Datasheet
NXP Semiconductors
MF0ICU2
MIFARE Ultralight C - Contactless ticket IC
MF0ICU2 All information provided in this document is subject to legal disclaimers. © NXP B.V. 2019. All rights reserved.
Product data sheet Rev. 3.3 — 30 July 2019
COMPANY PUBLIC 137633 11 / 36
Any write operation to the lock bytes 0 and 1, features anti-tearing support.
Remark: The configuration written in the lock bytes is valid upon the next REQA or
WUPA command.
7.5.3 Lock byte 2 and 3
To lock the pages of the MF0UL21 starting at page address 10h onwards, the lock bytes
2 and 3 located in page 28h (byte 0 and 1 as shown in Figure 7) are used. Those two
lock bytes cover the memory area of 96 data bytes in pages 10h (16d) to 27h (39d)
and the configuration area from page address 28h onwards. The granularity is 4 pages,
compared to a single page for the first 512 bits as shown in Figure 7. The functionality of
the bits inside the lock bytes 2 and 3 are shown in Table 7.
Remark: Set all bits marked with RFUI to 0, when writing to the lock bytes.
aaa-013580
BLOCK
LOC
KI
N
G
PAGES
16
-
27
L
O
CK
PAG
E
36 - 39
L
O
CK
PAG
E
32 - 35
L
O
CK
PAG
E
28 - 31
BLOCK
LOC
KI
N
G
PAGES
29
-
39
L
O
CK
PAG
E
24 - 27
L
O
CK
PAG
E
20 - 23
L
O
CK
PAG
E
16 - 19
BLOCK
LOC
KI
N
G
L
O
CKBI
T A
UT
H
1
B
LOCK
LOC
KI
N
G
LO
CKBI
T
K
EY
BLOCK
LOC
KI
N
G
L
O
CKBI
T A
UT
H
0
B
LOCK
LOC
KI
N
G
LO
CKBI
T C
N
T
L
O
CKBI
T A
UT
H
1
PAG
E
4
3
L
O
CKBI
T A
UT
H
0
PAG
E
4
2
LO
CKBI
T C
N
T
PAG
E
4
1
LO
CKBI
T
K
EY
P
AGE
44
-
47
MSB
6 5 4 3 2 1 bit 7 6 5 4 3
LSB MSB LSB
page 40 (28h) 10 2 3
0bit 7 0 12
Figure 7. Lock bytes 2 and 3
The default value of lock bytes 2 and 3 is 00 00h. The value of byte 3 on page 28h (see
Figure 7) is always BDh when read.
The contents of bytes 2 and 3 of page 28h are unaffected by the corresponding data
bytes of the WRITE (see Section 9.3) or COMPATIBILITY_WRITE (see Section 9.4)
command.
Table 7. Functionality of lock bits in lock byte 2 and 3
Lock Byte Bit Function Block Locking
in Lock Byte
Block Locking
in Bit
2 1 lock page 16-19 2 0
2 2 lock page 20-23 2 0
2 3 lock page 24-27 2 0
2 5 lock page 28-31 2 4
2 6 lock page 32-35 2 4
2 7 lock page 36-39 2 4
3 4 lock Counter 3 0
3 5 lock AUTH0 3 1
3 6 lock AUTH1 3 2
3 7 lock Key 3 3