Wang Shuang's compilation of detection points 9.2

Completion programming, using the jcxz instruction to find the first byte with a value of 0 in the 2000H segment of the memory, after finding it,

Store its offset address in dx.

assume cs:code

code segment
start: mov ax,2000h
mov ds,ax
mov bx,0
s: mov cl, [bx]
mov ch,0
jcxz ok
inc bx
jmp short s
ok:mov dx,bx
mov ax,4c00h
int 21h
code ends
end start