[sdiy] My New Project - PCSYNTH

[Jaroslaw Ziembicki]

----- Original Message -----
From: "Rainer Buchty" <rainer at buchty.net>
To: "Gorka Garcia" <torpedo at demadrid.com>
Cc: <synth-diy at dropmix.xs4all.nl>
Sent: Tuesday, June 07, 2005 4:05 PM
Subject: Re: [sdiy] My New Project - PCSYNTH


> ...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 :)


That's right;  I can recall how long it took on the ZX81 to run a simple
Basic loop that displayed numbers 0,1,2,3,4,... It took approx.
ONE SECOND per number...

But the idea of using the Z80 microprocessor for video generating was
brilliant! As far as I recall, the Z80 jumped into the video memory
and "executed code", and the µP bus signals were used for video signal
generating.

Regards, Jarek