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    SubjectRe: [PATCH] Default keyboard LEDs
    Samuel Thibault wrote:
    > In many cases, one prefers to have e.g. the NumLock on by default. In
    > many cases, one doesn't want to have it by default, e.g. on laptops.
    > Distributions actually have a very hard time trying to set this
    > correctly after the kernel boot, and that doesn't work for new consoles
    > that are created via the openvt(1) command anyway. This hence adds a
    > keyboard.default_leds boot parameter that permits to configure the
    > default keyboard LEDs.
    > Signed-off-by: Samuel Thibault <>
    > Actually, what would be perfect would be to use the configuration that
    > the BIOS sets at boot by default. That is device-dependent, however.

    It is, but it can be read out either by INT calls at initialization
    time, or by reading out the byte at physical address 0x417:

    MEM 0040h:0017h - KEYBOARD - STATUS FLAGS 1
    Size: BYTE
    SeeAlso: MEM 0040h:0018h,INT 16/AH=02h,MEM 0040h:0096h

    Bitfields for keyboard status flags 1:
    Bit(s) Description (Table M0010)
    7 INSert active
    6 Caps Lock active
    5 Num Lock active
    4 Scroll Lock active
    3 either Alt pressed
    2 either Ctrl pressed
    1 Left Shift pressed
    0 Right Shift pressed
    SeeAlso: #M0011,#00587

    The same information is available through INT 16h, AH=02h.


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