Hacking Best Flashcart for this particular purpose?

[Proxy-Pie]

I wanna dump one custom ROM on a GBA cart, so it boots up automatically as if it was a real GBA game.
I also don't want a battery-saving issue where the card would have an internal battery that it relies on for saves.

I'm not sure if the EZ Flash IV would be the best fit for this, as I don't really want to waste one on a single ROM, but Is formatting that cart to a single ROM possible?

I think the EZ Flash 3 in 1 fat might be the best option for me, but I'm not exactly sure about that internal battery it has inside? Is that for RTC or will the cart crap out when it runs out?

 

[FAST6191]

There are no GBA flash carts that do saves and do not have an internal battery. Some people are pondering if the everdrive GBA will have this (nothing has been said but if we were designing a modern GBA flash cart it would probably head down that path).

Batteries do handle RTC if the cart has RTC in the first place. The EZ4 and the 3 in 1 do not have RTC. Their batteries are used so the SRAM chips which hold the saves until they are taken off and stored keep the data (SRAM losing data when the power goes off). I believe the modern builds of the EZ4 and definitely the 3 in 1 do not use rechargeable batteries any more, however the coin cells they use have a reasonably long life and holding data in their SRAM does not take a lot of power.

You could theoretically autoboot an EZ4 (I did something towards that end many years ago). Many people have set their 3 in 1 up to behave as an original game though -- you simply write the game to the NOR section. Finding a GBA sized 3 in 1 is a fairly hard game right now -- lots of people in the replica side of things used the GBA sized ones for their bit and I am told others in the more general electronics world used them as they were a good source of a certain type of memory. You can always mod a DS lite sized 3 in 1 to fit in a full size GBA slot but hey.

 

[Proxy-Pie]

Wait, so if the battery dies, do the saves get lost/corrupted?
I don't mind getting a 3 in 1 Lite, I wasn't planning on keeping the Fat one in it's original cart either.

 

[FAST6191]

The EZ4 can work around it, even if it is annoying to do. The 3 in 1 will keep the saves in there so yeah losing the battery will lose you the save, though you can always dump the save using a DS flash cart and a DS/DS lite.

 

[Proxy-Pie]

Well that sucks! I was hoping there'd be a flashcart that uses Flash saves by now!
How does the EZ4 work around it?

 

[FAST6191]

All games get patched to use SRAM saves instead -- it is pretty easy to patch a GBA ROM to use a different type of save (you search in ASCII for the three saves types, read the sub type beyond that and then direct two patches that are the same for every ROM a slightly different distance away from wherever you find the ASCII save type depending upon the sub type).

 

[Acidflare]

I bought a ez-flash 3in1 lite and put it in an old super mario world gba cart that stopped saving. I used some super glue and cut some of the boxing of the ez-flash 3in1 case to hold it in place. it works wonders besides the fact I broke the cable to the rumble motor by accident not a big deal though

 

[DanTheManMS]

Most old-style NOR-based flash carts can run in single-game mode if only one ROM is flashed to the cart. My Flash2Advance Ultra, for instance, will autoboot if there's only one ROM on there (great for Pogoshell), but if you want multiple ROMs you have to flash the "game choosing software" rom first before adding any games. The F2AU also has a real-time clock (mine has died by now though) and hardware real-time-save buttons, something I've never seen in any other flash cart. The problem is that you're going to have to search for a long time to find a Flash2Advance Ultra cart plus the USB cable required, and mine is not for sale.

I dislike linking to this site, but lots of the GBA flash carts they talk about on http://www.gameboy-advance.net/ would support this sort of autobooting behavior you're looking for. Again it's going to be difficult to find any of them nowadays, but those are the names you want to be looking for. I would expect that SD-based carts like the M3 and Supercard would not support this function -- Supercard doesn't at least, but it looks like FAST6191 says it is possible on the EZ-IV somehow.

Might just be easiest to get an EZ-Flash 3-in-1 and mod it to fit into a regular GBA / DS Phat, and write your game to the NOR as suggested above.

 

[Proxy-Pie]

Might just be easiest to get an EZ-Flash 3-in-1 and mod it to fit into a regular GBA / DS Phat, and write your game to the NOR as suggested above.

Well, I'm not exactly looking for the "easiest" route, I want to have a cart that won't lose its saving abilities overtime, no matter how easy replacing the battery is.

