Addition Of Two 4bit numbers

ASSUME CS:CODE,DS:DATA
DATA SEGMENT
	msg1 DB "Enter the first number : $"
	msg2 DB 0ah,0dh,"Enter the second number : $"
	msg3 DB 0ah,0dh,"Result :$"
DATA ENDS
CODE SEGMENT
START: MOV AX,data
	MOV DS,AX
	LEA DX,msg1
	MOV AH,09H
	INT 21H
	MOV AH,01H
	INT 21H
	SUB AL,30H
	MOV BL,AL
	LEA DX,msg2
	MOV AH,09H
	INT 21H
	MOV AH,01H
	INT 21H
	SUB AL,30H
	ADD AL,BL
	AAA
	ADD AL,30H
	LEA DX,msg3
	MOV AH,09H
	INT 21H
	MOV DL,AL
	MOV AH,02H
	INT 21H
	MOV AH,4CH
	INT 21H
CODE ENDS
END START

Output
C:\><filename.exe>
Enter the first number : 2
Enter the second number : 5
Result : 7



DosBox Commands

accessing directory
MOUNT C: ~/Downloads/masm
C:							//accesing to C

masm <filename.asm>			//compiling
link <filename.obj>
<filename.exe>				//executing file

debug <filename.exe>		//incase an error occur, debug the file
-g