NXP Semiconductors
MF1S50YYX_V1
MIFARE Classic EV1 1K - Mainstream contactless smart card IC for fast and easy solution development
MF1S50yyX_V1 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2018. All rights reserved.
Product data sheet Rev. 3.2 — 23 May 2018
COMPANY PUBLIC 279232 16 / 36
10 UID Options and Handling
The MF1S50yyX/V1 product family offers two delivery options for the UID which is stored
in block 0 of sector 0.
• 7-byte UID
• 4-byte NUID (Non-Unique ID)
This section describes the MIFARE Classic MF1S50yyX/V1 operation when using one of
the 2 UID options with respect to card selection, authentication and personalization. See
also Ref. 6 for details on how to handle UIDs and NUIDs with MIFARE Classic products.
10.1 7-byte UID Operation
All MF1S500yXDyy products are featuring a 7-byte UID. This 7-byte UID is stored in
block 0 of sector 0 as shown in Figure 7. The behaviour during anti-collision, selection
and authentication can be configured during personalization for this UID variant.
10.1.1 Personalization Options
The 7-byte UID variants of the MF1S50yyX/V1 can be operated with four different
functionalities, denoted as UIDFn (UID Functionality n).
1. UIDF0: anti-collision and selection with the double size UID according to ISO/IEC
14443-3
2. UIDF1: anti-collision and selection with the double size UID according to ISO/IEC
14443-3 and optional usage of a selection process shortcut
3. UIDF2: anti-collision and selection with a single size random ID according to ISO/IEC
14443-3
4. UIDF3: anti-collision and selection with a single size NUID according to ISO/IEC
14443-3 where the NUID is calculated out of the 7-byte UID
The anti-collision and selection procedure and the implications on the authentication
process are detailed in Section 10.1.2 and Section 10.1.3.
The default configuration at delivery is option 1 which enables the ISO/IEC 14443-3
compliant anti-collision and selection. This configuration can be changed using the
‘Personalize UID Usage’ command. The execution of this command requires an
authentication to sector 0. Once this command has been issued and accepted by the
PICC, the configuration is automatically locked. A subsequently issued ‘Personalize UID
Usage’ command is not executed and a NAK is replied by the PICC.
Remark: As the configuration is changeable at delivery, it is strongly recommended to
send this command at personalization of the card to prevent unwanted changes in the
field. This should also be done if the default configuration is used.
Remark: The configuration becomes effective only after PICC unselect or PICC field
reset.
