Hacking GBA Save Game Problems with CycloDS

[castle]

I'm having some problems with the GBA emulation on my CycloDS. According to the CycloDS manual:

"CycloDS Evolution allows you to launch GBA games directly from the CycloDS Evolution game list. Some games must be patched in order for them to properly save data – this is done automatically on-the-fly. GBA games saves are stored in a directory called “GBA_SAVE” in the
root directory of your MicroSD card and are automatically backed up from your slot 2 device when necessary"

However, I have not been able to get emulated GBA roms to save correctly. To clarify, whenever I run a GBA rom from the CycloDS menu, it will appear to save while I am playing the game, but when I restart my Cyclo and load up the game again there are no saves in memory. I assume this is due to a problem backing up the slot 2 SRAM to the MicroSD, but I don't really know enough about the process to diagnose it further. The manual says that this backup happens "automatically," but clearly it is not happening at all in my case.

Some notes:
- CycloDS is at latest firmware, 1.55.
- I'm using an EzFlash V slot 2 cart
- This occurs in both PSRAM and NOR modes

Is there something basic I'm missing here? Is there some way to force backup of the GBA ram? I can't seem to access the Team Cyclops forums, so I'm hoping some of you will be able to help.

 

[Chrono_Tata]

First thing first, just to dispel any confusion, what you are doing is not "emulating" the GBA. The DS does have GBA hardware and it runs GBA games natively with no emulation needed.

Anyway, your problem could be that your EZFlash cart is faulty or has depleted internal battery. I suggest getting the GBAExploader tool and try running and saving GBA roms with that. If it still doesn't save then you know there is a problem with your EZFlash, in which case search Google for a guide on how you can replace the battery, or if you bought it recently get it replaced.

 

[castle]

Hi chrono, thanks for the reply. Heh, I'm aware it's not actually emulating, not sure why I said that...

Anyway, I was under the impression that the EzFlash was storing the save data in its sram, and the Cyclo would automatically backup this sram whenever it was modified. There would be no need for battery power during this process, as the save file should be written as hard data to the microSD while the NDS power is on. The battery should only effect data that remains on the EzFlash after it has been turned off, not hard data that has been backed up to the MicroSD. Is this reasoning correct?

The EzFlash is fairly new, so I wouldn't expect the battery to be bad, but you never know...

In any case your suggestion to try GBA Exploader is a good one. Unfortunately I'm traveling at the moment and don't have a way to transfer it to my MicroSD card today, but I'll get back to the thread when I get a chance to try it out.

 

[castle]

After some more testing I believe it is a battery issue. I installed and tried to use GBA Exploader and had the same issue, so it's not something specific to the CycloDS firmware.

I now have a better understanding of how saving works. I guess when the Cyclo (or Exploader) loads a GBA game into the system, it's not able to run in the background, so it can't read or write from the SRAM. Thus you can't backup the SRAM as you play (or soft reset, or do anything else but play the cart as if it was a GBA game).

This means that rather than backing up the SRAM as you play, the SRAM is backed up the next time you turn on your Cyclo (or open Exploader) and the program is able to read/write from the SRAM again. Thus if you have a dead battery, it can't store what is written to the SRAM during the power off transition between running a GBA game and starting up the Cyclo.

Anyway, thanks for your help. Guess I'll replace the battery or buy a new EzFlash.

 

[Chrono_Tata]

Yeah, that's pretty much right. When the DS switches to GBA mode all NDS-specific hardware are locked out, hence why a power cycle is needed to store the save file to the MicroSD.