Re: Loadable keyboards

[Michael Schwingen <rincewind@tubul.dascon.de>]

On Fri, Jun 19, 1998 at 07:22:20PM +0100, Petr Stehlik wrote:
> No, the Alt combinations are handled by TOS and are hardcoded, AFAIK.
> You would have to write a completely new keyboard driver.

Only up to TOS 2.06.

"New code as of 5/92: in the all-countries cases (TT, SPARROW) we use
 the new variables salttran/saltshif/saltcl as associative lookup tables
 instead of doing the alt-key translation job in code."

Keytbl (XBIOS 16) returns the pointer to the KEYTAB struct. In newer TOS
versions, these consist of:
 - unshift table
 - shift table
 - CTRL table
 - unshifted ALT table
 - shifted ALT-Table
 - capslock ALT-table

The new tables consist of scancode, ASCII code pairs, terminated by a zero
scancode.

I am not sure if this was documented by Atari (I don't have a compendium
here), and if you should use this feature to load new keytables - but I do
not see much danger in using it as long as you are sure that the TOS version
you are on does have these tables. It definitely is much easier than writing
a whole new keyboard driver.

cu
Michael
-- 
Michael Schwingen, Ahornstrasse 36, 52074 Aachen