[sdiy] My New Project - PCSYNTH

[Roy J. Tellason]

On Tuesday 07 June 2005 12:48 pm, Jaroslaw Ziembicki wrote:
> ----- 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.

Sounds a lot like what Don Lancaster did in his "Cheap Video Cookbook" and 
"Son of Cheap Video" where the hardware requirements just got less and less 
as he went along...

Got bunches of those kinda parts around here,  and there's no reason I can see 
why you couldn't throw more than one processor at some problem,  if that'd 
work better.  It ain't like they're expensive or something any more.