Do all games have 128k of ram?

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olddb
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Do all games have 128k of ram?

Post by olddb »

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?
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tepples
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Re: Do all games have 128k of ram?

Post by tepples »

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.
psycopathicteen
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Re: Do all games have 128k of ram?

Post by psycopathicteen »

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.
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olddb
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Re: Do all games have 128k of ram?

Post by olddb »

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.
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psycopathicteen
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Re: Do all games have 128k of ram?

Post by psycopathicteen »

If I understand you correctly, yes.
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