ZX80 Core - new ZX80 motherboards

Any discussions related to the creation of new hardware or software for the ZX80 or ZX81
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PokeMon
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Re: ZX80 Core - new ZX80 motherboards

Post by PokeMon »

Well their have been solutions provided by the german ZX team in the past.
Because the ULA outputs are open collector with a pull up and pushed down by a keypress and corresponding address line you can do the same over the edge connector if you listen to the IN address ($FE) and can either use the same matrix or any circuit simulation a keypress. With that you can use internal and external keyboard at the same time or use several external keyboards and maybe develop a kind of game using keyboards. :mrgreen:

There has been an official product from Memotech:
http://www.zx81stuff.org.uk/zx81/genera ... board.html

And here is an article of the german ZX team for adapting an AT keyboard to a ZX81 (german language only, beginning from page 11) ;)
http://forum.tlienhard.com/magazin/1996/magazin_396.pdf
sirmorris
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Re: ZX80 Core - new ZX80 motherboards

Post by sirmorris »

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iturbez
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Re: ZX80 Core - new ZX80 motherboards

Post by iturbez »

Thanks for the info ;) ;) ;)
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PokeMon
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Re: ZX80 Core - new ZX80 motherboards

Post by PokeMon »

So the prototype board arrived and test is in progress.
Looks good so far.

Clock working
CPU working
ROM working
RAM working

video and keyboard will be tested tomorrow.

Here two first pictures ...

component side
zx80core_top_s.jpg
zx80core_top_s.jpg (273.73 KiB) Viewed 4646 times

solder side
zx80core_bot_s.jpg
zx80core_bot_s.jpg (203.84 KiB) Viewed 4646 times

For more pictures you may look in this thread of the german board, from page 7 on (if posts ordered ascending time). ;)

http://forum.tlienhard.com/phpBB3/viewt ... &start=150
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1024MAK
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Re: ZX80 Core - new ZX80 motherboards

Post by 1024MAK »

I hope the testing continues to goes well ;)
I do like good news :D

Mark
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Looking forward to summer later in the year.
gozzo
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Re: ZX80 Core - new ZX80 motherboards

Post by gozzo »

WHOAH!!! :shock: :mrgreen:
Rink
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Re: ZX80 Core - new ZX80 motherboards

Post by Rink »

Cool!

Fingers crossed.
sirmorris
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Re: ZX80 Core - new ZX80 motherboards

Post by sirmorris »

Very good - another ZX80 for my collection :twisted:
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PokeMon
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Re: ZX80 Core - new ZX80 motherboards

Post by PokeMon »

Here one more pic how it looks like components. 8-)
zx80core_top_comp_s.jpg
(129.82 KiB) Downloaded 718 times
Today more tests passed.
Video unit is working 100%, got a nice picture.
Keyboard is working 100%, could type in very good.

Tomorrow some more final tests with LOAD/SAVE, NMIX Board (NMI generator plus video enhancement), different RAM / ROM / EEPROM configurations, using expander slot. ;)
gozzo
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Re: ZX80 Core - new ZX80 motherboards

Post by gozzo »

VERY nice! All that's needed now is some 'reproduction' cases!!!
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