Sinclair ZX80 / ZX81 / Z88 Forums

There is a compatibilty Rom available that loads original ZX81 Tapes.

While every project involving our favourite computers is interesting to me, We should keep in mind that holmatic already made such a multiple machine with standard parts like z80, SRAM , rom and a custom logic chip EPM7128S from Altera. This in a spectrum case give a very nice zeddy and Jupiter comp...

The German ZX-Team has its anual meeting in begin of April. There are about 50 Sinclair enthusiasts meeting there, and as it's QLs 30th Birthday there will be a part of it dedicated to the QL. The German QL Group of the ZX-Team is about 10 Users at the moment. About seven try to attend at least on S...

There must have been at least one issue2 board
Wonder if I ever see this.

lusciousthelock wrote:two issue 1's and two issue 2's

If you own a issue 2 board, could you please post a photo?
Never seen one. I only have issue 1 and issue 3.
Kind regards
Paul

For example I made a three chip zeddy instead of four. Just because it's possible. Really ? I didn't see any pictures yet. ;) Photos would have been useless. It's a standard issue one without the ram chips. Andy's ULA fittet z80 and a auto save ram preprogrammed with zx81 rom. Andy's ULA is reprogr...

No conspiracy at all :D You are welcome to make anything you like. And please report about your progress. Most of us are planning or working something more or less usefull stuff. My projects are useless. For example I made a three chip zeddy instead of four. Just because it's possible. And I want to...

Another approach was holmatic and his hybrid computer It unites a zx80, zx81 and Jupiter Ace in a single CPLD. Less documented and not commercial. Just a single computer because it's possible. And with his ZXNU he made the opposite approach. A ZX81 in ZX81 board form factor based purely on standard ...

Grants website is a fantastic source for infos about zx80. It's not intended as a howto build a zx80 for beginners. Pokemon zx80core is a good start for beginners. PCB available, just as the parts. With a great manual. And he also offers the nmi generator as addon. There is no shortage to ULA. Sold ...

I tested one drive on a QL. It's a flp2_
I did not find a way to jumper (solder) it to become flp1_
So it has to be a twisted cable or a PC-drive compatible interface.
Kind regards
Paul