A83: Direct Input...

To: assembly-83@lists.ticalc.org
Subject: A83: Direct Input...
From: Ian Graf <ian_graf@geocities.com>
Date: Fri, 03 Apr 1998 23:39:11 -0800
Delivered-To: assembly-83-outgoing@towerguard.unix.edu.sollentuna.se
Reply-To: assembly-83@lists.ticalc.org


Say I have This bit of code to wait for 2nd to be pressed

     wait_for_2nd:

          ld a,0ffh            ; Reset the keyport
          out (1),a
          ld a,0bfh            ; Enable the row with 2nd
          out (1),a
          in a,(1)
          cp k2nd              ; Check for 2nd
          jp nz,wait_for_2nd   ; if not pressed re-loop
          ret                  ; else return

but, if I call it twice in a row, the second call returns Immediately.
The strange thing is that I thought a key press would be prevented
from being read twice. Why does the same press of 2nd get read twice,
and how can I prevent it?

Ian Graf
ian_graf@geocities.com

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