Non-volatile gameboy saves

[stuntpenguin007]

I modded my copy of Pokemon Gold to save games without relying on the internal save battery. I'm fairly certain this mod can be performed on most other gameboy games too.

Sorry I couldn't make a video, but you wouldn't be able to see anything because of the horrible glare on the screen. Here's a picture of the cartridge.



To do this, I desoldered the SRAM chip (the one on the bottom left), and replaced it with a non-volatile FM28V020 FRAM chip. The FM28V020 doesn't require a battery to retain it's memory, and it has the same footprint as the SRAM chip that was in the cartridge so no fancy rewiring is needed. I figured this out by accident, but in order to make this mod work, you need to lift the top right pin of the FRAM and leave it disconnected.

I have a good feeling that this would work in n64 memory cards too. It just wouldn't be multi-bank (like Kibble's non-volatile n64 memory card mod)

If you decide to do this mod, please buy the chip as opposed to ordering a sample of it. It's totally up to you, but these companies can't keep making quality products if their not making any money

[lucidPerspective]

*put's hands up in the air while jumping up and down* "I was there, I was there, this is awesome!" *looks around, eyes wide with excitement*

Good work stuntpenguin! It's awesome how you figured out the voltage problem by accident, seems to always be the way with new discoveries

[e3c]

this looks awesome just pm'd both of you. any way to make it work with 4 way like the n64 one by kibble?

[lovablechevy]

that is so totally awesome!

*goes to order enough for all gb games*

[stuntpenguin007]

Just a little disclaimer: There could be unknown problems with this mod, so if anyone does this mod and something goes wrong, don't blame me.

So far I've only found one problem, and that is that the in game clock won't stay set in pokemon gold. You have to reset the clock each time you start the game.

[e3c]

what price? i want this

[lucidPerspective]

So far I've only found one problem, and that is that the in game clock won't stay set in pokemon gold. You have to reset the clock each time you start the game.

That sounds like a minor inconvenience lol. might be worth leaving the battery in there just for the clock, as long as it won't interfere with the fram chip. would that work?

what price? i want this

stuntpenguin and myself have already offered to do this for you.. no need to spam the thread, just keep it to PM's

[e3c]

Meh

[Metallica Man X]

Very interesting! ...perhaps instead of installing a new battery for the clock, instead use of those slow drain caps...then you'd have pretty much infinite recharge capability in addition to more permanent data holding power. Of course, it still comes back to weather or not the cap will interfere with the FRAM chip...

[e3c]

if it can o 4 save switch youll have over 20 right away

[stuntpenguin007]

Very interesting! ...perhaps instead of installing a new battery for the clock, instead use of those slow drain caps...then you'd have pretty much infinite recharge capability in addition to more permanent data holding power. Of course, it still comes back to weather or not the cap will interfere with the FRAM chip...

I'll have to look into that. I was thinking about capacitors earlier, but I didn't know much about them, so I thought they were all instant discharge. The big problem would be getting them to fit inside of the cartridge.

[nevermind1534]

Very interesting! ...perhaps instead of installing a new battery for the clock, instead use of those slow drain caps...then you'd have pretty much infinite recharge capability in addition to more permanent data holding power. Of course, it still comes back to weather or not the cap will interfere with the FRAM chip...

I'll have to look into that. I was thinking about capacitors earlier, but I didn't know much about them, so I thought they were all instant discharge. The big problem would be getting them to fit inside of the cartridge.

They're only instant discharge if there's enough load on them to discharge them instantly. You could use a low voltage capacitor with a decent capacitance. The big capacitor in the xbox only lasts a few days, though.

[mako321]

Very interesting! ...perhaps instead of installing a new battery for the clock, instead use of those slow drain caps...then you'd have pretty much infinite recharge capability in addition to more permanent data holding power. Of course, it still comes back to weather or not the cap will interfere with the FRAM chip...

I'll have to look into that. I was thinking about capacitors earlier, but I didn't know much about them, so I thought they were all instant discharge. The big problem would be getting them to fit inside of the cartridge.

They're only instant discharge if there's enough load on them to discharge them instantly. You could use a low voltage capacitor with a decent capacitance. The big capacitor in the xbox only lasts a few days, though.

You mean the xbox cap that keeps date and time? It lasts about 30 minutes to an hour.

[nevermind1534]

You mean the xbox cap that keeps date and time? It lasts about 30 minutes to an hour.

Maybe I have a different one?

[Haunted360]

(*EDITED*) The Xbox 360 has volatile memory for its clock. So it looses it data when you unplug it while not connected to Xbox LIVE, or the Internet at all.

I don't know why it would not be keeping the Pokemon Gold Version Clock in memory...


Maybe because it is programmed to keep updating the SRAM (The Original Flash RAM) constantly, and when you changed it to SDRAM - that is when it TRIES to access a certain 'area' of the SDRAM?

I dunno :/

Just guessing. I have no idea about this stuff yet...