Why querying of EDID is limited only to VBE version greater then 2.0?

Krzysztof Halasa khc at pm.waw.pl
Fri May 15 05:09:15 PDT 2009

"Evgeny M. Zubok" <evgeny.zubok at tochka.ru> writes:

> I have S3 Trio64V2 with VBE 1.2 and I want to add the possibility of
> display autodetection via DDC to s3 driver. There is two ways to deal
> with DDC: (i) VESA BIOS Extension and (ii) directly from videochip's DDC
> registers. The later method currently is impossible to implement due to
> the lack of information about DDC registers in accessible
> documentation.

I don't know about VBE version but I'm sure it should be relatively easy
to trace the BIOS call and discover how it's done. There is at least one
util for that (using vm86 mode) named lrmi.
Krzysztof Halasa

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