P5 EQU 0F8H
P7 EQU 0DBH


ORG 0


START:
   LCALL READ_KEYS
   LCALL COUNT_ONES
   CPL A
   MOV P1, A
   SJMP START


;-------------------------------------------------
; USTAWIA AKUMULATOR W ZALEZNOSCI OD WCISNIETYCH KLAWISZY I PRZYCISKOW
;---------------------------------------------------
READ_KEYS:
    MOV A, #70H
    ANL P5, #0FH
    ORL P5, A

    MOV A, P7
    CPL A
    ANL A, #0FH
    MOV R0, A

    MOV A, P3
    CPL A
    RL A
    RL A
    ANL A, #0F0H
    ADD A, R0
    RET

;-------------------------------------------------
; ZLICZA JEDYNKI W AKUMULATORZE
;---------------------------------------------------

COUNT_ONES:
    MOV R1, #0
LOOP_COUNT:
    JZ END_COUNT
    RRC A
    JNC LOOP_COUNT
    INC R1
    CLR ACC.7

END_COUNT:
    MOV A, R1
    RET

END