Talk:VGA Hardware

Things that still need to be done:

• I need to reverse engineer more documentation for the sequencer.
• I need to test some additional GC bits for effects.
• Read Modes 0 and 1, Write modes 1,2,3 (this is easy as this documentation is rather complete. I Have not tested all details of this stuff)
• DAC Mask Register (the latest spec doesnt document it)
• Color Logic (There's more to this than the eye meets. I can write this from info out of Abrash's book, but i should still test it anyway. (It partially depends on the Sequencer)
• Sequencer: byte word doubleword mode, doublescanning, why 256-color modes have halved horizontal resolutions. Some of this depends on the sequencer operation...

- Combuster 17:15, 3 January 2007 (CST)

What you can do:

• Proof-read it, check for sanity.
• Comment on n00b-friendliness
• check registers and timings
• probably a lot more :)

- Combuster 16:55, 27 December 2006 (CST)

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Detection

You mention checking for VGA compatability before use, but you make no mention of how to check for VGA compatability. I have never programmed for VGA so could not write this myself. --Tyler 18:28, 1 February 2007 (CST)

Well, I don't have any detection code either, because I know of no standard way existing of doing probes. You can deduce an probing method from the info listed, however, but it is not guaranteed to leave non-vga machines intact (see forum thread on ATI Mobile cards). You may want to google for it and contribute whatever you find - Combuster 03:38, 2 February 2007 (CST)

Well i have had a good search. Unfortunately it really is all so device independent that it is impossible to tell. I do recall once reading some kernel source code that verified a colour system was being used in it's initialisation routine. Unfortunately i have misplaced the code so if anyone comes across it, i think it may be used as such. I will keep searching. --Tyler 10:08, 2 February 2007 (CST)