MOV DX,211H;ICW2初始化
MOV AL,08H;初始化中斷類型碼范圍,08-0F對應INT0-INT7
OUT DX,AL
MOV DX,211H;ICW4初始化
MOV AL,01H;
OUT DX,AL
;--------------打開中斷--------------
MOV DX,211H;打開8259A八號中斷
IN AL,DX
AND AL,0FEH;1111 1110
OUT DX,AL
STI;開CPU中斷,IF=1
MOV BX,OFFSET NUM;取控制信號的偏移地址
MOV SI,0 ;將SI循環歸零
LOP: MOV AX,0
JMP LOP;死循環,等待中斷到來
;------------中斷程序開始----------
INTP PROC FAR;
LTP: MOV DX,219H
MOV AL,[BX+SI]
OUT DX,AL
INC SI
CMP SI,04H
JNZ NEXT
MOV SI,0