MK2 T-Unit ===> MK 5.0 T-_Unit X　 (endless rebooting)

Will continue my T-unit experimentations

[gargamel]

Ok some update.. but bad results.

I burned yesterday remaining MK and NBAJ TE graphics and sound eproms to complete the test.
Unfortunately, things did not work as expected.

I told you yesterday that in game eprom check was good for boot eprom (MK UJ12 and UG12 OK).
In game Eprom check was ok also for graphics and sound roms (all green).game could boot, and i can start a game but!...

Some weird things happened. (Believe it or not)
In MK (MK eproms on NBAJ T-unit PCB)

-when you selected your character and win the first round, at the second round, stamina bar of both fighter is drained and DRAW game! It does that for the remaining rounds then game over. .

Sometime, you start a game, and both fighter stamina are on danger on first round, then on the second, third, final round stamina drained with draw game until game over.

So the game is unplayable.

For NBA JAM TE,

Same scenario with in game rom check (all is fine).
But, when the game start, half bottom of the screen is garbage (you can see the court), if you start a game, it freeze then reboot.

I reburned the same eproms to standard NBA jam and it worked properly.

So,3 possibilities:

-PAL chip protection with some jackass behavior that tell you "Conversion=FAIL!HAHA, I win.."
-Bad eprom or bad burn?(I used same eprom to reburn NBAJAM and all was fine)
-Bad rom dumps.

Any advice?

[idc]

For NBA JAM TE,

Same scenario with in game rom check (all is fine).
But, when the game start, half bottom of the screen is garbage (you can see the court), if you start a game, it freeze then reboot.

I reburned the same eproms to standard NBA jam and it worked properly.

I can confirm that this behaviour is reproducible in MAME, when renaming ROM dumps from nbajamte.zip to their nbajam.zip counterparts.

Some images are in fact common between the two versions.

There was definitely an official TE upgrade kit for standard NBA Jam boards, so it must be something trivial.

[ropavann]

Ok some update.. but bad results.

I burned yesterday remaining MK and NBAJ TE graphics and sound eproms to complete the test.
Unfortunately, things did not work as expected.

I told you yesterday that in game eprom check was good for boot eprom (MK UJ12 and UG12 OK).
In game Eprom check was ok also for graphics and sound roms (all green).game could boot, and i can start a game but!...

Some weird things happened. (Believe it or not)
In MK (MK eproms on NBAJ T-unit PCB)

-when you selected your character and win the first round, at the second round, stamina bar of both fighter is drained and DRAW game! It does that for the remaining rounds then game over. .

Sometime, you start a game, and both fighter stamina are on danger on first round, then on the second, third, final round stamina drained with draw game until game over.

So the game is unplayable.

For NBA JAM TE,

Same scenario with in game rom check (all is fine).
But, when the game start, half bottom of the screen is garbage (you can see the court), if you start a game, it freeze then reboot.

I reburned the same eproms to standard NBA jam and it worked properly.

So,3 possibilities:

-PAL chip protection with some jackass behavior that tell you "Conversion=FAIL!HAHA, I win.."
-Bad eprom or bad burn?(I used same eprom to reburn NBAJAM and all was fine)
-Bad rom dumps.

Any advice?

Hello, how are you!
I'm having this same problem, you got it resolved.
It would help a lot
Thank you

[nem]

There was definitely an official TE upgrade kit for standard NBA Jam boards, so it must be something trivial.

Probably well known at this point, but the upgrade kit also had a replacement chip for UF5.

nba_jam_te_rom_kit.jpg

Anyway, I have a MK2 with the same issues as the NBA JAM conversion above (life bar goes down to nothing, draw game, etc). Didn't think it was a conversion initially, but maybe I need to give it a better look.