Re: [stella] The heart of darkness. (was midified VCS)

Subject: Re: [stella] The heart of darkness. (was midified VCS)
From: "Frank Palazzolo" <palazzol@xxxxxxxx>
Date: Sun, 18 Nov 2001 21:11:03 -0500
That's an interesting schematic.  Since the FET's are n-channel (NMOS), 
they must act like a switch that's on when the gate goes high.  When it goes 
low, the output voltage probably stays preserved at the current state for a 
little while, because of gate capacitance.  Since all the gates are driven by 
H01 and H02, I can assume these are oscillating signals (Horizontal clocks 
of some kind), so they never stay low for too long.

So, I guess you think of the FET's as D-type flip-flops as long as they get 
clocked often enough.  (You probably wouldn't want to duplicate the logic 
this way, but you could.)

FWIW, I think the astrocade custom chips use this same kind of technique.  
You can see the bare FET's in their patents.

I haven't been following this thread very carefully - have these schematics 
been posted anywhere yet?  Are they going to be?  Pretty please? :)


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