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Code: Select all

;bootsect.asm
[BITS 16]
[ORG 0x07C00]

jmp start
                
BOOTSEG  EQU 0x07c0                        
INITSEG  EQU 0x9000                
        
start:
      mov ax,BOOTSEG
      mov ds,ax
      mov ax,INITSEG
      mov es,ax
      mov cx,20
      sub si,si  
      sub di,di
      rep
      movsw        
      nop
      nop 
      jmp  INITSEG:go ;I find the go offset address is error
go:   mov        ax,cs
      mov        ds,ax
      mov        es,ax
      mov        ss,ax
      mov        sp,0xFF00

      nop
      nop
      call DispStr   
      jmp $
DispStr:
      mov ax,BootMessage  ;this BootMessage offset address is error,too
      mov bp,ax
      mov cx,16
      mov ax,01301h
      mov bx,000ch
      mov dl,0
      int 10h
      ret

BootMessage:db"Hello, OS world!"
        
times 510-($-$$) db 0
dw  0xaa55

Code: Select all

;bootsect.asm
[BITS 16]
[ORG 0x07C00]

start:
      mov ax, 0x0000
      mov ds, ax
      mov es, ax
      mov fs, ax
      mov gs, ax
      mov ss, ax
      mov sp, 0xFF00
      mov si, BootMessage

printloop:
	mov ah, 0x0E
	lodsb
	cmp al, byte 0x00
	je finprint
	int 0x10
	jmp printloop

finprint:
      cli
      hlt

BootMessage db "Hello, bootloader world!", 0x00
       
times 510-($-$$) db 0
dw  0xAA55