汇编语言编写累加程序怎么写?

dseg segment
num db 2,5,10,25
sum db ?
tab db '0123456789ABCDEF'
str db ?,?,'H',0ah,0dh,'$'
dseg ends
cseg segment
assume cs:cseg,ds:dseg
begin:
mov ax,dseg
mov ds,ax
xor al,al
lea si,num
mov cx,4
next:
add al,[si]
inc si
loop next
mov sum,al
lea bx,tab
mov dh,al
mov cl,4
shr al,cl
xlat
mov str,al
mov al,dh
and al,0fh
xlat
mov str+1,al
lea dx,str
mov ah,9
int 21h
mov ah,4ch
int 21h
cseg ends
end begin