DOS ain't dead

HX/OGLTEST error (Users)

posted by Doug , 26.05.2011, 22:40

> Interesting. It's still a bit "unusual" that the program fails, because
> VESA32 clears the buffer at ES:DI with zeros before its int 10h, ax=4F01h
> call. This means, although your VESA-BIOS returns with an error code, it
> modifies the buffer content!?

No -- calling with VGA video mode 3, "supported but failed" is
returned (AX = 014Fh) and the ES:DI buffer is *not* touched! (I
set the buffer up with 256 bytes of character "x" just to be
sure.)

As a check, calling with VESA mode 101h, "supported and
succeeded" is returned (AX = 004Fh) and the ES:DI buffer *is*
modified.

Later tonite, i will check these same functions on other systems
that have an Intel 845 chipset, an NVidia GeForce4 M440 card, a
NeoMagic MagicMedia 256AV chipset, and an ancient VESA 1.1 Cirrus
Logic GD5446 chipset... just to see what they do!

- Doug B.

Complete thread:

• HX/OGLTEST error - Doug, 19.05.2011, 18:37 (Users)
  • HX/OGLTEST error - Rugxulo, 19.05.2011, 22:34
    • HX/OGLTEST error - RayeR, 20.05.2011, 01:11
      • HX/OGLTEST error - Doug, 20.05.2011, 06:31
  • HX/OGLTEST error - Japheth, 20.05.2011, 06:35
    • HX/OGLTEST error - Doug, 23.05.2011, 07:54
      • HX/OGLTEST error - Japheth, 23.05.2011, 09:25
      • HX/OGLTEST error - RayeR, 23.05.2011, 19:10
        • HX/OGLTEST error - Doug, 24.05.2011, 18:55
          • HX/OGLTEST error - RayeR, 25.05.2011, 00:04
            • HX/OGLTEST error - Doug, 25.05.2011, 17:42
              • HX/OGLTEST error - RayeR, 26.05.2011, 00:48
          • HX/OGLTEST error - Japheth, 25.05.2011, 07:06
            • HX/OGLTEST error - Doug, 26.05.2011, 08:01
              • HX/OGLTEST error - Japheth, 26.05.2011, 19:26
                • HX/OGLTEST error - RayeR, 26.05.2011, 21:35
                • HX/OGLTEST error - Doug, 26.05.2011, 22:40
                  • HX/OGLTEST error - Japheth, 27.05.2011, 07:05
                    • HX/OGLTEST error - Doug, 28.05.2011, 00:51
                      • copying buffer contents to protected mode - ecm, 28.05.2011, 01:09
                      • HX/OGLTEST error - Japheth, 28.05.2011, 08:31