Sinclair ZX80 / ZX81 / Z88 Forums

Not sure if this has been posted before but even so a repeat won't hurt especially for newer members and those who may have missed it first time around.

Section 3 of the catalogue covers the ULA with a drawing of the ULA matrix cell and though not specifically mentioned as the type used on Sinclair devices the matrix cell is almost identical to the ones I have seen on a de-capped ZX81 ULA.



http://bitsavers.org./components/ferran ... _Guide.pdf

Thanks, I'd not seen this before.

Hi,

Thanks Moggy !

But i can't target the ULA used in the Zxprinter (the Ferranti ULA 1026E).

I need to place an input pin on the Zxprinter schematic.
It's the D0 input pin on the wiring diagram.
If someone can check it on the Zxprinter board... it probably the pin #10 or #16, the last unused one
(Picture of the back copper PCB)

>link to this topic<

Here are a few photos I took back in the early 2000s so unfortunately the resolution is not great, but it looks like D0 goes to pin 10 and pin 16 is unused.

Many thanks Paul !

I will able to target the famous "black wire" location !



[edit]
Ok! it's the pin #10. (Pin #16 NC)
Thanks again for pictures.