[Coco] Will this build-your-own s-video board work for CoCo 3?

Steve Bjork 6809er at srbsoftware.com
Wed Mar 9 00:06:12 EST 2011

A simple Google search came up with this from CoCo3.com...

In the case of the Amiga 1084, it requires combined negative sync in
analog RGB mode, so you need to take the separate positive H and V sync
from the CoCo and feed them into the inputs of a a NOR gate a 74LS02
has four such on it, and use the output of that NOR gate to provide
sync to the Commodore monitor.

The Neobitz board is design to work with the Amiga and its combined 
negative sync.

Please note that only standard Video will give color in Pmode 4 (the 
black, white, Red & Blue mode).  This causes artifacting of NTSC signal 
do to too high resolution to convey proper color information.  In other 
words, Pmode 4 only gives color because of an error.

The s-video, component and RGB output will be black and white and no 
color in Pmode 4.  (Just like in PAL version of the CoCo.)

Steve (Mega-Bug) Bjork

On 3/8/2011 7:47 PM, Blake Patterson wrote:
> But, doesn't the CoCo 3 wire straight into a 1084? From what I've read
> it just works on that screen. Wouldn't that mean it's the same signal
> type of the Amiga?
> Thanks.
> (I can't go straight to a 1084 with a properly wired simple cable, then?)

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