MFRC531 datasheet(10/13 Pages) PHILIPS

10 / 13 page

Philips Semiconductors

Short From Specification Rev. 2.0 February 2002

ISO 14443 Reader IC

MF RC531

PUBLIC

4 MIFARE

® CLASSIC RELATED ITEMS

4.1 CRYPTO I: Card Authentication

For correct authentication of MIFARE

® Classic

products the fast CRYPTO 1 stream cipher is

available. The corresponding keys have to be

programmed into the secure non-volatile key

memory of the MF RC531.

Only two commands need to be sent by

application software to turn on CRYPTO 1

secured communication.

4.1.1 INITIATING CARD AUTHENTICATION

The correct key for the authentication has to be

selected from the secure internal non-volatile key

memory and loaded into the internal CRYPTO1

transmitted to the card.

After receiving the first message token from the

card, the µ-Controller has to check the

communication status flags. If communication so

far has been successful the second part of the

authentication procedure can be started.

4.1.2 SECOND PART OF CARD

AUTHENTICATION

Data to be transmitted to the card in this phase

are generated automatically by the internal

CRYPTO 1 unit inside the MF RC531. To request

this action the according command has to be

triggered.

The card will respond with the second message

token. Then the communication status flags have

to be checked by the µ-Controller. If

authentication has been successful further

communication with a MIFARE

® Classic card

continues CRYPTO 1 enciphered.

MFRC531 Datenblatt(PDF) 10 Page - NXP Semiconductors