Fixing ROMs for EMS 64 GB Smart Card USB

[MottZilla]

Some new fixes to be available soon. They are so far:

Bubble Bobble Part 2
Kaeruno Tameni (Save Bank Fix, for using with new MultiSRAM Menu)
Super Mario Land 2 - 6 Golden Coins (UE) (V1.2)
Legend of Zelda, The - Link's Awakening (U) (V1.0,1.1,1.2)
Mega Man Xtreme (U) (Save Bank Fix)
Mega Man Xtreme 2 (U) (Fix + Save Bank Fix)
Star Wars (U)
Star Wars - The Empire Strikes Back (U)
Star Wars - Super Return of the Jedi (U)
Bonk's Adventure (U)
Bonk's Revenge (U)

The LoZ Fix I didn't realize had been done previously, but mine I think is different. I'll be looking around at other games to fix so now's the time if you've noticed a game that doesn't work, mention it!

[qwertymodo]

I'm currently in the process of creating my own MBC5 clone in a PLD, and this thread has me wondering, is it conceivably possible to properly handle these issues in the PLD synthesis? From what I understand, the MBC5 was *supposed* to be backwards compatible with the MBC1/2/3(minus RTC), but there are obviously differences or these issues would not occur. So, if I were to want to handle these differences in the PLD, what cases should I be aware of where an MBC5 would not properly handle code designed for an earlier MBC? There are these from earlier in the thread:

1. Game writes to 3000-3FFF to perform a bankswitch
2. Game writes a 00 value to perform a bankswitch, seeking to select bank 1 on an MBC1/2/3, but selects bank 0 on an MBC5.
3. Game writes a value greater than 1F (MBC1), F (MBC2), 7F (MBC3) to switch a bank on MBC5, the upper bits selecting some random bank.

If these are the only discrepancies, then I have some idea of how to handle them, but does anybody know of any others that I should be aware of? I would like to be able to handle this problem in my MBC clone, rather than relying on patches, if at all possible.

[reprep]

Mortal Kombat i and ii doesn't work. (the 2-in-1 package)

[lidnariq]

I feel guilty for just giving you a link rather than a Real Answer, but I've found http://gbdev.gg8.se/wiki/articles/Memor ... ontrollers really useful.

[MottZilla]

I'm currently in the process of creating my own MBC5 clone in a PLD, and this thread has me wondering, is it conceivably possible to properly handle these issues in the PLD synthesis? From what I understand, the MBC5 was *supposed* to be backwards compatible with the MBC1/2/3(minus RTC), but there are obviously differences or these issues would not occur. So, if I were to want to handle these differences in the PLD, what cases should I be aware of where an MBC5 would not properly handle code designed for an earlier MBC? There are these from earlier in the thread:

1. Game writes to 3000-3FFF to perform a bankswitch
2. Game writes a 00 value to perform a bankswitch, seeking to select bank 1 on an MBC1/2/3, but selects bank 0 on an MBC5.
3. Game writes a value greater than 1F (MBC1), F (MBC2), 7F (MBC3) to switch a bank on MBC5, the upper bits selecting some random bank.

If these are the only discrepancies, then I have some idea of how to handle them, but does anybody know of any others that I should be aware of? I would like to be able to handle this problem in my MBC clone, rather than relying on patches, if at all possible.

You have a handle on them. 1 and 2 are the issues usually seen. I've not really heard of or seen an example of 3. If you plan for multi-game storage functionality you'll just need a Master Bank Register like the SmartCard. If you don't then ROM mirroring can help with the game trying to select a bank beyond what exists. Just like properly padding up an eprom.

The SRAM Menu Patch isn't out yet but I updated my webpage with some of the mentioned fixes.

Mortal Kombat i and ii doesn't work. (the 2-in-1 package)

That cartridge is a special multi-cart that won't ever work on flash carts. While it says it is MBC1 it actually contains either additional banking hardware or it is wired in some way that is non standard to achieve multi-cart functionality. You'll just have to use the single game releases.

[qwertymodo]

You have a handle on them. 1 and 2 are the issues usually seen. I've not really heard of or seen an example of 3. If you plan for multi-game storage functionality you'll just need a Master Bank Register like the SmartCard. If you don't then ROM mirroring can help with the game trying to select a bank beyond what exists. Just like properly padding up an eprom.

