User's Manual
THE
80286
INSTRUCTION
SET
Table
B-3.
Hexadecimal
Values
for
the
Access
Rights
Byte
Not
present, Present,
privilege =
privilege=
Descriptor Type
0
1
2 3 0
1 2 3
00
20 40
60
80
AO
CO
EO
Illegal
01
21
41
61
81
A1
C1
E1
Available Task State Segment
02 22 42 62
82
A2
C2
E2
Local Descriptor Table Segment
03 23
43
63 83 A3
C3
E3
Busy Task State Segment
04 24 44 64
84
A4
C4
E4
Call Gate
05 25 45 65 85
A5
C5
E5
Task Gate
06
26 46 66 86
A6
C6
E6
Interrupt Gate
07 27 47 67
87
A7
C7
E7
Trap Gate
08 28
48
68 88
A8
C8
E8
Illegal
09
29 49 69 89
A9
C9
E9
Illegal
OA
2A 4A 6A 8A AA CA
EA
Illegal
OB
2B 4B 6B 8B AB
CB EB Illegal
OC
2C
4C
6C
8C
AC
CC
EC
Illegal
00
20
40
60
80
AD CD
ED
Illegal
OE
2E
4E
6E
8E
AE CE
EE
Illegal
OF
2F 4F 6F 8F AF CF
EF
Illegal
10 30 50 70 90
BO
DO
FO
Expand-up, read only, ignored Data Segment
11
31
51
71
91
B1
01
F1
Expand-up, read only, accessed Data Segment
12 32 52 72 92 B2
02
F2
Expand-up, writable, ignored Data Segment
13 33 53 73 93 B3
03
F3
Expand-up, writable, accessed Data Segment
14 34 54 74
94
B4
04
F4
Expand-down, read only, ignored Data Segment
15 35 55 75 95
B5
05
F5
Expand-down, read only, accessed Data Segment
16 36 56
76
96
B6
06
F6
Expand-down, writable, ignored Data Segment
17
37
57
77
97 B7
07
F7
Expand-down, writable, accessed Data Segment
18 38 58
78 98 B8
08
F8
Non-conform, no read, ignored Code Segment
19
39 59 79 99 B9
09
F9
Non-conform, no read, accessed Code Segment
1A
3A
5A 7A 9A BA
DA
FA Non-conform, readable, ignored Code Segment
1B
3B
5B 7B 9B
BB
DB
FB Non-conform, readable, accessed Code Segment
1C 3C
5C
7C 9C
BC DC
FC
Conforming,
no
read, ignored Code Segment
10
3D
50
70
90
BD
DO
FD
Conforming,
no
read, accessed Code Segment
1E
3E
5E
7E
9E
BE
DE
FE
Conforming, readable, ignored Code Segment
1F
3F 5F 7F 9F BF
OF
FF
Conforming, readable, accessed Code Segment
8-14