ZXpand primer

Discussions about Sinclair ZX80 and ZX81 Hardware
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mrtinb
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Re: ZXpand primer

Post by mrtinb »

There is also a new CPLD update, so you don't have to switch memory configuration with M=L / M=H. This CPLD update enables the RAM both at address 8-16k and 40-48k. The same physical RAM will be present in both places.
Martin
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ZX81, Lambda 8300, Commodore 64, Mac G4 Cube
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1024MAK
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Re: ZXpand primer

Post by 1024MAK »

David G wrote: Thu Sep 29, 2022 12:45 pm By the way, what is the "firmware" on the ZXpand? Is it the GAL/CPLD programming or is it the PIC software?
As far as I am aware, It’s the flash ROM code for the PIC microcontroller. In the PIC it’s in two parts, the “normal” code and a more primitive code that can be used to re-flash the ROM if the “normal” code is corrupted.

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