
        NAM     NOKEY
        
***     [Sub]routine that makes a bounce-free
*       check that no keys are activated
*       by scanning keypad or keyboard #MANY
*       times in succession.
*       Utilizes subroutine WCHKEY.
*
*       Version 1.0
*       hjoel 1987-12-21
*
*       Exit:   $FF in AccA.
***
                
WCHKEY  EQU     $A001

MANY    EQU     $A0             No. of key-scan loops.
ALLUP   EQU     $FF             Keypad-value when
*                               all keys are up.

        ORG     $A040
NOKEY   LDB     #MANY
SPINN   JSR     WCHKEY
        CMPA    #ALLUP
        BNE     NOKEY 
        DECB
        BNE     SPINN
        RTS        
        END     NOKEY
