小弟最近要用8253发脉冲，写了一段代码，可是发出的脉冲有问题！哪位大侠可以看看，帮我个忙啊！

感激不尽！

代码如下：

DATA     SEGMENT

TS       DW   6000

DATA     ENDS


   ESTACK  SEGMENT  STACK
       DB 1000 DUP(0)
   ESTACK    ENDS

   CODE  SEGMENT
      ASSUME CS:CODE, DS:DATA, SS:ESTACK
MAIN PROC FAR
      MOV DX, 301H              ;步进电机加使能
      MOV AL, 01H
      OUT DX,AL
      MOV CX,10000
      CALL WAITF

   PUBLIC  INT00
   PAGE
   INT00    PROC NEAR        ;保存旧的08H中断向量入口地址
       PUSH DS
       CLI
       CLD
       MOV AX,0000H
       MOV DS,AX
       MOV SI,0020H
    LODSW
       MOV BX,AX
       LODSW
       POP DS
       PUSH AX
       PUSH BX
       PUSH ES
       MOV AX,DATA         ;设置新的08H中断向量入口地址
       MOV DS,AX
       MOV AX,0000H
       MOV ES,AX
       MOV DI,0020H
       MOV AX,OFFSET TIMER0
       STOSW
       MOV AX,CS
       STOSW
       POP ES
       MOV AL,36H         ;写入中断控制字
       OUT 43H,AL         
       MOV AX,TS         ；初始化8253定时器
       OUT 40H,AL
       MOV AL,AH
       OUT 40H,AL
       IN AL,21H
       PUSH AX
       AND AL,0FCH
       OUT 21H,AL
       STI



;********************************************************************;***************************

*****************************************



       CLI
       CLD
POP AX
OUT 21H,AL
       MOV AL,36H         ;恢复旧的定时器初值
       OUT 43H,AL         ;恢复中断服务程序的入口地址
       MOV AL,0
       OUT 40H,AL
       OUT 40H,AL
       MOV AX,0
       MOV ES,AX
       MOV DI,4*8
       POP AX
       STOSW
       POP AX
       STOSW
       STI

;close the 'x' enable
MOV DX,301H                                     ；关闭步进电机使能
MOV AL,00H
OUT DX,AL

       RET
   INT00    ENDP


   PUBLIC TIMER0         ;新的中断服务子程序
   PAGE
   TIMER0    PROC NEAR
       PUSH DS
       PUSH ES
       PUSH AX
       PUSH BX
       PUSH CX
       PUSH DX
       MOV AX,DATA
       MOV DS,AX
       MOV ES,AX
;out  one +x  pulse to the I/O

G00_X:            

      MOV DX,300H        ;向步进电机发脉冲(基地址＝300H,0位＝脉冲，1位＝方向)
      MOV AL,01H
      OUT DX,AL
      MOV CX,1
      CALL WAITF
      MOV AL,00H
      OUT DX,AL

G00_END:              MOV AL,20H
       OUT 20H,AL
       POP DX
       POP CX
       POP BX
                      POP AX
       POP ES
       POP DS
       STI
       IRET
TIMER0   ENDP


WAITF  PROC  NEAR         ;普通的延时子程序
   PUSH AX
WAITF1:
   IN AL,61H
   AND AL,10H
   CMP AL,AH
   JE WAITF1
   MOV AH,AL
   LOOP WAITF1
   POP AX
   RET
WAITF  ENDP

MAIN ENDP
CODE ENDS
END MAIN