Re: GGI, EGCS/PGCC, Kernel source

Kenneth Albanowski (kjahds@kjahds.com)
Fri, 27 Feb 1998 01:47:04 -0500 (EST)


On Thu, 26 Feb 1998, Michael Schmitz wrote:

> If you're really using a serial terminal, everything beyond 8 bit ASCII is
> out of the question. 8 bit ASCII can be mapped some way or other, that's an
> issue separate from the current keyboard driver (m68k style, that's what I
> happen to know). You lose any multi key combinations that way.

Yes, we mainly need a very simple "terminal" translation layer that either
sends the ASCII straight through, or munges it slightly so it matches
normal ASCII-8 (whatever we decide that is). The kernel can't see any
multi-key combinations, though user programs will be able to, via
terminfo.

> I doubt there's a way to autoprobe the connected device.

For a terminal, no, for the keyboards, there probably is. If we're lucky,
all of the relevant ones send out status messages when they wake up.

> And I'd abuse the regular keymap for the translation ...

We'll still need a separate kernel driver for each keyboard, to translate
the packets into scancodes that are translatable. Each device probably
should have its own default keymap.

> Ok, I'll focus on 'multiple keyboards' first; serial ASCII is just another
> special input driver that happens to use something other than
> handle_scancode :-)

Sounds like a good idea.

> To leave you the option of login over the serial line, I'd suggest to either
> tag the serial as 'keyboard' in the serial struct or register a new ldisc
> for it (primitive, input only).

At, interesting. Yes, a line discipline might work out well, and seems
slightly less evil then hacking the serial driver -- it could even
register itself with the console to allow the connection in the other
direction.

> Try bypassing all SCAM state and up/down processing in the keyboard handler
> for a start, and feed ASCII as 'scancode'. That should go some way (though
> it's a bad hack).
>
> I won't get to any of this before the weekend for sure, so point me in the
> right direction if I got something wrong...

You've got a better grip on it than I, I'm sure.

-- 
Kenneth Albanowski (kjahds@kjahds.com, CIS: 70705,126)

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