[Coco] Adapter from Coo3 to SVGA

[RJRTTY at aol.com]

In a message dated 4/3/05 2:23:38 PM Eastern Daylight Time, 
cwgordon at charter.net writes:

<< Over the years I have been 'out of CoColand', has anyone designed and built
 an adapter that would allow the CoCo to work on a standard SVGA monitor? >>


        Yes.    That would be yours truly (me).      I have just recently
successfully completed assembling and testing a proto type
which I am taking to the Fest in two weeks.     There I am going to
demonstrate it on a real SVGA monitor.

         I used 2 video chips produced by Averlogic Technologies Inc.
They are the AL875, a fast (100Mhz), 3-channel,  8 bit per channel
ADC.  And the AL250, a scan doubler.     These chips have
an I2C programming interface which is fully implemented on the
coco3 using the cassette port exclusively.   The rest of the
converter is discrete components.   I used the coco3 to
program the video chips instead of including a dedicated
micro controller to keep cost down.   Programming is
needed only once and the chips remember thier
internal register configurations through brief periods
of loss of power (<30mins).   But they do need to be
reprogrammed if power is off a long time.   This is
not a problem since the converter has its own power
supply which can be left on with no undesirable
effects.

          I won't have units for sale at the fest but I will take
contact information from those who see the prototype in use
and want to purchase one.    I will be offering to attendees
of the fest a  special price of $45 apiece.   I purchased
10 of the PC boards from a PC board manufacture
(PBC123) and that price will apply untill they are gone.
Fest attendees will have first dibs and when they are
gone the price will likely go up in the future for
additional units.   Later on I will probably sell the
converter on the web (maybe on Roger's web site 
www.coco3.com).

       Part of the reason I did this was so Mark would not
have to bother with it himself.  He's got enough on his
plate right now as everybody here probably knows.

       So, come to Chicago if you can....... :)

Roy