8086霓虹灯仿真出错，有大佬帮忙看看问题吗？

DATA SEGMENT
IOPORT  EQU 0D880H-280H
IO8255A EQU IOPORT+280H
IO8255B EQU IOPORT+281H
IO8255C EQU IOPORT+282H
IO8255T EQU IOPORT+283H
MESS    DB  'PLEASE ENTER ANY KEY WHEN READY!',0DH,01H,'$'
DATA ENDS
STACK SEGMENT
STA DW 50 DUP(?)
STACK ENDS
CODE SEGMENT
        ASSUME CS:CODE,DS:DATA,ES:DATA,SS:STACK
START:   MOV  AX,DATA
        MOV  DS,AX
        MOV  ES,AX
        MOV  AH,09H
        MOV  DX,OFFSET MESS
        INT  21H
        MOV  AH,01H
        INT  21H
        MOV  DX,IO8255T
        MOV  AL,80H
        OUT  DX,AL
LOP1:   MOV  CX,03H
        MOV  DX,IO8255A
        MOV  AL,80H
        PUSH CX
        MOV  CX,0AH
LOP2:   OUT  DX,AL
        SAR  AL,1
        LOOP LOP2
        POP  CX
        INC  DX
        DEC  CX
        JNZ  LOP1
LOP3:   MOV  CX,03H
        MOV  DX,IO8255A
        MOV  AL,80H
        PUSH CX
        MOV  CX,0AH
LOP4:   OUT  DX,AL
        SHR  AL,1
        LOOP LOP4
        POP  CX
        INC  DX
        DEC  CX
        JNZ  LOP3
LOP5:   MOV  CX,03H
        MOV  DX,IO8255A
        MOV  AL,80H
        PUSH CX
        MOV  CX,0AH
LOP6:   OUT  DX,AL
        MOV  DL,03H
        SHR  AL,1
        LOOP LOP6
        POP  CX
        INC  DX
        DEC  CX
        JNZ  LOP5
LOP7:   MOV  CX,04H
        MOV  DX,IO8255A
        MOV  AL,80H
        PUSH CX
        MOV  CX,03H
LOP8:   OUT  DX,AL
        SHR  AL,1
        LOOP LOP8
        POP  CX
        INC  DL
        DEC  CX
        JNZ  LOP7
        MOV  AH,06H
        MOV  DL,0FFH
        INT  21H
        JNZ  LOP9
        JMP  LOP1
LOP9:   MOV  AX,4C00H
        INT  21H
CODE    ENDS
END    START



```![图片说明](https://img-ask.csdn.net/upload/201912/23/1577113587_581057.png)