Sinclair ZX80 / ZX81 / Z88 Forums

test_wrxi_3.p New version. I tried to mockup a theorical high resolution face symbol. I also removed the blurred picture, it now shows the flickering/ghosting picture (almost the worst case scenario of a single frame in use). It is good to know that on some LCD display the picture is reasonably sta...

Flickering is expected, the overall rate drops to 50% The top-right face IS blurred, it is just a fancy useless experiment. The top-left face is drawn on a single frame only, the bottom-right is drawn on both the frames and sould appear in standard 256x192 resolution as the top row. The only real el...

Your screenshot seems not to match Stefano's. That is the differene of AI (artificial incompetence) versus reality :mrgreen: Well, yes. You are both right, I haven't considered the phase. I have no way to predict whether the TV display will be drawing the even or the odd lines series when the drive...

I don't remember whether I placed the display buffer at 32768. It's a 12k blob, it overflows easily.

I took a photo with my phone while the picture was being generated on EO.
Then I cut a portion of it, but the result is what I was hoping to get.

M1NOT shouldn't be necessary. In theory a 32K RAM expansion capable of wrx graphics should work.

Wonderful!

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

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.

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.

I've noticed that ARX graphics driver is still unstable when used in 64 rows mode if the break detection is excluded. I'm investigating. In attachment a bouncing balls demo in 64rows mode (runs much faster than on a full graphics page). The ARX version incorporates the BREAK detection as a workaroun...