More than 64K system (heap) memory

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More than 64K system (heap) memory

Unread post by NovaCoder »

Let me start that I don't know much about the (real) Genesis hardware but as far as I understand it the stock hardware only supports 64k of system (working) RAM. Do any commercial games expand this memory limitation by including extra system RAM in the cartridge?

I did a quick google search and found this ... drive-pro/ which looks like it expands the amount of system memory available to a real Genesis but I could be reading it completely wrong :lol:

Does the MiSTer core support more than the standard 64k?

I'm just interested because I'm thinking about playing around with some home-brew development :D
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Chilly Willy
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Re: More than 64K system (heap) memory

Unread post by Chilly Willy »

The MED Pro lets you write to what would normally be rom in the cart space. It's not system ram. The system ram in the MD is only 64KB, but mirrors across the top 2MB of space from $E00000 to $FFFFFF. Theoretically, you could expand the MD system ram to 2MB in that space. You'd need homebrew to use it as nothing was ever written expecting more than 64KB of system ram.
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