Andy Rea's ULA81 Mk1

[rune]

Hi, been a while since I posted and as usual, I need some advice

I am trying to bring a ZX81 rev. 3 back to life. I have socketed all ICs and replaced the transistors. I'm using Andy Rea's ULA81 (I believe its the version 1 as it doesn't have the Altera chip and only has one jumper on top of the board). I'm also using the 32K memory board from http://speccy.pl/wiki/index.php?title=ZX81_32K

I have a 3.24Mhz frequency on Z80/pin 6 and a nice back-porch signal at the ULA and modulator via. This gives a steady white screen on the monitor but no cursor.

The video signal is 2V, has the back porch but no character info. I have connected the via for the signal directly to the video cinch.

Can someone point me to any fitting/configuration instructions for this ULA81?

And is the signal composite compatible directly from the ULA or do I need to use something like Pokemons CCB board?

Dave

[Lardo Boffin]

I have this manual I downloaded for one of these a while back.

[rune]

Perfect, thanks.

I'll have a cuppa and a read.

Dave