[Coco] Coco3 CMP color swatches

[Robert Gault]

If one assumes that the net outputs to composite and RGB monitors were 
correctly designed, then the composite and RGB colors are essentially 
but not exactly the same; just have different palette ID numbers.

Regards ml programming, the format of the composite and RGB colors will 
be different.
RGB - x x R1 G1 B1 R0 G0 B0
CMP - x x I1 I2 P3 P2 P1 P0   where I is intensity and P phase angle
However, as there is a one to one mapping of the CMP and RGB colors, it 
is easier to think of the same 64 colors being assigned different 
palette ID numbers.

You get into trouble with the CMP colors for 48 and 63 which are
xx110000 and xx111111. These colors both look like pure white on a 
composite monitor but only 48 should be. By rights 63 should be a very 
pale green. Since these two colors are wrong, probably other CMP colors 
are somewhat off and a CMP to RGB mapping is not accurate. It all 
depends on what angle xxii1111 corresponds to but it should not be xxii0000.

Stephen H. Fischer wrote:

> Hi,
> 
> Thanks for all CoCo er's tips and discussion.
> 
> I am now working on the project and found the following in Jeffs and 
> Johns Emulator.
> 
> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
> ;64 byte palette lookup table
> ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
> 
> PALETTE_XLAT DB 00H,08H,10H,18H,20H,28H,30H,38H
>        DB 01H,09H,11H,19H,21H,29H,31H,39H
>        DB 02H,0AH,12H,1AH,22H,2AH,32H,3AH
>        DB 03H,0BH,13H,1BH,23H,2BH,33H,3BH
>        DB 04H,0CH,14H,1CH,24H,2CH,34H,3CH
>        DB 05H,0DH,15H,1DH,25H,2DH,35H,3DH
>        DB 06H,0EH,16H,1EH,26H,2EH,36H,3EH
>        DB 07H,0FH,17H,1FH,27H,2FH,37H,3FH
> 
><snip> >