USER MANUAL
STM 550X / EMSIX
–
ENOCEAN MULTI-SENSOR
© 2020 EnOcean | www.enocean.com F-710-017, V1.0
STM 550x / EMSIx User Manual | v1.0 | February 2020 | Page 27/79
4
Radio communication
STM 550x devices communicate using radio telegrams encoded according to the EnOcean
Equipment Profile (EEP) specification and the EnOcean Alliance Signal Telegram specification
on a radio link according to the EnOcean Alliance Radio Protocol (ERP).
STM 550 uses the ERP1 standard (ISO 14543-3-10) while STM 550U and STM 550J use the
ERP2 (ISO 14543-3-11) standard.
4.1
Radio Frame format
As described above, STM 550 uses ERP1 as radio link while STM 550U and STM 550J use
ERP2.
Note that EnOcean radio transceivers such as TCM 310 or TCM 515 will convert both ERP1
and ERP2 into the same EnOcean Serial Protocol (ESP3) format so that this difference is
normally not noticeable.
4.1.1
ERP1 frame format
The ERP1 radio frame format is shown in Figure 16 below.
RORG
DATA
SENDER EURID
STATUS
CRC
Figure 16
–
ERP1 Frame Format
The most relevant fields of the ERP1 frame are the following:
◼
RORG (containing the EEP or SIGNAL RORG)
◼
SENDER EURID (Device address of the sender)
◼
DATA (Telegram payload containing the EEP)
4.1.2
ERP2 frame format
The ERP2 radio frame format is shown in below.
LENGTH
HEADER
EXT_HEADER
SENDER EURID
DATA
CRC
Figure 17
–
ERP2 Frame Format
The most relevant fields of the ERP2 frame are the following:
◼
HEADER (including the EEP or SIGNAL RORG)
◼
SENDER EURID (Device address of the sender)
◼
DATA (Telegram payload containing the EEP)
