Here my code :

T dw 2,3,1,2,3,4,0,0,8,0,7,0,8,7 
mov [200h], [T]
mov si,0
mov di,0
mov n, 14 
call count_null
mov [400h], di
ret

count_null: 
   cmp si, n
   je fin
   cmp [T+si], 0
   jne etq1
   inc di
 etq1:
   inc si
   jmp count_null
 fin:
       

ret