Genesis/MD SRAM files size

[Former user]

Original issue 389 created by 47iscool on 2014-07-28T04:29:10.000Z:

Not sure why, and I noticed it a while back and have been wanting to say something about it but it kept slipping my mind.

The SRAM file sizes are all 64KB in size, may I ask why?

Sonic 3K's file size on Fusion is only 2 KB's. Is it that this emulator can't detect the actual SRAM size? I haven't had any save problems or anything. I was just curious as to why they are all 64KB's.

[Former user]

Comment # 1 originally posted by ekeeke31 on 2014-07-28T07:09:34.000Z:

Nothing special, it's just the max supported size for cartridge saves and it is used by default for each game because there is no 100% sure way of knowing the original chip side beside having an internal database for all existing cartridges.

Some emulators (like Fusion) only write back the amount of data that was actually modified by the game (by starting from the end of 64K internal save until it reaches non-zero data) but that's not accurate either as most games do not use the full chip size.

All emulators also save SRAM as 16-bit while most cartridge back then used 8-bit chip so half of the data saved is useless and srm files size twice than necessary, yet nobody ever complained about those few kB.

That's why I consider this to be a non-issue, as there is no harm with saving a few kB more than necessary.

[Former user]

Comment # 3 originally posted by 47iscool on 2014-07-28T16:23:38.000Z:

I agree, not a problem. I was just wondering about it, thanks for the info.