; Assembly code for printing from 0 to 99 in double segment display

ORG 00H                 ; Set origin to 00H

MOV DPTR, #300H         ; Moving Data pointer to 300H
MOV R0, #10D            ; Loop 10 times
MOV R7, #0D             ; Loop variable will increment

LOOP1:                  ; Loop of printing [0-9] of right digit
    ; Loop 1 : loops to the position where the next value is present
    MOV DPTR, #300H
    MOV A, R7
    MOV R6, A
    MOV A, R7

    JZ PASS             ; Jump if value of A (which is R7) is zero
    LOOP3:
        INC DPTR
        DJNZ R6, LOOP3
    PASS:

    ; Passing value of DPTR in output pin P2 (for left segment)
    INC R7
    MOV A, #00H
    MOVC A, @ A+DPTR
    MOV P2, A

    ; Loop 2 : loops to the position [0-9]
    MOV R1, #10D
    MOV DPTR, #300H
    LOOP2:
        MOV A, #00H
        MOVC A, @ A+DPTR
        MOV P0, A           ; Passing output to right segment
        LCALL DELAY         ; Note that P0 has segment pins from
        INC DPTR            ; higher to lower order
        DJNZ R1, LOOP2

    ;INC DPTR
    DJNZ R0, LOOP1

DELAY:                               ; Delay procedure
    MOV R2, #10
    RAI:
        MOV R3, #255
    RA:
        MOV R4, #255
    JA:
        DJNZ R4, JA
        DJNZ R3, RA
        DJNZ R2, RAI
    RET

ORG 300H
DB 0C0H  ; digit drive pattern for 0
DB 0F9H  ; digit drive pattern for 1
DB 0A4H  ; digit drive pattern for 2
DB 0B0H  ; digit drive pattern for 3
DB 099H  ; digit drive pattern for 4
DB 092H  ; digit drive pattern for 5
DB 082H  ; digit drive pattern for 6
DB 0F8H  ; digit drive pattern for 7
DB 080H  ; digit drive pattern for 8
DB 090H  ;digit drive pattern for 9
END