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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