Re: Output devices for MuP21
On Mon, 21 Nov 1994, Jeff Fox wrote:
> Here is Chuck's response:
> You can't meet the PAL spec with the MuP21 video output. That will
> require a instruction to skip 1/4 a color period, whereas NTSC needs
> to skip only 1/2. However, you might be able to generate a displayable
> signal. For example, NTSC might work without interlace, depending
> on the monitor?
> The common PAL chrominance sub-carrier is 4.43 MHz. The crystal
> oscillator would have to be 4 times that.
Provoded, that the oscillator is changed to something close to 17.7, can
one generate a monochrome signal, displayable on PAL?
Another possiblity is to generate the green signal from an RGB triplet
and duplicate it to the R & B, so that an old RGB monitor could be used.
Is that possible?
--
Penio Penev <Penev@venezia.Rockefeller.edu> 1-212-327-7423