Sum of two single digit number

        print macro msg         lea dx,msg         mov ah,09h         int 21h     endm     read macro         mov ah,01h         int 21h     endm     .model small     .stack 100h     .data         msg1 db 10,13,'Enter the 1st number $'         msg2 db 10,13,'Enter the 2nd number $'         msg3 db 10,13,'Sum= $'     .code         mov ax,@data         mov ds,ax         ;read first number         print msg1         read         mov bl,al         ;read second number         print msg2         read         ;find sum         add bl,al         ;display sum         print msg3         mov dl,bl         sub dl,30h         mov ah,02         int 21h         mov ah,4ch         int 21h     end