sr71.asm

这是汇编基本的程序主要是熟悉汇编的语法

STACK   SEGMENT  STACK
        DW       64 DUP(?)
STACK	ENDS
CODE	SEGMENT
	ASSUME  CS:CODE
START:  CLI
	PUSH    DS
	MOV	AX,0000H
	MOV	DS,AX
	MOV	AX,OFFSET	IRQ7
	ADD	AX,2000H
	MOV	SI,003CH
	MOV	[SI],AX
	MOV	AX,0000H
	MOV	SI,003EH
	MOV	[SI],AX
	POP	DS
	IN	AL,21H
	AND	AL,7FH
	OUT	21H,AL
	MOV	CX,000AH
	STI
A1:	JCXZ	A2
	HLT
	JMP 	A1
A2:	IN	AL,21H
	OR	AL,80H
	OUT	21H,AL
A3:	JMP	A3
IRQ7:	MOV	AX,0137H
	INT	10H
	DEC	CX
	MOV	AL,20H
	OUT	20H,AL
	IRET
CODE	ENDS
	END	START