Memotech Memopak 32k

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1024MAK
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Re: Memotech Memopak 32k

Post by 1024MAK »

siggi wrote: Tue Oct 10, 2017 10:34 am
Lardo Boffin wrote: Mon Oct 09, 2017 4:28 pm Lots of nice little spaces ready for additional chips to maybe make it up to 64K?
The board itself may probably also be used for 64K ram modules. But AFAIK the Memotech rams contain a programmed chip (PROM?) for address decoding. So you would need to get the appropriate PROM for the 64K board....

Siggi
IC5 is the "fast" PROM. Most of the Memotech boards I have seen use a device made by "MM", although I have forgotten the full name of the company :oops:
Needless to say, this PROM and others like it become obsolete many years ago.
I've got a datasheets somewhere for it.

Mark
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gammaray
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Re: Memotech Memopak 32k

Post by gammaray »

From our forum a link to http://www.zx81.de/memotech/memory64.txt

explains 64K function, the 4 dipswitch setting seem to be for setting 8-16K
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