p5df072ev2 NXP Semiconductors, p5df072ev2 Datasheet - Page 14

• Manufacturer Part Number: p5df072ev2
• Description: Mifare Sam Av1
• Manufacturer: NXP Semiconductors

NXP Semiconductors
P5DF072EV2/T0PD4090_SDS_31
Product short data sheet
PUBLIC
7.5.11 DESFire related commands
ISO14443-4_Exchange
Exchange bytes according to ISO/IEC 14443-4 T=CL protocol.
ISO14443-4_PresenceCheck
Check if an activated card is still in the field.
ISO14443-4_Deselect
Deselect an activated card. The CID is freed by this command. If the deselect fails, the
CID will not be freed and cannot be used for activating another card. This behavior might
be overridden by setting a flag in the P1 byte.
ISO14443-4_FreeCID
Free one, more, or all currently assigned CIDs. This command might be necessary if
several deselect commands failed and the CIDs were not forced to be freed but the card is
deactivated or no longer available in the field.
DESFire_AuthenticatePICC
In this procedure both the PICC as well as the SAM device, show in an encrypted way that
they posses the same secret which especially means the same key. This procedure not
only confirms that both entities are permitted to do operations on each other but also
creates a session key which can be used to keep the communication path secure. As the
name ‘session key’ implicitly indicates, each time a new authentication procedure is
successfully completed a new key for further cryptographic operations is obtained.
DESFire_ChangeKeyPICC
This command generates the cryptogram that has to be sent to the PICC in order to
change any key stored in the PICC. Both the current and the new key need to be stored in
the KST to execute this command. Be aware that this command may have some
limitations, see
DESFire_WriteX
Write data encrypted or MACed on a DESFire PICC. This command shall be used to issue
the ChangeKeySettings, WriteData, Credit, Debit, LimitedCredit or WriteRecord
command. It takes the data to be sent to the DESFire and applies the encryption or
MACing mechanism starting from an indicated index. The user is responsible for providing
the correct command frame including the command code, the parameter bytes and the
plain data as specified for the DESFire PICC. The indication from which position on the
crypto mechanism shall be applied will normally be the first data byte of the command
frame. The SAM will automatically adapt the amount of bytes to send to the PICC after
encryption of data or adding the MAC, respectively.
DESFire_ReadX
Read encrypted or MACed data from the DESFire PICC. This command shall be used to
issue the ReadData, GetValue, or ReadRecords command. It takes the data to be sent to
the DESFire and applies the decryption and MAC verification mechanism to the received
data. Afterwards the SAM returns the decrypted or verified plain data. The user is
responsible for providing the correct command frame including the command code and
the parameter bytes as specified for the DESFire PICC.
Ref.
All information provided in this document is subject to legal disclaimers.
3.
Rev. 3.1 — 14 June 2010
189731
P5DF072EV2/T0PD4090
MIFARE SAM AV1
© NXP B.V. 2010. All rights reserved.
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