l4-81.asm

汇编经典例程,是学习微机原理的好帮手,包括循环 分支等结构

DATA SEGMENT
	TOPROW  EQU  0000H
	RGTCOL  EQU  0280H
	LETCOL  EQU  0000H
	BOTROW  EQU  01E0H
	COLORF  DB ?
	COLORB  DB ?
DATA ENDS
STACK SEGMENT
	STR  DW 100 DUP(?)
STACK ENDS
CODE SEGMENT
   ASSUME DS:DATA,CS:CODE,SS:STACK
START:  MOV AX,DATA
        MOV DS,AX
	MOV AX,STACK
	MOV SS,AX
	MOV AH,0FH
	MOV BH,0
	INT 10H
	PUSH AX
	MOV AH,0
	MOV AL,12H
	INT 10H
	MOV COLORB,00H
	MOV COLORF,05H
	MOV BH,0
	MOV AH,0BH
	MOV BL,COLORB
	INT 10H
	MOV DX,200
	MOV CX,200
	MOV AH,0CH
	MOV AL,COLORF
	INT 10H
READY:	MOV AH,10H
	INT 16H
        CMP AH,01H
	JE STOP
	CMP AH,3BH
	JE BSET
	CMP AH,3CH
	JE FSET
	CMP AH,4DH
	JE DRAW1
	CMP AH,4BH
	JE DRAW2
	CMP AH,48H
	JE DRAW3
	CMP AH,50H
	JE DRAW4
	JMP READY
BSET:	INC COLORB
	MOV AH,0BH
	MOV BL,COLORB
	MOV BH,0
	INT 10H
	JMP READY
FSET:	INC COLORF
	JMP READY
DRAW1:	INC CX
	CMP CX, RGTCOL
	JG SDR1
	JMP DISP
SDR1:	DEC CX
	JMP READY
DRAW2:	DEC CX
	CMP CX, LETCOL
	JL SDR2
	JMP DISP
SDR2:	INC CX
	JMP READY
DRAW3:  DEC DX
	CMP DX, TOPROW
	Jl SDR3
	JMP DISP
SDR3:	INC DX
	JMP READY
DRAW4:	INC DX
	CMP DX, BOTROW
	JG SDR4
	JMP DISP
SDR4:	DEC DX
	JMP READY
DISP:	MOV BL,COLORF
	MOV AH,0CH
	MOV AL,COLORF
	INT 10H
	JMP READY
STOP:	POP AX
	MOV AH,0
	INT 10H
	MOV AH,4CH
	INT 21H
CODE ENDS
END START