SRTAG2KL memory management
SRTAG2KL
3.3
Access right life time
The access right life time is validated while the NDEF file is selected or until the end of the
RF session. Once the read or write access right is granted, the host can send one or more
ReadBinary or UpdateBinary commands.
At the end of a session or when the host selects another file, the read and write access
rights are initialized.
3.4
Note:
NDEF file passwords
The NDEF file passwords protect the read or write access from an RF interface from/to an
NDEF file.
Two NDEF file passwords are available for each NDEF file:
• Read password
• Write password
The length of a password is 128 bits (16 bytes).
The delivery state for all passwords = 0x00000000000000000000000000000000.
3.5
Read/Write counter
A 20 bits counter can track the read or write events on the NDEF file.
It benefits from an anti-tearing mechanism, that ensures the consistency of the counter,
even if there has been an electrical problem during its increment.
The value of the Read/Write counter can be checked by any application, by reading suitable
bytes in System file (see Section 3.1.4).
If enabled, the Read/Write counter will be incremented on first event (exclusively Read or
Write) which is performed on the NDEF File, inside an RF session (an RF session is entered
when SRTAG2KL receives a valid "Select Application" command).
The counter is reset when it is disabled.
Apart from these procedures, there is no way to act on the value of this counter.
The Read/Write counter can be configured through a specific byte in System file (see
Section 3.1.4).
This configuration byte allows to:
• Enable or disable this counter
• Define if the counter must be incremented on a read or write sequence
• Definitively lock this configuration byte
Warning: Once this configuration byte is locked, it cannot be changed
anymore: the counter will behave accordingly.
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