Memopak 16k - in need of new caps etc. before being used?

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Lardo Boffin
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Re: Memopak 16k - in need of new caps etc. before being used?

Post by Lardo Boffin »

The dip switches control whether the RAM pack is a master or slave etc. You can plug mote than one of these at a time I believe.
I am sure I have a manual that shows what the settings are somewhere. I will have a look later.
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Lardo Boffin
Posts: 2169
Joined: Sat Nov 26, 2016 2:42 am

Re: Memopak 16k - in need of new caps etc. before being used?

Post by Lardo Boffin »

ZX80
ZX81 iss 1 (bugged ROM, kludge fix, normal, rebuilt)
TS 1000 iss 3, ZXPand AY and +, ZX8-CCB, ZX-KDLX & ChromaSCART
Tatung 81 + Wespi
TS 1500 & 2000
Spectrum 16k (iss 1 s/n 862)
Spectrum 48ks plus a DIVMMC future and SPECTRA
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1024MAK
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Location: Looking forward to summer in Somerset, UK...

Re: Memopak 16k - in need of new caps etc. before being used?

Post by 1024MAK »

Yes, basically if you have two 16K byte memory expansions and the first one is a Memotech, you can use them together so you have a total of 32K bytes of RAM.

The DIP switches alter the address decoding on the memory in the pack and some of the “through signals” to the edge-connector on the back of the Memotech, and so control the address decoding of any following memory expansion...

Mark
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Papalapa
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Re: Memopak 16k - in need of new caps etc. before being used?

Post by Papalapa »

Lardo Boffin wrote: Sun Jun 30, 2019 12:20 pm This looks like it.

http://www.zx81.de/memotech/memory16.txt
Many thanks Lardo, I see that in fact they are only used to set the RAMpack as master or slave. Humm.... I remember that the original XT IBM PCs also have the same DIP switches to setup the floppy drives as A or B

Long time ago.... :D
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1024MAK
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Re: Memopak 16k - in need of new caps etc. before being used?

Post by 1024MAK »

Yeah, just keep in mind that in this context, master and slave are a little misleading, first and second fit slightly better - first memory expansion and second memory expansion :mrgreen:

Mark
ZX81 Variations
ZX81 Chip Pin-outs
ZX81 Video Transistor Buffer Amp

:!: Standby alert :!:
There are four lights!
Step up to red alert. Sir, are you absolutely sure? It does mean changing the bulb :!:
Looking forward to summer later in the year.
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