[Oberon] Keyboard input in ETH Oberon.

[peter at easthope.ca]

Hi,

ETH Oberon Input.Mod of is visible in the screenshot at 
http://easthope.ca/ETHO.Input.Mod.png . The Oberon is running on QEMU 
on Linux Debian.

In the upper viewer, ET shows some of the source for the keyboard 
translation table.

Below that Hex shows the content beginning with Oberon accents.

Questions

(1) What is achieved by "POP EAX ... RET"?

(2) What is DB?

(3) The syntax is explained as,   table = { scancode unshifted-code 
shifted-code flags } 0FFX .

Therefore scan code 1EX represents "a"; 1EX + shift represents "A"?

(4) 4X represents bit 04, flag 2?  Caps Lock effect?

(5) The first two characters under "Oberon accents" appear to be auml 
and Auml. Hex shows 83 and 80 whereas the ASCII Latin-1 Supplement 
encodes auml and Auml as E4 and C4. How does that work?

(6) Why is 0FFX necessary?

Thx,               ... P.L.


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