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n00b
- Joined
- Aug 15, 2019
- Posts
- 5
I’ve been working on various things/ideas for a while now and a couple of months ago I finished this little bad boy.
This here is a AES/MVS <-> PC Memcard bridge, which I originally wanted to create for a MAME Arcade build I’m in the middle of, but it’s also great for general backups/restores.
So, this has a companion app that can read/write Memcard data, restore, format (not really formatting, it just replaces the entire card with freshly formatted card data, rather than me building in an SNK formatter) and decodes human-readable data such as from the header and then the game title data as you can see from the pics.
Dead straightforward.
But then took it one step further and created a custom implementation into MAME to basically use the device as a true pass-through, so this detects card presence, exactly like real hardware does, soon as it’s detected, MAMEs NEO GEO BIOS sees it, uses it and read/writes to it.
Needless to say it was frustrating to get working haha, reading and writing independently was straightforward, the MAME integration took a few weeks as I had to test, reverse engineer, keep recompiling MAME, test and more testing.
Technically only had to do one work around, because as I came to find out, all games do random card nudges to make sure it’s valid and still there, which I thought might be minimal….. errrr…. Not so much, games like Sam Sho Zero basically hammers the F out of the Memcard during gameplay. So worked around that and also it caches the save data and writes it in one go rather than doing it byte by byte, which is a good work around.
But that’s the MAME side of things.
The good part is you can play on AES/MVS take your card out, put it in this device and carry on with your PC (Or I could massively streamline this device to about a third of the size now its out of prototyping, and could potentially be used on retro gaming handhelds). Or if you want to create infinite amount of backups on your PC, remove your current data and start again fresh with the same card, to later restore old data, you can do that too. And it’s got a nice flashy light to boot.
Frustrating at times, but was mega happy once it worked!
Note: if you’re wondering about the other bits, my custom MAME also subscribes to various RAM regions (not through lua, this is direct to platform) so I can watch specific addresses, inject for cheats and I can watch scores and the credit counter (not coin counter - credit counter will give live updates when credits are added and lost - I never liked the coin counter method).
Anyhoooo, onto the next Neo Geo project!
Thanks for looking.
This here is a AES/MVS <-> PC Memcard bridge, which I originally wanted to create for a MAME Arcade build I’m in the middle of, but it’s also great for general backups/restores.
So, this has a companion app that can read/write Memcard data, restore, format (not really formatting, it just replaces the entire card with freshly formatted card data, rather than me building in an SNK formatter) and decodes human-readable data such as from the header and then the game title data as you can see from the pics.
Dead straightforward.
But then took it one step further and created a custom implementation into MAME to basically use the device as a true pass-through, so this detects card presence, exactly like real hardware does, soon as it’s detected, MAMEs NEO GEO BIOS sees it, uses it and read/writes to it.
Needless to say it was frustrating to get working haha, reading and writing independently was straightforward, the MAME integration took a few weeks as I had to test, reverse engineer, keep recompiling MAME, test and more testing.
Technically only had to do one work around, because as I came to find out, all games do random card nudges to make sure it’s valid and still there, which I thought might be minimal….. errrr…. Not so much, games like Sam Sho Zero basically hammers the F out of the Memcard during gameplay. So worked around that and also it caches the save data and writes it in one go rather than doing it byte by byte, which is a good work around.
But that’s the MAME side of things.
The good part is you can play on AES/MVS take your card out, put it in this device and carry on with your PC (Or I could massively streamline this device to about a third of the size now its out of prototyping, and could potentially be used on retro gaming handhelds). Or if you want to create infinite amount of backups on your PC, remove your current data and start again fresh with the same card, to later restore old data, you can do that too. And it’s got a nice flashy light to boot.
Frustrating at times, but was mega happy once it worked!
Note: if you’re wondering about the other bits, my custom MAME also subscribes to various RAM regions (not through lua, this is direct to platform) so I can watch specific addresses, inject for cheats and I can watch scores and the credit counter (not coin counter - credit counter will give live updates when credits are added and lost - I never liked the coin counter method).
Anyhoooo, onto the next Neo Geo project!
Thanks for looking.
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