Pilz PITreader - 5.6 Coding

Function description
Operating Manual PITreader, PITreader Firmware V1.5.x
1004806-EN-08
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5.6 Coding
Through the coding process, PITreader devices can be restricted to recognising certain
transponder keys coded with the same identifier.
There are two different codings:
} Basic coding [ 25]
} OEM coding [ 25]
The identifiers for both codings can be stored on a PITreader. Only the identifier for one of
the codings can be stored on the transponder key.
The effect of the codings is the same, but they differ in the way the identifiers are changed
and deleted on the PITreader and the way in which the transponder key is taught in.
Identifiers are safely stored within the device in a hardware security block. When transpon-
der keys are taught in they are given a tamper-proof, cryptographic signature, which se-
curely protects your system from manipulation and unknown transponder keys.
Teaching in a coded transponder key
If additional transponder keys are to be added to a PITreader that uses coding, the new
transponder keys must be taught in on an appropriately coded PITreader before they are
first used.
INFORMATION
If an (as yet) uncoded transponder key is inserted into the read area of the
PITreader or the PITreader and transponder key are coded with different
identifiers, the transponder key will not be read and the PITreader will indic-
ate an error (LED flashes red). In this case the data from the transponder
key will not be readable via the Modbus/TCP connection and there can be
no (external) authentication of the transponder key.
Protection against unauthorised reading of a coded transponder key
Both coded and uncoded transponder keys will work on an uncoded PITreader; i.e. the data
from a coded transponder key can also be read by an uncoded PITreader. To prevent this,
a coded transponder key can also be configured so that reading is limited to identically
coded PITreader devices (see Limit transponder key to identically coded
PITreader [ 40]).
Monitoring the coding using a check sum
For both basic and OEM coding, a check sum can be used to monitor whether the coding in
the PITreader has been changed.
Properties of the check sum:
} Data length of the check sum: 16 Byte
} If coding has not been set, then the check sum is 0.
} If coding has been set, then a check sum is calculated. The check sum is recalculated
each time the coding is changed; i.e. each time the coding changes, the check sum
changes.