Are all of these present on MBC 1, 2, and 3 games (when run on an MBC5), or are there differences between the 3? In other words, can I lump MBC1/2/3 together and treat them identically, so I only have to check "is this MBC5 or is it MBC < 5" (seeing as I have no intention of supporting the MMM01 or HuC_ mappers ). I most likely won't bother with multi-game, but that really depends how I feel down the road when I have something actually working.

So, just to be sure I'm on the right track, would handling these 3 conditions in the MBC synthesis fix all or nearly all of the games being patched here, or are there other issues going on that you are fixing with these patches?

Also, a tangential question: The MBC5 seems to support 64Mbit ROM and 1Mbit RAM, judging from the address line count on all of the pinouts I've seen floating around the internet. Are there any games that actually use these sizes, or would it be a waste to go with those sizes if I wasn't planning to add multi-cart support?

[reprep]

Densha de Go! 2 uses 64 Mbit Rom. that is the only game which uses such a size afaik. i have no idea about games using 1 mbit SRAM. LDSJ is able to use such ram though if i am not wrong.

[qwertymodo]

Densha de Go! 2 uses 64 Mbit Rom. that is the only game which uses such a size afaik. i have no idea about games using 1 mbit SRAM. LDSJ is able to use such ram though if i am not wrong.

Cool, LSDJ alone would be enough reason to support the larger RAM. As far as larger ROM, the 32Mbit and 64MBit ROMs I'm planning to use share the same footprint (with the high address line of the 64Mbit being NC on the 32), so I suppose no reason not to at least support the possibility, even if I end up mostly using 32. Thanks.

I feel guilty for just giving you a link rather than a Real Answer, but I've found http://gbdev.gg8.se/wiki/articles/Memor ... ontrollers really useful.

Don't feel guilty, that's a lot of good info and I hadn't seen that page before. And I'm sure that everyone here is glad that you just posted that link rather than trying to write all of that info here in this thread

[MottZilla]

That's right, only one game ever used 64mbit, so that 9th bit is usually totally useless.

MBC1,2,3 do have differences but I think they are reasonably compatible. Usually the incompatibility is between others and MBC5. You could look at the mapper capability to try to spot any incompatibility issues. I think though that any MBC1, 2, or 3 game would run on a MBC3 with RTC.

So you probably just need MBC3 and MBC5 modes. But there could be issues I'm not aware of.

[MottZilla]

The MultiSRAM menu patch is available as well as some new fixes and some save fixes on my website.

More patches will follow, mention any games that you have trouble with.

[TheVlad1mir]

Hi. My name is Vladimir. I am from Russia.
I and many of my friends are fans gb.
First I would like to thank the user-MottZilla and others users who support this device and release patches for games.
MottZilla your version of the program with the saved Windows Flasher Program with MottZilla's Menu very necessary. With its help it is possible to play several games simultaneously and have fun the use of GB. It was necessary. Thank you!

I found a few more games with problems.
1) Donkey Kong Land 2. The game bug at the first level of the water when trying to use the fish. Most interesting is that when you use the program (Windows Flasher Program with MottZilla's Menu) the game not bug, but lost the ability to save.

2) Mole Mania. The game throws out (just as in Battletoads in Ragnarok's World) in the battle with 3 boss levels.

[MottZilla]

I'm glad you like the MultiSRAM Menu and that it is useful to you.

I will check Donkey Kong Land 2 and Mole Mania to see if they can be fixed.

[TheVlad1mir]

MottZilla, please tell me whether it is possible to implement the ability to change the name of the Roms in your program to correctly display their menu of GB?

[MottZilla]

I'm not sure what you mean. You can change the title of a GB ROM by changing it at $134 in the ROM file before adding it to the cartridge.

If you mean something else, please give more detail about the problem.

[BornYesterday]

Wow, had no idea this thread was still going on. I just registered to say thank you, MottZilla and crew. This particular cart seems to have fairly low support from its manufacturer, and so it's awesome to see people reverse engineering and patching stuff up to work nicely with it.
I did have a question, though. I tend to use both 32M banks, with bank one dedicated to LSDJ and bank two dedicated to games and my less used audio stuff. It would be awesome to use the firmware patch to have multiple saves. I'm just wondering, in addition to how it works on a basic level, whether or not I would be able to use the patch successfully with a setup like that. I'd also like to know whether or not the firmware can be flashed back to normal, or how that works. My guess is that flashing it at all with the EMS software would set it back to its original state, is this correct at all?

Thanks again, y'all are doing some *awesome* stuff, here.

-Bornyesterday