I'm studying a bit how CPS2 B board works and so far I've understood what roms hold which and how the jumpers and PALs work.

Now I'm seeing that there are some "add-on" boards like those holding SIMMs and other ROMs such as the yellow rental carts and I'm intrigued about how they work.

MAME's sourcecode actually explains quite a lot but doesn't say exactly how each SIMM and ROMs match.

So, let's say we have Progear which has 4 SIMMs, each holing a certain amount of TSOP roms.

(for reference: progettoemma.net/gioco.php?game=progear )

Let's take for example SIMM 1 and 3 which hold the gfx data, splitted into 4 single roms, so we have:

simm.01a/b/c/d

simm.03a/b/c/d

We know GFX roms are located on sockets 13 to 20 on the main B board.

Now, we want to put the data from those SIMMs onto EPROMs on the main B Board, and here's where I'm stuck: where do we put what?

Is it just

simm.01a -> 13

simm.01b -> 14

etc... ?

Or is the data interleaved? I've seen Avalaunch ROMs uses only 4 EPROMs for gfx which means that he has combined two.

For reference, I'll leave the cps2 MAME driver here with all the relevant information: git.redump.net/mame/tree/src/mame/drivers/cps2.cpp

Thanks to all those who'll want to contribute!

EDIT: after some more research, I've found out that Artemio has made a utility to convert CPS2 EPROM data to put it into the SIMMs through a CPS-3 and darksoft's utility, so there definitely exist a correlation between the two. I've also found a user in this forum which has used this method to put Street Fighter Alpha 3 on the SIMMS of his Black CPS2 board, so it's definitely possible to do EPROM -> SIMM, which leads me to think that it must be possible to do the opposite.

Now I'm seeing that there are some "add-on" boards like those holding SIMMs and other ROMs such as the yellow rental carts and I'm intrigued about how they work.

MAME's sourcecode actually explains quite a lot but doesn't say exactly how each SIMM and ROMs match.

So, let's say we have Progear which has 4 SIMMs, each holing a certain amount of TSOP roms.

(for reference: progettoemma.net/gioco.php?game=progear )

Let's take for example SIMM 1 and 3 which hold the gfx data, splitted into 4 single roms, so we have:

simm.01a/b/c/d

simm.03a/b/c/d

We know GFX roms are located on sockets 13 to 20 on the main B board.

Now, we want to put the data from those SIMMs onto EPROMs on the main B Board, and here's where I'm stuck: where do we put what?

Is it just

simm.01a -> 13

simm.01b -> 14

etc... ?

Or is the data interleaved? I've seen Avalaunch ROMs uses only 4 EPROMs for gfx which means that he has combined two.

For reference, I'll leave the cps2 MAME driver here with all the relevant information: git.redump.net/mame/tree/src/mame/drivers/cps2.cpp

Thanks to all those who'll want to contribute!

EDIT: after some more research, I've found out that Artemio has made a utility to convert CPS2 EPROM data to put it into the SIMMs through a CPS-3 and darksoft's utility, so there definitely exist a correlation between the two. I've also found a user in this forum which has used this method to put Street Fighter Alpha 3 on the SIMMS of his Black CPS2 board, so it's definitely possible to do EPROM -> SIMM, which leads me to think that it must be possible to do the opposite.

The post was edited 2 times, last by donluca: Additional info ().