VGA can be tweaked into 768x576 (30.3 kHz/49 Hz), and even 800x600 (29.3 kHz/45 Hz).
Both work for me on a regular SVGA monitor (30+ kHz? or 31+ kHz?), but I don't know about others.
Yeah, I'm hoping for someone to already have the 55hz 768x512 -- I actually "need" the 3:2 aspect ratio. (well, I don't "need" it, but it would be nice).
You'll want to look at the source code of Fractint
Thanks, that's the codebase I was partly remembering but it's been so long I couldn't remember it's name. I could have sworn there was another that set a 360x512 mode that I applied the same values to the 16 colour 720 and it worked...
But since it has the 768x576 I hope I can just decrease VT/VDE/VBS/VBE to numbers that make sense and be done with it.
So by all means play with it and even support it in your software but please give users an option to use standard resolutions if their monitors can't cope with the tweaked ones.
I will also be implementing the option of the 720x480 mode which I know is safe on everything, even non multisync displays; though it's going to be using a TSR driver for most video control so adding/removing modes is not a big deal.
It's just 768x512 is the "ideal" resolution for what this is supposed to be... strange as that might sound.
Also having fun turning the 16 colour mode into a 4 colour mode with paging. Dunno if you folks ever saw that trick -- you change the palette to page-flip. When page 0 is set you make all colours for the bottom 4 bits show ignoring the top four, then for page 1 you show the top 4 bits ignoring the bottom 4.
For example if you wanted 4 scale grey:
Code:
Page 0
0x00 = 0b00
0x01 = 0b01
0x02 = 0b02
0x03 = 0b03
0x04 = 0b00
0x05 = 0b01
0x06 = 0b02
0x07 = 0b03
0x08 = 0b00
0x09 = 0b01
0x0A = 0b02
0x0B = 0b03
0x0C = 0b00
0x0D = 0b01
0x0E = 0b02
0x0F = 0b03
page 1
0x00 = 0b00
0x01 = 0b00
0x02 = 0b00
0x03 = 0b00
0x04 = 0b01
0x05 = 0b01
0x06 = 0b01
0x07 = 0b01
0x08 = 0b10
0x09 = 0b10
0x0A = 0b10
0x0B = 0b10
0x0C = 0b11
0x0D = 0b11
0x0E = 0b11
0x0F = 0b11
Which is shockingly easy to control using the page mask registers. Just need to be careful as the page flip can trigger the appearance of some odd colour flashing (since you're changing the palette) -- so I wait for the blanking period.