Saturn SH-2 supports 16mb mem, ram upgrade

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I remember when I popped the hood on my Sophia (no I didnt completely dismantle or break it!) there were additional RAM slots so who knows.

With the RAM project I had in mind for the Sega Dreamcast, due to address multiplexing and other gubbins I can probably only fit 32MB onto the Sega Dreamcast without causing too many problems and even then I'd have to remap 3 pins and drill into the back of the SH-4 to make it work. There may be problems on games coded to the metal, but I think at least the WinCE games should be happy as they seem to use the MMU but hopefully more support it via the address mapping too. You may find similar address pin and multiplexing issues or other problems with the SH-2 too.

I don't have a Sega Saturn, the money or even the time to experiment on a second project. It is hard enough to afford the Sega Dreamcast project with other big expenses on the way, especially as I am on a limited budget. I'm also having to relearn old things I have forgotten and try to remember new things and purchases tools just to pull it off. I'll get there in the end but other people could do it much quicker

I wish you the best of luck and if you don't stay the course, I hope you will at least inspire someone else to finish the job!

 

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And a bump, bump, BOOM!

I've been having a dig while trying to work out what the SIMMCART switch does on the Sophia using this manual here.
For my controls I was using;
4MB Cart - X-Men Vs. Street Fighter
1MB Cart - The King of Fighters '96
and was going to use Pia Carrot he Youkoso!! 2 for seeing what was recognised automatically by the Sophia if I had say, 8MB of RAM installed.

Sadly X-Men Vs. Street Fighter and The King of Fighters '96 gave me nothing but error screens.
Interestingly though, when swapping back to my Action Replay Plus (includes 4M memory card, 1M / 4M expansion RAM card, region-free and Action Replay) it would not recognise it as a valid RAM cart either. There's no switches on this cart and it is supposed to be auto... then again I should pickup some of the real RAM carts for my collection anyway. So we'll call it a work in progress.

Should probably mention that as well.
When the SIMMCART switch in bank SW2 is ON the cartridge slot is ignored, presumably using the RAM in the SIMM slots. Can anyone confirm this?
When the SIMMCART switch is OFF, the Sophia will happily boot up to the Action Replay.

I am quite curious as to how, with the default 8MB of RAM installed, the games would address additional RAM.
I've read that a few games give graphical distortion when used with a 4MB cart when they required only a 1MB cart.
Would the games simply ignore the RAM?
Pia Carrot he Youkoso!! 2 may or may not show a different title screen depending on how much RAM is installed. Source here.

Although from the manual (Document ST-174-R2-090294.pdf) it reads....

That sounds like a RAM cartridge replacement to me, right?

I guess I should test the above mentioned games on a retail Saturn to make sure either, my Action Replay is a piece of junk... or that something else is not quite right...

 

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Excellent, One thing I did notice with the Action Replay Plus is that on the not-licensed-by-Sega screen there was some garbage / white blocks showing which I did not see on the retail Saturn. Although additionally the Action Replay Plus didn't work with X-Men Vs. Street Fighter on the retail Saturn at all. KoF '96 did work though and looked spectacular through the XRGB I might add!

Very interesting either way and thanks for the clarification as always. Know of any prototype / beta games I could try?
I mean all of these Sophias shipped with 8MB of RAM, surely one developer somewhere had utilised all available RAM before optimising code right?

 

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Ah yes, good old cartdev! I'd invest in one of them if only they were a bit larger.
Dev hardware needs to be at least two, preferably three times the size of final retail hardware as far as I am concerned! :wink-new:

 

... that's depends on the purpose.
for hardware dev yes you need biggest one with ample space but for software dev you really don't need and preferably close to retail version to test me think....