ACR3901T-W1 – Reference Manual
Version 1.02
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Page 50 of 100
7.1.4.
Rewrite Master Key Command
This command rewrites the master key to the reader. It is required to be encrypted by the old key
using the AES encryption algorithm.
Command Format
Offset
Field
Size
Value
Description
0
abData1
CommandCode
1
07h
Command Code of Rewrite
Master Key
1
Len (CommandLength)
1
20h
Number of extra bytes of data
2
Data
32
-
Combine the random number
(KeyRstRnd[0:15]) encrypted
by original Customer Master
Key + 16 byte of new
Customer Master Key
encrypted by the original
Customer Master Key
Response Format
Offset
Field
Size
Value
Description
0
abData2
ResponseCode
1
87h
Response Code of Rewrite
Master Key
1
Len (CommandLength)
1
01h
Number of extra bytes of data
2
Data
1
-
00h = Success
01h = Fail
Example:
Customer Master Key Reset Request