RU_TOOL/A20.asm at main · CoderLambert/RU_TOOL · GitHub

1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
.model small
.586
public display_a20
extrn  first_screen:far,QUIT:far,clear_screen:far,ib_free:far
.data
kbc_satte_present db 'kbc present now ','$'
kbc_satte_not_present db 'kbc not present now ','$'
  msg_enable_fast_ga20  db 'enable  a20      ','$'
  msg_disable_fast_ga20 db 'disable  a20      ','$'
  msg_port     db'1.enable  a20       2.disable  a20','$'
  msg_kbc     db'3.enable  a20       4.disable  a20(keyboarf controler)','$'
  msg_enable_fast_kbc  db 'enable a20 by keboard          ','$'
  msg_disable_fast_kbc  db 'disable a20 by keboard          ','$'
  MESG_RETURN DB 'Return menu: ESC       Rewrite: Tab and Backspace ','$'
  .code

  display_a20:
   include MACRO_zifu.MAC
   call clear_screen

        mov BH,0
	    MOV DH,1    ;放入行号
	    MOV DL,3     ;放入列号
        mov AH,02h
	    INT 10H;

 msg msg_port

        mov bh,0
	    mov dh,23    ;放入行号
	    mov dl,1     ;放入列号
        mov ah,02h
	    int 10h;


	    msg  MESG_RETURN


		NO_INPUT_key:

		 push ax
         push bx
         push dx
         mov BH,0
	     MOV DH,3    ;放入行号
	     MOV DL,3     ;放入列号
         mov AH,02h	  ;display start point
	     INT 10H;
         pop dx
         pop bx
         pop ax
         	 MOV AH,11H
		 	 INT 16H      ;检测按键是有否按下，有则判断按键是否是ESC,否则继续刷新
             jz NO_INPUT_key
			 mov ah,0
			 int 16h

			 cmp ah,01h     ;若为Q 键则退到主界面
			 jz  first_screen
			 ; cmp  al,'1'
			 ; jz   enable_fast_ga20

			 cmp al,'1'
			 jz  enable_addr_bit_20
			 cmp al,'2'
			 jz  disable_addr_bit_20
			 jmp NO_INPUT_key


enable_addr_bit_20:
mov ah, 0DFh ; Data for output port to enable A20.
ed_00:
mov al, 0D1h
out 64h, al
ed_01:
 jcxz $+2
in al, 64h
cmp al, 0FFh

je kbc_not_present
call ib_free
mov al, ah
out 60h, al

msg msg_enable_fast_kbc
JMP NO_INPUT_key

kbc_not_present:

mov al, 02h
out 92h, al
cmp sp, sp ; ZF - Indicates Gate-A20 enabled.

msg msg_enable_fast_ga20
jmp NO_INPUT_key


disable_addr_bit_20 :
mov ah, 0DDh ; Data for output port to disable A20.
ed_2:
mov al, 0D1h
out 64h, al
ed_21:
 jcxz $+2
in al, 64h
cmp al, 0FFh

jz kbc_not_present1
call ib_free
mov al,ah
out 60h,al


msg msg_disable_fast_kbc

jmp NO_INPUT_key

kbc_not_present1:

mov al, 00h
out 92h, al
cmp sp, sp ; ZF - Indicates Gate-A20 disabled.
msg msg_disable_fast_ga20

JMP NO_INPUT_key

   END