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Re: Hk Cqvst wrote: nVidia + gamma !FIXED!

Cross-posted to 3 groups.

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In comp.os.linux.misc Unknown <dog@gmail.com> wrote:
> On Tue, 20 Jan 2015 21:16:18 +0000, Jerry Peters wrote:
> > In alt.os.linux.slackware Avoid9Pdf@gmail.com wrote:
> >> My Windows-using mate insists that the vga is bidirectional; ie. that
> >> the display informs the PC <what settings it needs>. Since the modern
> >> LED:1920x1080 is forced to comply with the OLD vga spec. [and pin-out},
> >> I don't believe him.
> >> 
> > Try looking up EDID. From wikipedia:
> > The EDID includes manufacturer name and serial number, product type,
> > phosphor or filter type, timings supported by the display, display size,
> > luminance data and (for digital displays only) pixel mapping data.
> > 
> > Note the luminance data. It could poossibly be your display
> > mis-informing the video card or its driver about its requirements.
> > 
> > You assume that the video card and driver behave exactly the same with
> > the CRT and the LCD displays.
> ---
> Yes, I don't believe that any signal goes from the display to the PC's
> vga connector. Ie. it's NOT bidirectional.
> Why else would the human need to tell the system about the displays 
> parameters?

> I looked at the EDID wiki, and don't like it;
> although I can read/write schematic diagrams and design hardware.
> The explanations [wiki] must be structured: like top-down-software.

While you are certianly free to "believe" whatever you want, in this
case your beief would be wrong.  The EDID signal most definetly goes
_from_ the display _to_ the video card.  It is used so that the display
can tell the computer what resolutions the display supports, to allow
the computer to auto-configure a compatible resolution (presuming one
has "auto-configure" turned on in one's OS).

Now, while the EDID signal technically makes the cable bi-directional,
99.99999% of the information transfer is uni-directional because the
EDID signal is typically only transmitted from the display to the
computer once, at initialization (or at display plug-in) time.

If you dislike the EDID web page (and you are also free to dislike that
page, but your dislike does not change the accuracy of the information
provided thereupon), try looking up EDID on Wikipedia instead, where
the EDID page
(http://en.wikipedia.org/wiki/Extended_display_identification_data)
says this as its first sentence:

    Extended display identification data (EDID) is a data structure
    provided by a digital display to describe its capabilities to a
    video source (e.g. graphics card or set-top box).

The only way that this "structure" can be "provided by ... a ...
display" ... "to a video source" is with a return data channel in the
video cable running _from_ the display _to_ the video source.

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Re: Hk Cqvst wrote: nVidia + gamma !FIXED! not.socialnetwork@gmail.com - 2015-01-19 13:43 +0000
  Re: Hk Cqvst wrote: nVidia + gamma !FIXED! Rich <rich@example.invalid> - 2015-01-19 17:32 +0000
    Re: Hk Cqvst wrote: nVidia + gamma !FIXED! Avoid9Pdf@gmail.com - 2015-01-20 18:47 +0000
      Re: Hk Cqvst wrote: nVidia + gamma !FIXED! Jerry Peters <jerry@example.invalid> - 2015-01-20 21:16 +0000
        Re: Hk Cqvst wrote: nVidia + gamma !FIXED! Unknown <dog@gmail.com> - 2015-01-21 11:59 +0000
          Re: Hk Cqvst wrote: nVidia + gamma !FIXED! Rich <rich@example.invalid> - 2015-01-21 12:17 +0000
            Re: Hk Cqvst wrote: nVidia + gamma !FIXED! no.top.post@gmail.com - 2015-01-27 19:25 +0000
          Re: Hk Cqvst wrote: nVidia + gamma !FIXED! Jerry Peters <jerry@example.invalid> - 2015-01-21 21:18 +0000
      Re: Hk Cqvst wrote: nVidia + gamma !FIXED! "David W. Hodgins" <dwhodgins@nomail.afraid.org> - 2015-01-20 16:50 -0500

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