Date: Mon, 16 Jan 1995 16:34:51 +0100 (MET) From: j@uriah.sax.de (J Wunsch) To: wpaul@skynet.ctr.columbia.edu (Wankle Rotary Engine) Cc: freebsd-hackers@FreeBSD.org Subject: Re: serial consoles and keyboard probes Message-ID: <199501161534.QAA02863@bonnie.tcd-dresden.de> In-Reply-To: <199501160626.BAA03730@skynet.ctr.columbia.edu> from "Wankle Rotary Engine" at Jan 16, 95 01:26:09 am
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As Wankle Rotary Engine wrote:
|
| - Merged biosboot and serialboot -- the keyboard i/o routines and the
| serial port i/o routines are contained in the same boot block: putchar()
| writes to both the serial port and the standard graphics display, and
| getchar() can be told to read either from the serial port of the
| PC's keyboard.
Two problems i'm seeing here: i had already a hard job to even fit the
serial boot stuff w/o VGA/kbd BIOS into the existing boot blocks.
Having both there would bloat them again, and space is really a scarce
resource.
Second: assume sio0 is connected to a modem. Since the bootblocks
would then echo all their neat garbage to the modem, too, the modem
might get confused. Consider the case the user on the keyboard hits
``?'' to see the file list, and on of the files has the nifty name
``atd2345''... :-)
The above aside: i like the idea.
...
| What I need to know is this:
|
| - Is there a way to read the 'keyboard installed/not installed' flag
| from the CMOS configuration, or is there some probe routine in the
| BIOS that would allow you to reliably detect the presence or absence
| of the keyboard?
In general: no. But if you intend to have a keyboard connected only
sometimes, simply tell your BIOS ``keyboard not installed'' (how do
you do this? arrrg, you certainly need a keyboard for this:-). This
flag simply means: ``Hey BIOS!, don't care if there's no keyboard at
all!''. If you nevertheless happen to have a keyboard connected, it
will be initialized as usual.
I'm not sure if there's BIOS support to probe for the existance of a
keyboard, at least, the keyboard controller can tell you if you ask
it.
Btw., most BIOSses will not allow you to run without a graphics board
installed (AMI the only exception i know of), so you always have to
waste a slot for this bugger.
--
cheers, J"org work: --- no longer ---
private: joerg_wunsch@uriah.sax.de
Never trust an operating system you don't have sources for. ;-)
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