67
Three control bits exists in the access control byte by positive or
negative form,
determines access rights to the block (such as impairment operation must verify KEY
A, for value-added operations must verify KEY B, etc). the position of three control
bits in the access control byte as follows (byte 9 is
spare byte, default is 0x69):
keyA
control bits
key B
bit
7
6
5
4
3
2
1
0
Byte 6
C23_
b
C22_
b
C21_
b
C20_
b
C13_
b
C12_
b
C11_
b
C10_
b
Byte 7
C13
C12
C11
C10
C33_
b
C32_
b
C31_
b
C30_
b
Byte 8
C33
C32
C31
C30
C23
C22
C21
C20
Byte 9
(remark:_b means negation ,For example: if c11 is 1, c11_b is 0; c11 is
0, c11_b is 1 )
1. Control block(block 3)the acess control of block 3 is different from the data
block(blocks 0,1,2), its access control are as follows:
key A
Control bit
Key B
C13
C23
C33
Read
Write
Read
Write
Read
Write
0
0
0
Never
KeyA|B
KeyA|B
Never
KeyA|B
KeyA|B
0
1
0
Never
Never
KeyA|B
Never
KeyA|B
Never
1
0
0
Never
KeyB
KeyA|B
Never
Never
KeyB
1
1
0
Never
Never
KeyA|B
Never
Never
Never
0
0
1
Never
KeyA|B
KeyA|B
KeyA|B
KeyA|B
KeyA|B
0
1
1
Never
KeyB
KeyA|B
KeyB
Never
KeyB
1
0
1
Never
Never
KeyA|B
KeyB
Never
Never
1
1
1
Never
Never
KeyA|B
Never
Never
Never
(KeyA|B means key A or key B,
Never means
that can not be realized under any
conditions)
For example: the block 3, access control bits is C13 C23 C33 = 100, means:
Password A: unreadable, verify KEYB correct, may write (change).
Access control: authentication KEYA or KEYB correctly, readable but can not write
Password B: unreadable, verify KEYB correctly, can write.)
A0 A1 A2 A3 A4 A5
FF 07 80 69
B0 B1 B2 B3 B4 B5