这里我们简单介绍一下Stage2.asm这个程序。
整个程序代码如下：
1: ; Note: Here, we are executed like a normal COM program, but we are still in
this loader to set up 32 bit mode and basic exception
3: ; handling
4:
5: ; This loaded program will be our 32 bit kernal.
6:
do not have the limitation of 512 bytes here, so we can add anything we
8: ; want here!
9:
10: org 0x0 ; offset to 0, we will set segments later
11: bits 16 ; we are still in real mode
12:
13: ; we are loaded at linear address 0x10000
14:
15: jmp main
16:
17: ;*********************************
18: ; Prints a String
19: ; DS=>SI: 0 terminated string
20: ;*********************************
21:
22: Print:
23: lodsb
24: or al, al
25: jz PrintDone
26: mov ah, 0eh
int 10h
28: jmp Print
29: PrintDone:
30: ret
31:
32: ;********************************
33: ; Second Stage Loader Entry Point
34: ;********************************
35:
36: main:
37: cli
38: push cs
39: pop ds
40: ; xor ax, ax ; org 0x0500
41: ; mov ds, ax ; org 0x0500
42:
43: mov si, Msg
44: call Print
45:
46: cli
47: hlt
48:
49: ;********************************
section
51: ;********************************
52:
,13,10,0