USER MANUAL
STM 550 / EMSI
–
ENOCEAN MULTISENSOR FOR IOT APPLICATIONS
© 2020 EnOcean | www.enocean.com F-710-017, V1.0
STM 550 / EMSI User Manual | v1.3 | September 2020 | Page 42/97
8
NFC interface
STM 550 implements am NFC configuration interface that can be used to access (read and
write) the STM 550 configuration memory and thereby configure the device as described in
the following chapters.
NFC communication distance is for security reasons set to require direct contact between
the NFC reader and the STM 550 device.
Note that STM 550 temporarily stops operation while the NFC reader is actively connected
to the NFC interface of STM 550. STM 550 operation will automatically resume operation
once the NFC reader has been disconnected.
Once the NFC reader has been disconnected, STM 550 will implement basic parameter vali-
dation (parameters within permitted boundaries) before accepting updated NFC parame-
ters.
Should an updated parameter be out of bounds then all updated parameters will be re-
jected and the previous configuration will be retained. Otherwise the updated NFC parame-
ters will be processed and the product parameters will be adapted accordingly.
8.1
NFC interface parameters
The NFC interface of STM 550 uses NFC Forum Type 2 Tag functionality as specified in the
ISO/IEC 14443 Part 2 and 3 standards. It is implemented using an NXP NT3H2111 Mifare
Ultralight tag.
8.2
NFC access protection
Protected data access is only possible after unlocking the configuration memory with the
correct 32 bit PIN code. By default, the protected area is locked and the default pin code for
unlocking access is
0x0000E500
.
The default pin code shall be changed to a user-defined value as part of the installation
process. This can be done by unlocking the NFC interface with the old PIN code and then
writing the new PIN code to page
0x4B.