[sdiy] My New Project - PCSYNTH

[Rainer Buchty]

>Not sure about the details of the display control done by the ZX81
>(resolution, framerate)
>
>Basically, the problem with audio is that you need to be feeding the
>DAC all the time at a fixed sample rate while you do the processing,
>whereas in video you normally can do by only updating the screen once
>you have finished processing (and waited for the time the next frame
>has to be displayed).

...which is not true for the ZX81 which is constantly feeding the pixel 
"pipeline" and is only able to do actual calculations during the 
vertical retrace. That's why it's so dog slow :)

So for simple playback the technique might be applicable, although 
rather for educational purposes or as a proof of concept.

Rainer