Date   : Fri, 23 Sep 1994 22:45:36 +0100 (BST)
From   : clr1@...
Subject: Pinching PC interrupts

I'm trying to implement my PC keyboard handling, and I'm having immense 
difficulty hitching onto interrupts. I'm using int21 functions 35h and 
25h I think, and they seem to be working okay but my piggy-back jump isn't.

I've stored the previous interrupt address in two word variables, which 
are contiguous in memory. I then do one of the following to continue 
execution, none of which work...

jmp [@...]
jmp far ptr [@...]
jmp far ptr word ptr [@...]
jmp far ptr [word ptr [offset @kbdofs]]

etc...

which one is right?!? I'm at my wits end; BP is a real sod when it comes 
to this kind of thing.

+-------------------+-------------------------------------------------+
| /-- |_| /-- | (~  | "And the driving is like the driving of Jehu,   |
| \-- | | |   | _)  | the son of Nimshi, for he drives furiously."    |
+-------------------+-------------------- Second Book of Kings 9 v20 -+
|  Wanted: 486DX2-66 VLB M/board; VLB graphics card; SBpro soundcard  |
+---------------------------------------------------------------------+