[rescue] SS20/cg14 custom resolutions

[Sandwich Maker]

" From: der Mouse <mouse at Rodents-Montreal.ORG>
" 
" Thanks to a good deal of experimentation and some very helpful email
" correspondence (thank you - you know who you are), I've now got my
" SS20's cg14 running at custom resolutions - that is, resolutions other
" than the ones Sun provided for in their ROM code for the cg14.
" 
" []
" 
" The resolution-setting words for the cg14 just push ten numbers on the
" stack (in contrast to, say, the cg6, where they are strings).  For
" example, r1600x1280x66 is defined as
" 
" : r1600x1280x66
"    640 500 42 bebc200 100 a 180 2c 0 0
" ;
" 
" Here's the list of provided settings from one of my SS20s:
" 
" : r1920x1080x72  780 438 48 cdfe600  d8 2 178 56 30 3 ;
" : r1024x768x70   400 300 46 46cf710  88 6  88 20 10 2 ;
" : r1280x1024x66  500 400 42 70a71c8  40 8 118 29 18 2 ;
" : r1600x1280x66  640 500 42 bebc200 100 a 180 2c  0 0 ;
" : r1024x768x66   400 200 42 4323800  7c 5  a0 27  4 1 ;
" : r1152x900x76   480 384 4c 66ff300  40 8 104 21 1c 2 ;
" : r1152x900x66   480 384 42 5a1f4a0  40 8 110 1b 28 2 ;
" : r1280x1024x76m 500 400 4c 80befc0  40 8 120 20 20 2 ;
" : r1600x1280x76m 640 500 4c cdfe600  48 8 1b8 32  8 2 ;
" : r1024x768x60   400 300 3c 3d27848  80 6  a0 1d 10 2 ;
" 
" These numbers (given in hex, here, since that seems to be the default
" if you're poking at them with "see") appear to be, in order,
" 
" Horizontal resolution, in pixels
" Vertical resolution, in lines
" Vertical retrace frequency, in Hz
" Dot clock, in Hz
" Horizontal sync pulse width, in pixel times
" Vertical sync pulse width, in line times
" Horizontal back porch width, in pixel times
" Vertical back porch width, in line times
" Horizontal front porch width, in pixel times
" Vertical front porch width, in line times

this is similar to the details given for the tgx in the fbfaq:
====================================================
Here is the appropriate voodoo for several supported resolutions. Note also
that this will only work for the TGX or TGX+.

1024 x  768 at 60 Hz	 64125000, 48286,60,16,128,160,1024,2,6,29, 768,COLOR
1024 x  768 at 70 Hz	 74250000, 56593,70,16,136,136,1024,2,6,32, 768,COLOR
1024 x  768 at 77 Hz	 84375000, 62040,77,32,128,176,1024,2,4,31, 768,COLOR
1152 x  900 at 66 Hz	 94500000, 61845,66,40,128,208,1152,2,4,31, 900,COLOR
1152 x  900 at 76 Hz	108000000, 71808,76,32,128,192,1152,2,4,31, 900,COLOR,0OFFSET
1280 x 1024 at 67 Hz	117000000, 71691,67,16,112,224,1280,2,8,33,1024,COLOR,0OFFSET
1280 x 1024 at 76 Hz	135000000, 81128,76,32, 64,288,1280,2,8,32,1024,COLOR,0OFFSET
1600 x 1280 at 76 Hz	216000000,101890,76,24,216,280,1600,2,8,50,1280,COLOR,0OFFSET

And this is what the numbers actually mean, taking 1280x1024 at 67 as an example:

117000000	Pixel frequency or dot clock	(in Hz)
71691		Horizontal frequency		(in Hz)
67		Vertical frequency		(in Hz)
16		Horizontal Front Porch		(in pixels)
112		Horizontal Sync Width		(in pixels)
224		Horizontal Back Porch		(in pixels )
1280		Horizontal Displayed pixels	(in pixels)
2		Vertical Front Porch		(in lines)
8		Vertical Sync Width		(in lines)
33		Vertical Back Porch		(in lines)
1024		Vertical Displayed lines	(in lines)
COLOR		Color monitor flag
0OFFSET		No sync pedestal flag
====================================================
nothing is said about mod-32 increments in horizontal resolution, but
i note they're all 32-multiples...  the h-sync numbers all seem to be
mod-8 increments.

i'd like to know if anything like this works with creators - i don't
have a 3d s3, but i do have a tube that'll do 1600x1200x60.
________________________________________________________________________
Andrew Hay                                  the genius nature
internet rambler                            is to see what all have seen
adh at an.bradford.ma.us                       and think what none thought