All games get patched to use SRAM saves instead -- it is pretty easy to patch a GBA ROM to use a different type of save (you search in ASCII for the three saves types, read the sub type beyond that and then direct two patches that are the same for every ROM a slightly different distance away from wherever you find the ASCII save type depending upon the sub type).

.-. Yeah, real easy...
So, if I get an EZ Flash IV, and I patch these things, will the ROM still be able to save after the battery runs out?
And if that's the case, how do I get the EZ Flash IV to autoboot?
(And seeing as we're already talking about the subject, does the EZ Flash IV support multiplayer?)

 

[Jayro]

With my EZ-Flash 4, I play my game, save in-game, then turn my GBA of and back on immediately, wait for the EZ-Flash 4 to write the save from SDRAM to the SD card, and then my save file is safe, regardless if the shit battery dies. I don't understand what's so hard for people to understand about these carts.

 

[FAST6191]

.-. Yeah, real easy...
So, if I get an EZ Flash IV, and I patch these things, will the ROM still be able to save after the battery runs out?
And if that's the case, how do I get the EZ Flash IV to autoboot?
(And seeing as we're already talking about the subject, does the EZ Flash IV support multiplayer?)

Heh, this was probably one of the few occasions where it was easier to probably do the code than describe it in words. Suffice it to say that, unlike the PC, it is quite easy to write a generic patching program for GBA saves, one that does not require a powerful PC at all but is still beyond what the GBA can do very quickly.

Also no that will not help if the battery runs out, what Jayro said is true though -- if you power cycle quickly to write it back or you soft reset (that is a harder patching trick, though still doable on a generic basis) you can dodge the dead battery. Many people really do overthink this issue though, even if there is no sure fire way around it with the flash carts that presently exist.

Some people have had issues with some multiplayer games, most work fine, especially if you do not have extra reset, sleep or similar patches installed, and you can usually get the others to work.

Autoboot, I really really do not suggest doing it for an EZ4 and I did not do extensive testing with it. What I did was take a loader built for the EZ3 to help it autoboot DS games (called ezf3me), alter the header to match the checks the EZ4 loader uses (mainly matching internal names) and flash that as the loader. In turn it would boot that, jump right to the NOR and boot that. Not enough to fool a DS into thinking the GBA cart it wanted it was in, and likely not enough to trick a gamecube that spoke to GBA games either. I only did it because of boredom.

 

[Proxy-Pie]

With my EZ-Flash 4, I play my game, save in-game, then turn my GBA of and back on immediately, wait for the EZ-Flash 4 to write the save from SDRAM to the SD card, and then my save file is save, regardless if the shit battery dies. I don't understand what's so hard for people to understand about these carts.

I don't think you're understanding the purpose of what I'm doing here. I don't plan on using the cart for playing many games and whatnot, I want to use it to make an authentic-feeling cart for a custom GBA ROM, and GBA games don't lose their ability to save after the battery dies.

 

[Jayro]

I don't think you're understanding the purpose of what I'm doing here. I don't plan on using the cart for playing many games and whatnot, I want to use it to make an authentic-feeling cart for a custom GBA ROM, and GBA games don't lose their ability to save after the battery dies.

Then designing something like an everdrive GBA might be what you need to do to achieve this.

 

[Proxy-Pie]

Then designing something like an everdrive GBA might be what you need to do to achieve this.

Ooosh >.<
I've heard that an actual Everdrive GBA might be coming out, so all I can do now is hope that it fits in with what I want?

Also no that will not help if the battery runs out, what Jayro said is true though -- if you power cycle quickly to write it back or you soft reset (that is a harder patching trick, though still doable on a generic basis) you can dodge the dead battery. Many people really do overthink this issue though, even if there is no sure fire way around it with the flash carts that presently exist.

Pardon my noobiness, but what exactly is the purpose of patching these ROMs then?

 

[raulpica]

I still have this super-crappy Chinese clone GBA cart which could be flashed using USB at home.

I suppose it was the same kind of flashcards they used to make clones? Dunno if they're still sold anymore, but try looking on Aliexpress/Taobao and see if you can find them.

Gotta say, it never kept saves reliably

 

[Proxy-Pie]

I still have this super-crappy Chinese clone GBA cart which could be flashed using USB at home.

