ipl.asm

	CYLS EQU 10
	org	07c00h			; 告诉编译器程序加载到7c00处
	JMP	entry
	DB	0x90
	DB	"HARIBOTE"		
	DW	512				
	DB	1				
	DW	1				
	DB	2				
	DW	224				
	DW	2880			
	DB	0xf0			
	DW	9				
	DW	18				
	DW	2				
	DD	0				
	DD	2880			
	DB	0,0,0x29		
	DD	0xffffffff		
	DB	"HARIBOTEOS "	
	DB	"FAT12   "		
	TIMES 18 db 0	

entry:
	MOV	AX,0			
	MOV	SS,AX
	MOV	SP,07c00h
	MOV	DS,AX

	MOV	AX,00820h
	MOV	ES,AX
	MOV	CH,0 ; 柱面0
	MOV	DH,0 ; 磁头0
	MOV	CL,2 ; 扇区2	
readloop:
	MOV SI, 0
retry:
	MOV	AH,0x02	; 读入磁盘		
	MOV	AL, 1 ; 1个扇区
	MOV	BX, 0 
	MOV	DL,0x00 ; A驱动器			
	INT	0x13	; 调用
	JNC	next
	ADD	SI, 1
	CMP SI, 5
	JAE	error
	MOV	AH, 0x00
	MOV DL, 0x00
	INT	0x13 ;重置驱动器
	JMP	retry
next:
	MOV AX, ES
	ADD AX, 0x20
	MOV ES, AX
	ADD CL, 1
	CMP CL, 18
	JBE	readloop
	MOV CL, 1
	ADD DH, 1
	CMP DH, 2
	JB	readloop
	MOV DH, 0
	ADD CH, 1
	CMP CH, CYLS
	JB	readloop

	MOV [0x0ff0], CH
	JMP 0c400h
fin:
	HLT						
	JMP	fin				
error:
	MOV	SI,msg
putloop:
	MOV	AL,[SI]
	ADD	SI,1			
	CMP	AL,0
	JE	fin
	MOV	AH,0x0e			
	MOV	BX,15		
	INT	0x10	
	JMP	putloop
msg:
	DB	0x0a, 0x0a		
	DB	"load error"
	DB	0x0a			
	DB	0
	TIMES 510-($-$$) db 0  ; 填充剩下的空间，使生成的二进制代码恰好为512字节

	DB	0x55, 0xaa