这是我写的一个画线的宏！！但只可以调用一次，第二次调用就发生错误，怎么修改啊？
程序如下：
line MACRO x,y,z,col
;pusha
MOV CX,x
MOV DX,y
ZZ1:
MOV BH,0
MOV AL,col
MOV AH,0ch
INT 10h
INC CX
CMP CX,z
JNZ ZZ1
;popa
ENDM
data SEGMENT
ok DB ?
data ENDS
code SEGMENT
ASSUME CS:code,DS:data
main:
MOV AX,data
MOV DS,AX
MOV AH,0
MOV AL,12h
INT 10h
line 30,80,70,2h
；line 40,90,70,04dh
MOV AH,01h
INT 21h
MOV AH,4ch
INT 21h
code ENDS
END main
