Book "Son of cheap video"

[Moggy]

video on a zeddy?
Any ideas how this could be implemented on the Zeddy?

http://laughtonelectronics.com/arcana/B ... aster.html

[Paul]

(trying to be also funny without wanting to irritate/annoy you Moggy)
As it would require to stop the ULA from what it's normally doing , this would be something for the new ULA's that are under heavy development.
But instead of this, why not integrate the Colormodule of the Lambda8300 instead? You could add the SPONZY ROM ....

This book describes very good in detail how the guys at Sinclair had to design the Zeddy, and why it is the way it is...

[Moggy]

(trying to be also funny without wanting to irritate/annoy you Moggy)
As it would require to stop the ULA from what it's normally doing , this would be something for the new ULA's that are under heavy development.
But instead of this, why not integrate the Colormodule of the Lambda8300 instead? You could add the SPONZY ROM ....

This book describes very good in detail how the guys at Sinclair had to design the Zeddy, and why it is the way it is...

Some good ideas there Paul and You never irritate or annoy Me
As I have said before the work of You and the German ZX Group I find superb.
Annoyed? verärgert, nie (Excuse My bad German)

Fond Regards
Moggy ( Or as Jens calls Me MOOGY)

[sirmorris]

I'm loving that site!

[Dr Jefyll]

I'm loving that site!

I humbly thank you for that, sirmorris. And likewise thanks, Moggy, for posting the link to my site. I apologize for not dropping in sooner but your posts have only recently come to my attention. (Frankly, I'm a more or less a newbie webmaster, and I decided to google my own domain name, just out of curiosity to see what would turn up!)

video on a zeddy?
Any ideas how this could be implemented on the Zeddy?

Is it the Sinclair ZX81 that you want to use Cheap Video for? I think it may already be included in the ZX-81 design! I built a ZX-81 years ago (I still have it!), and now I'm re-examining the schematic. The Don Lancaster video trick isolates the memory data bus from the CPU so you can feed fake NOPs (or similar) to the CPU and cause it to accesses memory locations sequentially during each horizontal scan line. The real memory data is what gets shifted out as video. The ZX-81 schematic may show a variation on this, which I would need my oscilloscope to confirm. I'd be happy to look into that -- just let me know. Or, more likely, perhaps you folks understand the ZX-81 video circuit very well already, so no worries.

Thanks again to you all, and it's nice to see folks still interested in the ol' Sinclair! Cheers,

Jeff
My site overall: http://laughtonelectronics.com
Cheap Video (part of the KK computer article): http://laughtonelectronics.com/arcana/B ... aster.html