asm.txt

芯片8259驱动程序

STACK   SEGMENT STACK
	         DW 64 DUP(?)
STACK   ENDS
CODE    SEGMENT
ASSUME CS:CODE
START:	MOV BX,3000H     ；源数据串首址
	MOV DX,0E010H
	MOV CX,0010H     ；待传送字节个数
	MOV AL,80H       ；0000方式0，A口输出，B口输出，C口输出
	OUT 63H,AL       ；8255控制寄存器
A1:	MOV AL,DH        ；11000000
	OUT 62H,AL       ；C口
	MOV AL,DL
	OUT 61H,AL       ；B口
	MOV AL,[BX]
	OUT 60H,AL       ；A口
	MOV AL,0CH       ；PC6复位清零
	OUT 63H,AL       ；8255控制寄存器
	MOV AL,0DH       ；00001101  PC置位变1
	OUT 63H,AL
	INC BX
	INC DX
	LOOP A1
MOV AL,90H       ；10010000  方式口，A口输入，B口输出，C口输出
	OUT 63H,AL
	MOV BX,3000H
	MOV CX,0010H     ；传送个数
	MOV DX,0E010H
	MOV SI,4000H     ；目的地址
A2:	MOV AL,DH
	OUT 62H,AL       ；C口
	MOV AL,DL
	OUT 61H,AL       ；B口
	MOV AL,0EH       ；00001110   PC7复位清零
	OUT 63H,AL       ；8255控制寄存器
	IN AL,60H        ；读入A口
	MOV [SI],AL
	CMP AL,[BX]
	JNZ A4
	MOV AL,0FH
	OUT 63H,AL
	INC SI
	INC BX
	INC DX
	LOOP A2
	MOV AX,014FH     ；显示“0”   
	INT 10H
	MOV AX,014BH     ；显示“K”
	INT 10H
A3:	JMP A3
A4:	MOV AX,0145H     ；显示“E”
	INT 10H
A5:	JMP A5
CODE  ENDS
         END START