a9-1.asm

这个程序是掌握通过GDT表访问段的编程方法设计的。

;========================================================================
;A9-1.asm
;实验目的：	熟悉编程格式，掌握通过GDT表访问段的编程方法
;实验结果：	可以用dump命令检查数据区，验证程序的运行结果
;========================================================================
.386P
DESC		STRUC
LIMITL		DW	0
BASEL		DW	0
BASEM		DB	0
ATTR		DB	0
LIMITH		DB	0
BASEH		DB	0
DESC		ENDS

ATCE		=	98H
ATDR		=	90H
ATDW		=	92H
		
DSEG		SEGMENT USE16
GDT		LABEL   BYTE
ID1		DESC   <0FFFFH,0FFFFH,0FFH,0FFH,0FFH,0FFH>
SCODE		DESC   <0FFFFH,CSEG,,ATCE,,>
DATAS		DESC   <D1LEN,DSEG1,,ATDW,,>
DATAD           DESC   <BUFLEN-1,DSEG2,,ATDW,,>
GDTLEN	   	=   $-GDT
SCODE_SEL	=   SCODE-GDT
DATAS_SEL	=   DATAS-GDT
DATAD_SEL	=   DATAD-GDT
ID2		DESC   <0FFFFH,0FFFFH,0FFH,0FFH,0FFH,0FFH >
ID3		DESC   <0FFFFH,0FFFFH,0FFH,0FFH,0FFH,0FFH > 
DSEG		ENDS
	
DSEG1		SEGMENT USE16
BUF             DB   00H,11H, 22H, 33H, 44H, 55H, 66H, 77H 
                DB   88H,99H,0AAH,0BBH,0CCH,0DDH,0EEH,0FFH
                DB   240 DUP(0)
D1LEN           = $-1
DSEG1		ENDS

DSEG2		SEGMENT USE16 
BUFLEN          = 256
BUFFER		DB BUFLEN DUP(0)
DSEG2		ENDS

CSEG		SEGMENT USE16
                ASSUME CS:CSEG,DS:DSEG
START		PROC
		MOV AX,DATAS_SEL
		MOV DS,AX
		MOV AX,DATAD_SEL
		MOV ES,AX
		CLD
		XOR SI,SI
		XOR DI,DI
                MOV CX,32
M1:		MOVSB
		LOOP M1
		INT 0FFH
START		ENDP
CLEN		=$-1
CSEG		ENDS
END		START