String Character Case Conversion ALP - 8086

.model small
.stack
.data
msg db "DeepRaj$"
.code
main proc
    mov ax,@data
    mov ds,ax
    lea si,msg
    again:mov al,[si]
    cmp al,'$'
    je final
    xor al,32
    mov [si],al
    inc si
    jmp again
    final:mov [si],'$'
    mov dx,offset msg
    mov ah,9
    int 21h
    mov ah,4ch
    int 21h
main endp
end main