82592.asm

汇编课程设计

main0 equ 20h
main1 equ 21h
sub0 equ 0a0h
sub1 equ 0a1h
DATA SEGMENT
        MESS1 DB 'THIS IS A 8259 INTR',0Ah,0Dh,'$'
        MESS2 DB 'ENTER ANY KEY TO EXIT TO DOS',0Ah,0Dh,'$'
	YANMA1 DB ?
	YANMA2 DB ?
DATA ENDS
;STACKS SEGMENT
;sta        DW 100 DUP(?)
;STACKS ENDS
CODE SEGMENT
        ASSUME CS:CODE,DS:DATA;,SS:STACKS
START:  
	MOV AX,DATA
	MOV DS,AX
       ; MOV AX,STACKS
       ; MOV SS,AX

        CLI;关中断
        MOV  AH,35H
        MOV  AL,72H  ;取72H号中断向量送 ES：BX
        INT   21H
        PUSH  ES        ;保存原中断向量
        PUSH  BX
        PUSH  Ds
        MOV  DX,SEG  INTR_proc
        MOV  DS,DX
        MOV  DX,OFFSET  INTR_proc ;设置新的中断向量
        MOV  AH,25H
        MOV  AL,72H
        INT  21H
        POP  DS

        MOV DX,  main1 ;主片允许中断
        IN  AL,  DX  
        MOV YANMA1,AL            
        AND  AL,   11111011B
        OUT   DX,  AL
        MOV DX,sub1
        IN  AL, DX 
        MOV YANMA2,AL             ;从片允许中断
        AND  AL,   11111011B
        OUT   DX,  AL

        MOV DX,OFFSET MESS2;显示提示信息
	MOV AH,09H
	INT 21H

        MOV  DX, 0D400H+68H    ;9054的I/O起始地址及中断使能寄存器的偏移地址
        IN   AX, DX
        OR   AX,0900H         ;设置中断允许
        OUT  DX, AX
  
        MOV BX,0ah;设置中断次数为10
        STI;开中断
LL:     CMP BX,0
        JE EXIT
        MOV     AH,     01H;判断有无键按下
        INT     16H   
        JNZ EXIT
        JMP LL
;;WW为可选
;;WW:     
; ;       JMP WW ;等中断
 ; ;      JMP LL
exit1:mov ax,4c00h
        int 21h
EXIT:   MOV  DX, 0D400H+68H    ;9054的I/O起始地址及中断使能寄存器的偏移地址
        IN   AX, DX
        OR   AX,0F7FFH         ;中断禁止
        OUT  DX, AX


        MOV DX,  main1 ;恢复掩码
        MOV AL,YANMA1
        OUT   DX,  AL
        MOV DX,sub1
        MOV AL,YANMA2
        OUT   DX,  AL
	
        POP DX;?
        POP DS  ;恢复原中断向量
       MOV  AH,25H
        MOV  AL,72H
        INT  21H


        MOV AH,4CH
        INT 21H
  
INTR_proc proc far
       push ax
 ;      push dx
        CLI
        DEC BX
     
        MOV DX,OFFSET MESS1
        MOV AH,09H
       INT 21H

	
        MOV DX,sub0;发中断结束命令
        MOV AL,20H
        OUT DX,AL
        mov dx,main0
        out dx,al
  ;      pop dx
        pop ax
        STI
        IRET
intr_proc endp
CODE ENDS
END START