nesdev.com
http://forums.nesdev.com/

Do all games have 128k of ram?
http://forums.nesdev.com/viewtopic.php?f=12&t=16676
Page 1 of 1

Author:  olddb [ Mon Nov 06, 2017 6:21 pm ]
Post subject:  Do all games have 128k of ram?

Hello. Im new here.

Been lurking for a while. Thanks to everyone. I learned to much from this forum, not only about the snes, but about electronics in general. Still a long way to go. Thank you again.

Ok. So my question is: Do all games have 128k of ram or is the second 64k chunk in cartridge?

Author:  tepples [ Mon Nov 06, 2017 6:37 pm ]
Post subject:  Re: Do all games have 128k of ram?

The Super NES Control Deck contains 128 KiB of work RAM connected to the S-CPU, 64 KiB of video RAM connected to the S-PPUs, and 64 KiB of audio RAM connected to the S-SMP (audio CPU) and S-DSP. This RAM is available to all games.

Some Game Paks contain additional RAM, usually 2 to 32 KiB and usually battery-backed and for saving a campaign's state between sessions. Games using the Super FX coprocessor (MARIO, GSU, or GSU2) contain extra RAM for use as a frame buffer.

Author:  psycopathicteen [ Mon Nov 06, 2017 6:42 pm ]
Post subject:  Re: Do all games have 128k of ram?

There is 128kB of RAM in the system. Most emulators allow games with an additional 128kB of RAM, but you can do a lot more with a physical cartridge.

Author:  olddb [ Mon Nov 06, 2017 6:53 pm ]
Post subject:  Re: Do all games have 128k of ram?

Thank you.

In a document I saw the second 64k chunk labeled as "extended ram" so that made me curious.

This makes that clear.

So to access the cartridge sram I just need to change the header and r/w from banks $70- $7d, right?

I mean on an emulator.

Author:  psycopathicteen [ Tue Nov 07, 2017 9:15 pm ]
Post subject:  Re: Do all games have 128k of ram?

If I understand you correctly, yes.

Page 1 of 1 All times are UTC - 7 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/