Official: CPS1 (CPS1.5) Multi by Darksoft/Apocalypse - Interest Check Thread

[brizzo]

Selectable clock frequency isn't much of a problem to solve, way bigger engineering challenges for creating a CPS1 multi

Personally I would just use two oscillators with enable pins, and a couple AND gates and that's all thats needed. Or if the multi has a fpga, just have it output selectable clock, easy peasy

 

[nam9]

So yeah, the multi would just need to be tied into that pin and set it low or high based on which frequency the particular game needed.

Given that essentially you want to run all games at 12MHz (to reduce slowdown) with the exception of 10MHz only (where doing so would cause glitches), I guess it could be as simple as loading roms into a "1oMHz" & "12MHz" directory on SD, have the multi take that into consideration and tie S0 accordingly...

 

[rtw]

Or simpler, if we connect a wire from the DFO to a GPIO on the multi and if the file: 10Mhz or the file 12MHz exists in the game directory the signal is asserted accordingly.

 

[undamned]

Or simpler, if we connect a wire from the DFO to a GPIO on the multi and if the file: 10Mhz or the file 12MHz exists in the game directory the signal is asserted accordingly.

Yeah, I'm not sure why people are so fixated on this aspect.
-ud

 

[jassin000]

Yeah, I'm not sure why people are so fixated on this aspect.

I wouldn't say "fixated" but concerned, as last I knew we had reports that all games worked correctly on 12mhz A-boards.
Now it appears we need both clock speeds for true compatibility.

 

[undamned]

I think I mentioned this elsewhere (perhaps earlier in this very thread, lol) my Forgotten Worlds definitely run abnormally fast on my 12Mhz A board. So, yeah, I think those claiming 12Mhz for everything haven't actually tested everything, lol.
-ud

 

[jassin000]

I know with my CPS1 conversions, if the original game used a 10mhz A-board I used a 10mhz A-board.
I always suspected some issues might exist, but never actually tested anything.

I also tried to match long/short boards just for that complete look early on...
But long A-boards don't fit inside the Vewlix as well, so I ditched 'em for shorts.

 

[twistedsymphony]

I think I mentioned this elsewhere (perhaps earlier in this very thread, lol)

You did.
The whole 10mhz/12mhz was put to rest weeks back in March when you and a few others confirmed that some games don't run properly on 12MHz boards, and Apocalypse suggested that it would be simple to run two oscs and switch between them:

Just tested few more games on a DASH motherboard and found 1941 plays overspeed.
It obviously means a multi would need two different A boards (10MHz and 12MHz) to play games correctly OR a way has to be found to switch between the two frequencies (by modding the A board to accept an external CPU clock for instance).

I don't know why this is suddenly an issue again, maybe people weren't paying attention the first time?

 

[jassin000]

I don't know why this is suddenly an issue again, maybe people weren't paying attention the first time?

Yea I totally missed those posts, last I knew Apocalypse said everything was cool on 12mhz.

 

[ShootTheCore]

I think I mentioned this elsewhere (perhaps earlier in this very thread, lol) my Forgotten Worlds definitely run abnormally fast on my 12Mhz A board. So, yeah, I think those claiming 12Mhz for everything haven't actually tested everything, lol.
-ud

Strange, because I have Forgotten Worlds running perfectly fine on a 12mhz A board. That said, mine is a conversion with code Apocalypse added so I can use joystick buttons to rotate the character though. Maybe there's other code there to handle 12mhz correctly - I dunno.

 

[undamned]

I think I mentioned this elsewhere (perhaps earlier in this very thread, lol) my Forgotten Worlds definitely run abnormally fast on my 12Mhz A board. So, yeah, I think those claiming 12Mhz for everything haven't actually tested everything, lol.
-ud

Strange, because I have Forgotten Worlds running perfectly fine on a 12mhz A board. That said, mine is a conversion with code Apocalypse added so I can use joystick buttons to rotate the character though. Maybe there's other code there to handle 12mhz correctly - I dunno.

You've done an A-B test (play for a while on 10Mhz, then switch over to 12Mhz and play for a while? I'm not saying it was unplayable at 12Mhz, but if you are familiar with how it's supposed to run, it was noticeable.
-ud

 

[ShootTheCore]

You've done an A-B test (play for a while on 10Mhz, then switch over to 12Mhz and play for a while? I'm not saying it was unplayable at 12Mhz, but if you are familiar with how it's supposed to run, it was noticeable.-ud

I don't have any 10Mhz A boards so I can't do an A-B test, but I've played Forgotten Realms a lot on Mame (and the PC Engine port as well), and haven't noticed any glitches or differences. What differences did you see in your testing?

 

[ShootTheCore]

Also, I'm curious about how the @lydz and @aje_fr CPS Multi solutions both handle 1941 and Forgotten Worlds. Do those games run glitched, or has the game code been modified for 12Mhz compatibility?

 

[undamned]

You've done an A-B test (play for a while on 10Mhz, then switch over to 12Mhz and play for a while? I'm not saying it was unplayable at 12Mhz, but if you are familiar with how it's supposed to run, it was noticeable.-ud

I don't have any 10Mhz A boards so I can't do an A-B test, but I've played Forgotten Realms a lot on Mame (and the PC Engine port as well), and haven't noticed any glitches or differences. What differences did you see in your testing?

It's not a question of glitchiness. It's a speed difference. The 12Mhz runs ~17% faster than 10Mhz. I noticed this probably 10 years ago when I had a problem with my original Forgotten Worlds A board and swapped it for my Hyper Fighting A board. I was sad that it ran noticeably faster than the original.
-ud

 

[opt2not]

I don't know why this is suddenly an issue again, maybe people weren't paying attention the first time?

Yea I totally missed those posts, last I knew Apocalypse said everything was cool on 12mhz.

Same here. I also went ahead and upgraded my CPS1 board from 10 to 12mhz in anticipation of the multi. I guess that was premature.
I hope there is a elegant solution to supporting all games on the one board, something that’s cost and performance effective.

 

[Derick2k]

my original Forgotten Worlds

So when are you making those repro FW spinners, I need 2, just saying

 

[jassin000]

FW spinners, I need 2

If you've got $4K (to burn) I think YJA can hook you up.

 

[Derick2k]

FW spinners, I need 2

If you've got $4K (to burn) I think YJA can hook you up.

No need waiting on UD repro spinners

 

[undamned]

my original Forgotten Worlds

So when are you making those repro FW spinners, I need 2, just saying

Looking at my current project load, I don't know if it will ever happen. It looks like it would be a load of fun to shake out, though
-ud

 

[Porthos]

I would buy one, no doubt.