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Actually, the 32Mb SIMMs have 2 x MBM29F016-90PFTR (Fujitsu 16Mb 90ns Reverse pinout) chips.

So, It is possible to convert an 32Mb SIMM into a 128Mb chip if you have 2 more MBM29F016-90PFTR AND 4 x MBM29F016-90PFTN (Fujitsu 16Mb 90ns Normal pinout) chips and optionally 6 x 100nF smt capacitors.

I've tried putting additional flash chips on a 32Mb SIMM without success because I was mix matching different vendor chips (Fujitsu, ST and AMD).

As Mitsurugi-w said, finding reverse pinout Fujitsu flash chips is almost impossible. BUT, if you have 2 x 32Mb SIMMs and 1 x 64Mb SIMM, you can use the PCB of one of the 32Mb SIMMs as a base and salvage the 2 reverse pinout flash ICs from the other 32Mb SIMM and 4 normal pinout ICs from the 64Mb SIMM.

You have to be skilled in surface mount desoldering and soldering though...
Yes, that's right. At least for me the 32Mb SIMMs I have, they come with reversed.
You could eventually use 64Mb to make a 128Mb bigger SIMM.
 
What about the possibility of fixing faulty simms?

I've got a 128M which won't flash, I suspect one of the chips has failed, I also have a 32M & 64M simm spare - could one working 128M be made out of that combination?

Would it be feasible to offer a simm rebuild service?
 
What about the possibility of fixing faulty simms?

I've got a 128M which won't flash, I suspect one of the chips has failed, I also have a 32M & 64M simm spare - could one working 128M be made out of that combination?

Would it be feasible to offer a simm rebuild service?
I'm sure Mitsurugi can help you on that.
 
I also have a 32M & 64M simm spare - could one working 128M be made out of that combination?
Would still need two chips.
If only one or two chips are dead on the 128M - surely there'd be enough on the other two to rebuild it or would I need 2 * 32M and 1 * 64M to guarantee a fix?

Either way a dead 128 & a working 32M & 64M are no use to me...
 
True. I thought you meant take one 32 and one 64 and make a 128. To repair one it would be ok. The thing is if I could devise a system of determining which chip is bad without desoldering them I could fix a ton of simms I have. If someone could determine which order each chip is written in on the simm we could do this easily.
 
So the problem is that there is no simm test on CPS3 that'll tell you which chip is faulty, just which simm is faulty.

What about if you used the custom bios to program a pre-set pattern onto a simm could you desolder a chip and read the contents which would then show how the data is written to the simm?
 
Well we know that the CPS3 system writes to the SIMMs and is able to determine if a write was successful or not. So if the CPS3 system indicates that a SIMM is bad, could one design their own programming socket to install the SIMM into, then try writing to each chip on the SIMM and find out which one is not working properly?
 
Well all you would need to do is write any simm with a single file using the SuperBIOS and then desolder the chip and read it in your programmer and then compare the data with the full file. Then note the offsets of each chip. If you write the simm using the SuperBIOS in the files menu and there is a bad chip it freezes and tells you the offset it froze at. So if you know what chip is responisble for each offset you can determine the bad chip.

Problem is my $700 Topmax 2 programmer does not support either of the chips on the SIMMs. The earlier revision of the Topmax did though. I might buy a cheaper programmer just to do this but I'd rather not have to. If someone else wants do this part for the community it would be awesome. Otherwise, I can around to it eventually.
 
Cool. Well, under the power of alcohol, I went out and blew $325, including shipping, for a working complete SF3:New Generation, CPS3 system. Heh. Was going to buy one eventually, but I honestly don't know if that was a good price. Took forever to get a CPS2 A-Board, so this was good enough for me.
 
honestly don't know if that was a good price.
Well....

It's not great but by the time you buy two more 128mb SIMMs and get the cart converted you will be around $500 which is what I sold my last CPS3 SuperBIOS kit for a few years ago. I would go ahead and spring for a SCSI2SD also. Trash that SCSI CD-Rom drive.
 
Well all you would need to do is write any simm with a single file using the SuperBIOS and then desolder the chip and read it in your programmer and then compare the data with the full file. Then note the offsets of each chip. If you write the simm using the SuperBIOS in the files menu and there is a bad chip it freezes and tells you the offset it froze at. So if you know what chip is responisble for each offset you can determine the bad chip.

