Date   : Wed, 30 Jun 2010 22:08:24 +0100
From   : jgh@... (J.G.Harston)
Subject: BBC Master Compact key ghosting

samwise wrote:
> "Which brings me back to my original question - how does the 6502/MOS
> combo behave?

See the commented OS 1.20 disassembley at http://mdfs.net/Docs/Comp/BBC/OS1-20
The code in the BBC MOS from &EF02 onwards shows how the firmware
interrogates the keybaord and deals with n-key rollover and elimiating
ghosting. The code from EF16 to EF4D is called on the keyboard timer
interupt to check for continued and further keypresses.

('ghosting' is a new phrase, I can't remember what it's usually called.)

JGH