What games use non-battery packed ram?

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What games use non-battery packed ram?
by on (#164770)
...and how much and for what reason?
Re: What games use non-battery packed ram?
by on (#164775)
(notices forum)
For the NES-related answer, see this post.
Re: What games use non-battery packed ram?
by on (#164778)
As far as I can tell there is no such game to use non-battery backed SRAM in a cartridge if there is no external coprocessor like Super FX.
Games that come to my mind are Super Street fighter alpha 2, star fox, doom, some power Ranger game that uses SA-1. There probably are more with a coprocessor that use non backed ram. They needed it because the coprocessor cannot access the internal ram, which with 128kb is more than enough actually.
Re: What games use non-battery packed ram?
by on (#164784)
Emulators do support ROMs with non-battery packed RAM, right? The reason why I'm asking is that RAM is starting to get pretty crowded in my game and I would like to add more rotating objects, but in order to do that I would need to separate every rotating object far enough so they're not onscreen at the same time, and the CPU has enough time to pre-process them.
Re: What games use non-battery packed ram?
by on (#164786)
I do not know if they specifically support non-backed ram, but does it even matter?
You could (if they do really not suppot it) just use battery backed RAM in the Header, and always assume it does not contain valid data on powerup (always initializing it in Reset routine or something similar).
http://problemkaputt.de/fullsnes.htm#snescartridgeromheader suggests using Cart type h01 as ROM+RAM, and as far as i can tell a max of 32kB external RAM is supported by the Header.
If you were to implement a real hardware cart, you could (in theory) attach 1MByte of external RAM mapped to $00-$3F and $80-$BF at $6000-$7FFF with just usual 74'139 external hardware (but that is another topic i guess).
Re: What games use non-battery packed ram?
by on (#164789)
In my experience emulators will always generate .srm files for games with on-cartridge RAM regardless of whether or not the header states that there is supposed to be a battery.

Assuming your emulator of choice supports cart type 01 (ROM+RAM) and 02 (ROM+RAM+battery) you can use whichever one actually makes more sense, but there probably won't be any functional difference.
Re: What games use non-battery packed ram?
by on (#164972)
Just delete the .srm file and it will emulate uninitialized SRAM, which is essentially the same thing as non-battery-backed (except it's probably actually initialized to all 0's, so you might want to test your code against an existing .srm to be sure that you're properly initializing everything, and not making incorrect assumptions).