Problem is my $700 Topmax 2 programmer does not support either of the chips on the SIMMs. The earlier revision of the Topmax did though. I might buy a cheaper programmer just to do this but I'd rather not have to. If someone else wants do this part for the community it would be awesome. Otherwise, I can around to it eventually.
Maybe it's time for CPS3 SuperBIOS v2...

I'd like to add auto update of the code and speed up that damn long flashing process.....
 
Well all you would need to do is write any simm with a single file using the SuperBIOS and then desolder the chip and read it in your programmer and then compare the data with the full file. Then note the offsets of each chip. If you write the simm using the SuperBIOS in the files menu and there is a bad chip it freezes and tells you the offset it froze at. So if you know what chip is responisble for each offset you can determine the bad chip.

Problem is my $700 Topmax 2 programmer does not support either of the chips on the SIMMs. The earlier revision of the Topmax did though. I might buy a cheaper programmer just to do this but I'd rather not have to. If someone else wants do this part for the community it would be awesome. Otherwise, I can around to it eventually.
Maybe it's time for CPS3 SuperBIOS v2...
I'd like to add auto update of the code and speed up that damn long flashing process.....
And you might also would like to consider to modify the device ID checks to support more "up to date" flash IC brands.

For example AMD has normal and reverse pinout flash ICs which are more easily sourceable such as AM29F016D

Am29F016D-90E (Normal pinout TSOP-48)
Am29F016D-90F (Reverse pinout TSOP-48)

OR

Am29F016D-90E4 (Normal pinout TSOP-40)
Am29F016D-90F4 (Reverse pinout TSOP-40)

The above flashes are 16Mbit and pin compatibale with the current SIMMs. BUT I couldng get them recognized by the CPS3. May be its because I mixmatched them with the current Fujistu ICs. But I think the current flashing algorithm (or commands) in the BIOS is not compatible with these AMD chips.

Ofcourse this is just an example of what I have in hand. I'm sure more cheaper and more easily accessible flash IC also exists...
 
I will be interested in 1 x 128mb ram if there are still any available. You can also contact me over on Jammaplus, shumps, arcade otaku etc by the same name.
 
If this becomes popular enough, it would be cool to be able to send in a CPS3 cart, then get back the SuperBIOS version, and be able to pick how many 128 MB and 64 MB SIMMs if DarkSoft would be able to produce those as well. I've got a New Generation setup, so it only has one 64 MB SIMM. I know i can go online and get another 64 MB SIMM from somewhere, but I'd be more comfortable buying newly manufactured SIMMs than used ones which were produced nearly 20 years ago.

Another nice feature would be the ability to put on a MicroSD card only the games/regions you want, and if the system only detects one region of a game, it automatically loads to that region. If it sense multiple regions of the same game, then the region select screen would come up. I only have the desire to play the US Region, so the region select isn't really a "feature" for me. More of a nuissance. Heh. Still, I think this system is incredible. Knowing that i can safely run real CPS3 hardware without any fear of the system going belly up on me is amazing. :D
 
I believe Darksoft is only producing 128mb simms, for the the 64mb ones you should look elsewhere, 128mb simms are the more looked after since most people have 3rd Strike, JoJoV/JoJoBA or 2nd Impact setups which came originally with the x2 64mb modules needed, New Generation and Warzard with 32mb simms are a bit more uncommon.
 
if these become available again I would be interested in at least 2.
 
I know the Neo Geo Cart and the DECO are getting all the attention right now, but I would like to politely ask if there is any update for this? I've been following the posts carefully and it seems that people think the production run happened and already sold out. I was under impression you were close to starting production and don't have the final batches yet.

I just need 1 SIMM to run my Superbios/CPS3 system.

It will also help to have an ETA so I can plan for it around my other arcade-project purchases (ST-V remote, Naomi Dimm Mod/CF, etc). Also, I need to start hiding away pennies for the NEO cart!
 
Update!

so Mitsu got a couple more of SIMMS after quality tested. They are in USA and they can be shipped to USA + CANADA people only.

We have actually got some losses in those SIMMS, so for the ones we'll be selling from now on, price will be $45 shipping included.

If you are intersted please PM me. Stock left is about 12 units.

We are doing a new batch soon. I'll keep you posted.
 
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