SC23M42
7) Compare authentication data
Control
B7
Binary
Hex
0
B6
0
B5
1
B4
1
33H
B3
0
B2
0
B1
1
B0
1
Address
A7… A0
Address
00H… 03H
Data
D7… D0
Input data
Input data
Validate the appointed byte of PSC each time.
4. Password authentication
The SC23M42 is only readable without PSC authentication. The content of PSC cannot be read, if you try to
read PSC, you will get “ .
00”
The authentication steps are as follows:
--Write to one bit of the error counter (EC) which has not been written, and the EC address is“ ;
00”
--Input the first byte data of PSC code, and the address is“
01”
--Input the second byte data of PSC code, and the address is “
02”
-- Input the third byte data of PSC code, and the address is “
03”
--If pass the authentication, EC can be erased.
If the initial value of the error counter is “ , the error counter cannot be written, and also cannot go through
00”
the password authentication. After the PSC authentication, I/O port will change from “ to “ at the raising edge
1” 0”
of the second clock no matter pass the authentication or not. When RST changes from “ to“ I/O port returns
0” 1”
to “ . The flow chart is as follows:
1”
HANGZHOU SILAN MICROELECTRONICS CO.,LTD
Http: www.silan.com.cn
REV:1.0
2006.07.21
Page 8 of 11
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