scaling question

From: Pablo (nospam_at_yahoo.com)
Date: 07/17/05

  • Next message: J.O. Aho: "Re: scaling question" 
    Date: Sun, 17 Jul 2005 06:03:27 GMT

    Hi,

    Our in-house made PC has TFT panel Sharp LQ150X1LGN2A attached to MoBo via
    LVDS.
    Panel's resolution is 1024x768, video chip - C&T 69000. BIOS video is set to
    1024x768. X server
    is XFree86 3.3.0, XF86Config uses 800x600 modeline (Modeline "800x600" 36
    800 824 896 1024 600 601 603 625).
    No window manager, just X server and xv app to display some image. When X
    starts even though
    it's set to 800x600 it displays weave pattern full-screen, 1024x768. If I
    run 'xv 800x600.jpg',
    it also displays 800x600 image full-screen. Also, if I run xv to display
    1024x768 image
    on 800x600 X, it is shown complete, full-screen.

    Now the question... I'm not that familiar with how video works so it might
    sound silly
    but here it goes - what does the scaling? Is it video driver? Some other X
    component,
    BIOS? From X log:
    (--) SVGA: CHIPS: TFT probed.
    (--) SVGA: CHIPS: Display Size: x=1024; y=768

    I assume it is ct69000 video driver somehow queries panel's resolution, gets
    1024x768
    value vs. config's 800x600 and makes chip to scale everythings that X sends
    to it to
    1024x768. Am I correct?

    Thank you,

    Pavel.

  • Next message: J.O. Aho: "Re: scaling question"

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