External 3B1 Monitor Project Status; and help needed
Bruce Lilly
bruce at sonyd1.Broadcast.Sony.COM
Sat Feb 2 05:57:05 AEST 1991
In article <38657 at cup.portal.com> thad at cup.portal.com (Thad P Floryan) writes:
>
>Only real problem remaining seems to be due to the 3B1 not quite producing a
>"Hercules" compatible video signal ... my guess is the onset of the video
>information seems to be too soon after a horizontal sync, causing the first
>several pixels on each line to not be displayed.
>
>Attempts to delay the video by running through a l-o-n-g chain of inverters
>doesn't do anything discernibly different and I'm wondering if a digital delay
>line might be necessary.
An inverter will only give a few nanoseconds of delay. Try a
FIFO, clocked at the pixel clock rate. Alternatively, there may
be a way to change sync to active ``video'' timing in
software....
>If anyone has experience with "digital" video (contrasted with "analog" video)
>or can point me to some reference books that might address this kind of
>problem, I'd be greatly appreciative.
The books published about digital video are not likely to discuss
computer bit-mapped diplays.
>It also seems that "Hercules"-compatible monitors don't have any horizontal
>width adjustments meaning the 3B1's display doesn't span the entire CRT.
>
[ ... ]
>
>And it appears the Hercules monitors automatically center the image on the CRT
>face, so it would appear that some method of "stretching" the horizontal scan
>is needed (to fill the CRT left-to-right). Again, any ideas or pointers to
>reference material would be appreciated.
How about a better monitor?
--
Bruce Lilly, Product Manager, | bruce at Broadcast.Sony.COM
Digital Television Tape Recording, | uunet!sonyusa!sonyd1!bruce
Sony, 3 Paragon Drive, Montvale, | lilb at sony.compuserve.com (slow)
NJ 07645-1735 | Telephone: 1(201)358-4161 | FAX: 1(201)358-4089
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