Sinclair ZX80 / ZX81 / Z88 Forums

Can anybody test this one ?
It should work in WRX mode with 32K ram.

You should see 2 lines, one will appear in standard resolution, the other one sould be more refined.
The resolution should be 256x384 interlaced.

Tried it on real zeddy with ZXpand and it just crashes to the cursor.
Some instruction on how you want it used, type of set up, real kit or emulator etc would be useful.

Eighty One with the WRX graphics option enabled and 32k ram runs properly (with the advanced video effects enabled).
Obviously I'm pushing it to the limit, I wouldn't be surprised if the program crashes on a real zx81.

384 lines
what type of sourcery are you trying to use??

I was thinking about the fact that since the ZX is "executing" the display and on a standard machine if I remember properly just 25% is left for the program execution, doubilng the "execution of the display" should not be possible since it will exceed the 100%

Anyway even if not 384 probably more than 192 is possible... please break the limits!!

The idea was to show two different high resolution frames.
The second time the CRT beam should pass slightly shifted, between the previously displayed lines.
This could produce a 192x2 picture, slightly flickering with overlapped pixels

Unless it's usable on a real zeddy I can't see the point other than a proof of concept for emulator use, if it's just a see what's possible exercise for Eighty One then yes I get it but something for real kit would be more useful I would have thought.

stefano wrote: ↑Tue Apr 30, 2024 7:53 am The idea was to show two different high resolution frames.
The second time the CRT beam should pass slightly shifted, between the previously displayed lines.
This could produce a 192x2 picture, slightly flickering with overlapped pixels

no clue on how to slightly shift the lines but the idea seems anyway interesting and doable on a real zx81
if not for higher resolution it might be used for a three gray scale image: white with both images pixels white, gray with one white and one black, and then black with both images black
and to increase resolution you might use some of the upper or lower borders

Works as expected on my ZX81NU (56K, M1NOT active):
Siggi

Your screenshot seems not to match Stefano's.

But it looks better than Stefano's