I suppose it was the same kind of flashcards they used to make clones? Dunno if they're still sold anymore, but try looking on Aliexpress/Taobao and see if you can find them.

Gotta say, it never kept saves reliably

Ugh, All these years and we still don't have perfect flashcarts?

 

[FAST6191]

I don't think you're understanding the purpose of what I'm doing here. I don't plan on using the cart for playing many games and whatnot, I want to use it to make an authentic-feeling cart for a custom GBA ROM, and GBA games don't lose their ability to save after the battery dies.

I believe there might be some GBA games that used actual battery backed SRAM rather than the later (but still very similar in protocol and sizes available) FeRAM. They would lose saves when the battery goes.
http://problemkaputt.de/gbatek.htm#gbacartbackupids

Ooosh >.<
I've heard that an actual Everdrive GBA might be coming out, so all I can do now is hope that it fits in with what I want?

Pardon my noobiness, but what exactly is the purpose of patching these ROMs then?

GBA games use three broad types of save, four if you count no save/passwords but that is not relevant to this.
Said saves types are known as
SRAM
EEPROM
Flash

They are named for the type of memory chip that they use. They have sub types as new chips, larger chips and like got used instead of other models (the GBA lasted a few years and chip availability changes more quickly than that at the volumes they need) which is what I mentioned earlier as the differences in patching. Owing to the way the GBA was made the act of patching is actually quite easy.

GBA flash carts rather than emulating the save types like a handful of later DS flash carts instead patched the games. They patched them so rather than using the EEPROM, Flash or sub type of SRAM they originally thought they were using they instead used the SRAM of the type the flash cart had. This method stuck around for later GBA flash carts, which the EZ4 is a descendent of and the EZ 3 in 1 is kind of a spinoff of as well.

Ugh, All these years and we still don't have perfect flashcarts?

The flash carts play basically every game (the GBA does not have much stopping flash carts like the NES or SNES), store hundreds on a cart (2 gigs is more than enough to do basically all of note in the GBA library) and are near braindead simple to operate. You just have a very specific wish that is not all that worth catering to.

 

[draxoon]

How about taking an old GBA flashcart with autoboot, desoldering SRAM chip and then replacing it with FRAM one? FRAM is similiar to SRAM, but doesn't rely on battery. I've seen this done with classic GameBoy cartridges, but I don't know if it will work in GBA ones.

 

[raulpica]

How about taking and old GBA flashcart with autoboot, desoldering SRAM chip and then replacing it with FRAM one? FRAM is similiar to SRAM, but doesn't rely on battery. I've sen this done with classic GameBoy cartridges, but I don't know if it will work in GBA ones.

I was thinking the same thing, never got around to do it though. I suppose it COULD work?

 

[Proxy-Pie]

I believe there might be some GBA games that used actual battery backed SRAM rather than the later (but still very similar in protocol and sizes available) FeRAM. They would lose saves when the battery goes.
http://problemkaputt.de/gbatek.htm#gbacartbackupids

Well isn't that suckish :/
I guess I should've been more specific though.

GBA games use three broad types of save, four if you count no save/passwords but that is not relevant to this.
Said saves types are known as
SRAM
EEPROM
Flash

They are named for the type of memory chip that they use. They have sub types as new chips, larger chips and like got used instead of other models (the GBA lasted a few years and chip availability changes more quickly than that at the volumes they need) which is what I mentioned earlier as the differences in patching. Owing to the way the GBA was made the act of patching is actually quite easy.

GBA flash carts rather than emulating the save types like a handful of later DS flash carts instead patched the games. They patched them so rather than using the EEPROM, Flash or sub type of SRAM they originally thought they were using they instead used the SRAM of the type the flash cart had. This method stuck around for later GBA flash carts, which the EZ4 is a descendent of and the EZ 3 in 1 is kind of a spinoff of as well.

Ah, So in order to play GBA games on something like the EZ Flash IV, I have to patch the ROM? Is that what the "Patch Save" thing in the EZ Flash IV's software is for?

The flash carts play basically every game (the GBA does not have much stopping flash carts like the NES or SNES), store hundreds on a cart (2 gigs is more than enough to do basically all of note in the GBA library) and are near braindead simple to operate. You just have a very specific wish that is not all that worth catering to.

Right, but the DS flashcarts don't lose their save files, do they?