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Re: INT 09h hooking issues

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"jacks" <jacks.1785@gmail.com> wrote in message
news:ed0143f4-3e00-4ee5-a3f1-502f78abe86e@googlegroups.com...
...

> While struggling, I came through USB keyboards. Do USB keyboard
> also emit Scan code set#1 or their scan code set that is translated(if it
> is) to scan code set#1 via USB controller on motherboard, or emulated
> otherwise.
>
> Do they have different set of Scan codes? ie other than scan code set#1.
>
> How to get scan code from usb keyboards. Is it from port 60h, or
> somewhere else?  or, somehow BIOS maps usb keyboard to emulate
> PS/2 keyboard along with scan code set#1 translation? This will allow
> to read scan code form port 60h, just as in case of PS/2 keyboard.
>

Well, I've not yet implemented a USB keyboard driver for my OS project, or
anything USB for that matter.  But, my current brief understanding of how it
works follows.  At bootup, the motherboard hardware and/or BIOS emulates a
standard port 60h/64h interface for USB keyboards and mice.  That allows old
software, like DOS and BIOS, to work with USB keyboards and USB mice.  I.e.,
if you're using DOS and aren't using USB device and driver and have a
recently made (like 2007 or later) AT compatible class machine (for BIOS
support of USB keyboards and mice), then legacy keyboard and mouse emulation
should work correctly.

If an OS like Linux or Windows enables USB support, then the OS switches the
keyboard or mouse to use USB.  Sorry, I don't know the details of that.  I
seem to recall there is a USB keyboard scancode set, but don't quote me.
This probably needs a post to alt.os.development, or you could check
osdev.org, aodfaq.wikispaces.com, etc.

Personally, I've found that USB drivers in DOS for mass storage devices,
i.e., USB harddrive and USB sticks, will _sometimes_ disable your USB
keyboard and/or mouse, or maybe the driver enables them to use USB without a
USB keyboard/mouse driver present...  I'm not sure how that works exactly.
I.e., something they do disables legacy keyboard and mouse support.

You might try to locate the four standards below.  Three of these seem to
have USB scancode or keypages.  One has minimal legacy description and
diagram showing how USB keyboards and mice are connected, but is
otherwise "thin" on detail.

"USB PC Legacy Compatibility Specification" 0.9 5/30/96
"USB HID Usage Tables" 1.12 10/28/04
"USB Device Class Definition for Human Interface Devices (HID)" 1.0 1997
"USB HID to PS/2 Scan Code Translation Table" 2004 MS Corp.


Rod Pemberton

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Thread

INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-08 07:52 -0700
  Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-08 20:49 -0400
    Re: INT 09h hooking issues pete@nospam.demon.co.uk - 2012-08-09 05:32 +0000
      Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-09 04:39 -0400
        Re: INT 09h hooking issues Bogus@Embarq.com (Steve) - 2012-08-09 11:44 +0000
          Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-09 20:09 -0400
            Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-09 23:20 -0700
              Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-10 04:26 -0400
                Re: INT 09h hooking issues Bogus@Embarq.com (Steve) - 2012-08-10 12:08 +0000
                Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-11 23:10 -0700
                Re: INT 09h hooking issues pete@nospam.demon.co.uk - 2012-08-12 07:18 +0000
                Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-12 04:29 -0400
                Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-14 05:40 -0700
                Re: INT 09h hooking issues Jim Leonard <MobyGamer@gmail.com> - 2012-08-14 08:29 -0700
                Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-15 20:14 -0700
                Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-14 05:30 -0700
                Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-12 04:01 -0400
        Re: INT 09h hooking issues pete@nospam.demon.co.uk - 2012-08-10 05:27 +0000
      Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-09 08:41 -0700
        Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-09 19:54 -0400
          Re: INT 09h hooking issues jacks <jacks.1785@gmail.com> - 2012-08-10 00:11 -0700
            Re: INT 09h hooking issues "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-08-10 04:27 -0400

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