[Coco] PICs and S-Video

Gene Heskett gene.heskett at verizon.net
Thu Feb 23 10:59:54 EST 2006

On Thursday 23 February 2006 09:07, Chris Hawks wrote:
>---Reply to mail from John Kowalski about [Coco] PICs and S-Video
>> Maybe I'm overlooking something, but it seems that maybe an ordinary
>> 556 (dual timer) chip could do the trick.  It wouldn't delay the
>> HSYNC per-se, but I figure it could be used to generate a new HSYNC
>> signal using the original HSYNC for reference.
>> Possibly something along the lines of:
>> -Timer 1 being set to the delay between the original HSYNC and the
>> new HSYNC. -Timer 2 being set to the pulse width of the new HSYNC.
>> -The original HSYNC would trigger timer 1 and reset timer 2.
>> -The output of timer 1 would be your new HSYNC and also trigger
>> timer 2. -The output of timer 2 would reset timer 1.
>    Yeah, that's how it started. But, the 555(6) output is high when
> the trigger is low (and HSYNC from the Coco3 is a high pulse), so
> I'll have to invert HSYNC (another chip!) before it's fed to the
> timer 1. I should be able to de-couple the connection from timer 1 to
> timer 2 with an RC network.

How about just setting the timer to trigger on the trailing edge, and 
set the time to around 60 u-secs?  The timed out condition becomes the 
new synch pulse then.

>---End reply
>Christopher R. Hawks
>--- Hey! It compiles! Ship It!

Cheers, Gene
People having trouble with vz bouncing email to me should add the word
'online' between the 'verizon', and the dot which bypasses vz's
stupid bounce rules.  I do use spamassassin too. :-)
Yahoo.com and AOL/TW attorneys please note, additions to the above
message by Gene Heskett are:
Copyright 2006 by Maurice Eugene Heskett, all rights reserved.

More information about the Coco mailing list