Add and Print two digit number

.MODEL SMALL
.STACK 100

.DATA

    NUM1 DB ?
    NUM2 DB ?
    RESULT DB ?
    MSG1 DB "ENTER FIRST NUMBER TO ADD : $"
    MSG2 DB 10,13,"ENTER SECOND NUMBER TO ADD : $"
    MSG3 DB 10,13,"RESULT OF ADDITION : $"

.CODE

MAIN PROC

    MOV AX, @DATA
    MOV DS, AX

    LEA DX, MSG1
    MOV AH, 9
    INT 21H

    MOV AH, 1
    INT 21H
    SUB AL, 30H
    MOV NUM1, AL

    LEA DX, MSG2
    MOV AH, 9
    INT 21H

    MOV AH, 1
    INT 21H
    SUB AL, 30H
    MOV NUM2, AL

    ADD AL, NUM1            ; ADDING TWO NUMBERS NUM1 AND ACCUMALOTOR VALUE WHICH HAVE THE NUM2 VALUE

    MOV RESULT, AL

    MOV AH, 0               ; REMOVE GARBAGE FROM AH ( ACCUMALATOR HIGH )
    AAA                     ; What AAA exactly does is it converts the result into BCD form and first digit is saved in
                            ; AH register and second digit is saved in AL register.

    ADD AH, 30H             ; By adding 30H to BCD will Convert it to ASCII code which will print the digit (number) on screen.
    ADD AL, 30H

    MOV BX, AX              ; Since the AH register is used again and again. We cannot lose the result in AH and AL register,
                            ; So to save the to be printed value in BH and BL register. By moving AX to BX.

    LEA DX, MSG3
    MOV AH, 9
    INT 21H

    MOV AH, 2               ; OUTPUT FIRST CHARACTER ON BASE REGISTOR
    MOV DL, BH              ; PRINT BASE REGISTOR HIGHER PORTION ( BH )
    INT 21H

    MOV AH, 2               ; OUTPUT FIRST CHARACTER ON BASE REGISTOR
    MOV DL, BL              ; PRINT BASE REGISTOR LOWER PORTION ( BL )
    INT 21H

    MOV AH, 4CH
    INT 21H

MAIN ENDP
ENDS PROC