ERP2

Owned by Matthias Kassner
11-Jul-2024
3 min read

EnOcean Radio Protocol version 2 (ERP2) is standardized as ISO14543-3-11 and used in all EnOcean products except the 868.3 MHz products used in EU. ERP2 uses Frequency Shift Keying (FSK) to encode individual bits which provides for a wide support in off-the-shelf transceiver solutions-

Telegram format

The ERP2 radio telegram format is shown below. Fields marked in dark grey are optional and might not be present.

image-20240626-065805.png
ERP2 Telegram Format

Telegram fields

The ERP2 telegram contains the following fields:

  • LENGTH
    This field specifies the total length of the ERP2 radio telegram 

  • HEADER
    This field specifies the EURID types and sizes, the R-ORG that is used (based on a selection of the most common EEP) and specifies if EXT_HEADER or EXT_TYPE is present

  • EXT_HEADER
    This is an optional field that specifies the repeater count and the length of OPTIONAL_DATA. It might be omitted by energy-constrained devices.

  • EXT_TYPE
    This is an optional field that is used to specify less common R-ORG which are not available within the HEADER field

  • SENDER EURID
    This field specifies the device address of the sender 

  • DESTINATION EURID
    This is an optional field that can be used to specify the device address of the intended recipient of a data telegram

  • DATA
    This field contains the telegram data 

  • OPTIONAL_DATA
    This is an optional field that can be used to transmit additional data that should be treated separately from the main telegram data. This field is not commonly used.

  • CRC
    This field is used to verify the integrity of the telegram

HEADER field

The HEADER field identifies the most commonly used EEP and the addressing mode (size of Source and Destination Address, Destination Address present yes / no). If the EEP that is used is not one of the most commonly used EEP, them the EXT_TYPE (Extended Telegram Type) field will be used to identify the EEP.

In addition, the HEADER field specifies if the EXT_HEADER (Extended Header) field is present.

image-20240627-122401.png
HEADER Field Structure

EXT_HEADER field

The EXT_HEADER field is mainly used to identify the repeater status of the telegram. In addition, it allows specifying the length of OPTIONAL DATA that is present in the telegram, but this feature is not commonly used.

EXT_TYPE field

The EXT_TYPE (Extended Telegram Type) field is used to identify less commonly used EEP which cannot be encoded in the HEADER field.

Â