ACM1281U-C7
– Reference Manual
Version 1.02
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Notes:
1. The application should know all the keys being used. It is recommended to store all the
required keys to the non-volatile memory for security reasons. The contents of both volatile
and non-volatile memories are not readable by any application.
2. The content
of the volatile memory “Session Key 20h” will remain valid until the reader is
reset or powered-off. The session key is useful for storing any key value that is changing from
time to time. The session key is stored in the “Internal RAM”, while the non-volatile keys are
stored in “EEPROM” that is relatively slower than the “Internal RAM”.
3.
It is not recommended to use the “non-volatile key locations 00-1Fh” to store any “temporary
key” that will be changed frequently. The “non-volatile keys” are supposed to be used for
storing any “key value” that will not change frequently. If the ”key value” is supposed to be
changed from time to time, store the “key value” to the “volatile key location 20h” instead.
