Repro not holding my save files

Hi there, I'm a bit new to the repro world, and I was starting to make my first repros with the Muramasa PCB which has been working great for games that don't need save files... yesterday I was tried to create some games that save, like Live a Live or Megaman and Bass... and everything was fine.. until a realize that my games weren't saving files after ~10 minutes.. actually they do save files, if I power off the console and I immediately play again I can see my save files, but if I wait longer than 10 minutes without powering on the console.. I lost everything.. of course, I've checked the batteries and capacitors and they seem to be working fine. So I was guessing if my SRAM was maybe the wrong one (HM6264AP-12), I've just bought something that said 6264 but I didn't know there were different versions. Could you please lend me a hand with this? this is a picture of my PCBs:



Thanks and sorry for my English

You see, HM6264AP is used for games that don't hold the save game after console power off.
You will need HM6264ALP, as mentioned in the data sheet.

http://www.komponenten.es.aau.dk/filead ... HM6264.pdf

"Battery back up operation capability (L-/LL-version)"


Also make sure the batteries voltage is enough as well!

And one more thing. Instead of 74LS parts try using 74HC.

oh thanks! this information will help me a lot! then I'll try different parts!

Would you recommend this one AS6C6264-55PCN?

Yeah, that one should be OK for battery backup.

Why is the D1 diode on one board installed the other way around?
The top of the photo reminds me on... a closeup of your hips exposed and wearing only a blue slip as underwear?
Or whatever, I guess most photographers would die for making a shot like that once in their lifetime : )

hahah i didn't see the pic that way xD, and yes! I've also spotted that diode haha, it's already fixed though xD



what's the difference between 74LS and 74HC?

74HC parts are CMOS and thus consume less current when in a steady state, which means the battery will last longer if they're connected to it.