擴充中斷控制器8259（實驗四）

實驗目的

1.掌握中斷控制器8259管理

2.掌握擴充中斷

實驗原理

ASM 彙編代碼

;8259-1.asm
;8259中斷查詢方式應用實驗

;*****************************************************************
;         8259中斷查詢
;*****************************************************************
I8259_1  EQU   2B0H       ;8259的ICW1端口位址
I8259_2  EQU   2B1H       ;8259的ICW2端口位址
I8259_3  EQU   2B1H       ;8259的ICW3端口位址
I8259_4  EQU   2B1H       ;8259的ICW4端口位址
O8259_1  EQU   2B1H       ;8259的OCW1端口位址
O8259_2  EQU   2B0H       ;8259的OCW2端口位址
O8259_3  EQU   2B0H       ;8259的OCW3端口位址

data segment
 
 mes1 db 'you can play a key on the keyboard!',0dh,0ah,24h
 mes2 dd  mes1
 mess1 db 'Hello! This is interrupt    *  0  *!',0dh,0ah,'$'
 mess2 db 'Hello! This is interrupt    *  1  *!',0dh,0ah,'$'
 mess3 db 'Hello! This is interrupt    *  2  *!',0dh,0ah,'$'
 mess4 db 'Hello! This is interrupt    *  3  *!',0dh,0ah,'$'
 mess5 db 'Hello! This is interrupt    *  4  *!',0dh,0ah,'$'
 mess6 db 'Hello! This is interrupt    *  5  *!',0dh,0ah,'$'
 mess7 db 'Hello! This is interrupt    *  6  *!',0dh,0ah,'$'
 mess8 db 'Hello! This is interrupt    *  7  *!',0dh,0ah,'$'
data ends

stacks segment
 db 100 dup(?)
stacks ends
STACK1 SEGMENT STACK
        DW 256 DUP(?)
STACK1 ENDS

CODE SEGMENT
        ASSUME CS:CODE,DS:DATA,SS:stacks,ES:DATA
START: mov ax,data
       mov ds,ax
       mov es,ax
       mov ax,stacks
       mov ss,ax

       MOV  DX,I8259_1			;初始化8259的ICW1
       MOV  AL,13H				;邊沿觸發、單片8259、需要ICW4
       OUT  DX,AL

       MOV  DX,I8259_2			;初始化8259的ICW4
       MOV  AL,0B0H				;非自動結束EOI
       OUT  DX,AL
       MOV  AL,00H
       OUT  DX,AL
       MOV  AL,03H
       OUT  DX,AL

       MOV  DX,O8259_1			;初始化8259的OCW1
       MOV  AL,00H				;打開IR0和IR1的屏蔽位
       OUT  DX,AL
      
QUERY: MOV  AH,1				;判斷是否有按鍵按下
       INT  16H
       JNZ  QUIT				;有按鍵則退出

       MOV  DX,O8259_3			;向8259的OCW3發送查詢指令
       MOV  AL,0CH
       OUT  DX,AL

       IN   AL,DX				;讀出查詢字
       MOV  AH,AL
       AND  AL,80H
       TEST AL,80H				;判斷中斷是否已響應
       JZ   QUERY				;沒有響應則繼續查詢
       MOV  AL,AH       
       AND  AL,07H
       CMP  AL,00H
       JE   IR0ISR				;若為IR0請求，跳到IR0處理程式
       CMP  AL,01H
       JE  IR1ISR				;若為IR1請求，跳到IR1處理程式
       CMP  AL,02H
       JE   IR2ISR
       CMP  AL,03H
       JE   IR3ISR
       CMP  AL,04H
       JE   IR4ISR
       CMP  AL,05H
       JE   IR5ISR
       CMP  AL,06H
       JE   IR6ISR
       CMP  AL,07H
       JE   IR7ISR
       JMP  QUERY

 

IR1ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess2	;顯示提示資訊
        MOV AH,09
        INT 21H
        JMP  EOI

IR2ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess3	;顯示提示資訊
        MOV AH,09
        INT 21H
        JMP  EOI
IR3ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess4	;顯示提示資訊
        MOV AH,09
        INT 21H
        JMP  EOI
IR4ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess5	;顯示提示資訊
        MOV AH,09     
        INT 21H
        JMP  EOI
IR5ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess6    ;顯示提示資訊
        MOV AH,09
        INT 21H
        JMP  EOI
IR6ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess7     ;顯示提示資訊
        MOV AH,09
        INT 21H
        JMP  EOI
IR7ISR: MOV AX,DATA
        MOV DS,AX
        MOV DX,offset mess8     ;顯示提示資訊
        MOV AH,09
        INT 21H

EOI:  
       MOV  DX,O8259_2          ;向8259發送中斷結束指令
       MOV  AL,20H
       OUT  DX,AL
       JMP  QUERY
       
QUIT:  MOV  AX,4C00H            ;結束程式退出
       INT  21H


CODE ENDS
     END START