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Mathesar / 14mhz-accelerator

14MHz 68000 accelerator with 1MB fast ram for amiga 500
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Compatible with trap door 512k RAM expansion on A500? #10

Closed alexispurslane closed 1 year ago

alexispurslane commented 1 year ago

I'm brand new to this stuff, and reading through the forum thread where this project was introduced, it seemed like this board puts the onboard RAM in the same address location as slow RAM, which would override the slow RAM trap door expansion, while also not really being slow RAM, meaning it isn't accessible to the chips, thus limiting my machine to 1.5MB instead of 2MB, and (more importantly) making it impossible to do the Fat Agnes ECS mod to my A500 if I'm using it. Is this right or am I completely off-base? I think I'm probably wrong given your sysinfo screenshot.

Also, I recently bought a print of this board (and some ICs) off eBay, and it comes with a 68020, has anyone had any luck with using an 020 with this board before?

alexispurslane commented 1 year ago

Closed bc answer is obvious: 020 won't work (I misread what I'd bought anyway), and yes, the 1MB of "slow" fast RAM on the board will shadow the 512k of slow RAM in a trap door expansion, so best to turn that into chip RAM with the Obese Agnus ECS mod.