Iv been thinking about replacing the batteries in my old game carts, up until now iv been very lucky that I haven’t lost any game saves which is goods as some are 20yrs+ old.

Anyway what I wanted to know is if remove the battery does the game save delete from the memory straight away or do I have a few minutes?

I haven’t done it, but from what I know of SRAM, it’s probably as close to instant as doesn’t matter.

If you’re that worried about it, you could try to power the cart during the process (being very careful not to short anything) and let the battery manager IC keep the chip powered while the battery is out. Probably too difficult and dangerous (to the cart if not yourself) to be worth trying, though…

BTW, you’d also want to make sure the chip-select and write signals to the SRAM were disabled, otherwise spurious noise would probably scramble something, anyway. But, again, I don’t recommend it.

You can always backup the saves with hardware like the Retrode.

Here is a pretty cool device that lets you create save states for SNES games. It also allows you to play super famicom games on a SNES.

Thanks for the info guys. I might look into getting something to back up my game saves or just wait until the battery dies then it gives me a good excuse to replay said game.

Thanks again.

I’ve heard that it is possible to connect a second battery to the system while you’re replacing the original battery, similar to what RunnerPack says. I like his idea more, though — run power to the board in place of the battery, do the swap, remove the power source.

But really, yeah, look into a Retrode, heh.

Last time I replaced a battery, I looked into installing a socket onto the SNES cart board, so that (in 20 years lol) when I have to do it again, it’s a much easier process. I followed this video, which has part numbers in the description. The battery socket he picked out fits into an SNES cart without having to modify the case. I bought a 10-pack some years ago.

It probably takes away from the “purity” of the cartridge, which is why I did my Donkey Kong Country that wasn’t saving but haven’t done my Earthbound or Chrono Trigger yet, but I think about it…