Capture effect optional Preheader allows it; Rx may use it 6 HBES RF Data Link Layer 6.1 HBES RF Data Link Layer for all HBES RF devices 6.1.1 Differences to existing bidirectional HBE
Terms and definitions
For the purposes of this document, the terms and definitions given in EN 50090-1:2011 and the following apply
RF channel hopping action to change the RF channel during or after transmitting a frame
The budget link of a device is defined as the difference in decibels (dB) between the maximum radiated power and the radiated sensitivity A higher budget link indicates an improved radio range, enhancing the device's performance.
Abbreviations
F1 F1 RF channel with a preamble of 15 ms in the transmitted Frame
F1r F1 RF channel with a preamble of 4,8 ms in the transmitted Frame
F1sh F1 RF channel with a preamble of 1ms in the transmitted Frame
Fx One of F1, F2 or F3 RF channels
GFSK Gaussian Frequency Shift Keying
NPRM Non-Permanent Reception Mode
RSSI Received Signal Strength Indication
Sx One of S1 or S2 RF channels
As described in the scope, this European standard defines the RF Physical Layer requirements for:
For HBES certification in Europe, the products shall be in compliance with at least one of the following clauses
System Physical Layer Data Link Layer
HBES RF Ready 5.1 6.1 and 6.2 HBES RF Multi 5.2 6.1 and 6.3
Physical Layer for HBES RF Ready
Signalling for HBES RF Ready
Table 2 — General requirements for Physical Layer Type HBES RF Ready
Characteristic Value or applicable standard
Tx centre frequency fc = 868,300 MHz
Max Tx frequency tolerance ± 25 ppm a
FSK deviation fDEV = ± 48 kHz to ± 80 kHz typically 60 kHz
Tx chip rate 32 768 chips per second
Maximum Tx chip rate tolerance ± 1,5 %
Maximum Tx jitter per transition ± 5 às
Rx blocking performance according to ETSI EN 300 220-1, category 2 receivers b
Rx centre frequency fc = 868,300 MHz
Rx frequency tolerance ± 25 ppm HBES Tx to HBES Rx a, b ± 60 ppm Metering Tx to HBES Rx a, b Minimal Rx chip rate tolerance ±2,0 % b
The typical Rx radiated sensitivity is -95 dBm, with a minimal sensitivity of -80 dBm The device operates effectively within a temperature range of 0°C to 45°C This frequency tolerance accounts for variations due to temperature changes and crystal aging The specified Bit Error Rate (BER) of 10^-4 is achieved in the optimal antenna direction Additionally, the HBES Physical Layer parameters must be maintained throughout the entire temperature range specified by the manufacturer, which may extend from -10°C to 70°C for outdoor applications.
A link budget of 100 dB is recommended.
Telegram structure for RF Ready
Table 3 — HBES Ready systems Telegrams definition
In Manchester encoding, a chip "0" represents the frequency \( fLO \) (calculated as \( fC - fDEV \)), while a chip "1" corresponds to the frequency \( fHI \) (calculated as \( fC + fDEV \)) A bit "0" is encoded as a transition from \( fHI \) to \( fLO \), indicated by the chip sequence "10", whereas a bit "1" is represented by a transition from \( fLO \) to \( fHI \), shown by the chip sequence "01" The preheader includes a Preamble.
Manchester violation, Sync word see below
Preamble 79x chip sequence "01" sent by Tx learning sequence for Rx, number of preamble chips is not checked by Rx (~4.8 ms) Manchester violation chip sequence "000111" necessary for capture effect
"011010010110" useful for synchronization on chip rate Postamble 2 chips to 8 chips software reasons, mandatory for all Tx, number of postamble not checked by Rx
Capture effect optional Preheader allows it; Rx may use it
Medium access RF Ready
Medium access control shall serve for prevention of collisions on the RF medium For two reasons medium access cannot be completely controlled on RF
1) Unidirectional senders access the medium at non-predictable times
2) Non HBES RF devices access the medium at non-predictable times
Bidirectional devices must detect if the communication medium is available before transmitting The inter-frame time refers to the duration a bidirectional device waits for a clear medium, independent of any previous frame addressing If a preamble is not detected during this inter-frame time, the device is permitted to begin transmission.
When a Frame is received during a request to send, the interFrame time begins only after the complete reception of the Frame, which occurs after the last CRC is received Similarly, if a send request is received while the Physical Layer is transmitting, the interFrame time starts once the last CRC is transmitted.
NOTE RF supports no collision avoidance; therefore the transmission priorities are not coded in the Frame
Type of frame InterFrame time
[Trd] Total medium access Time
REPEATED Ready frame 5 ms 0 ms ≤ Trd < 10 ms 5 ms ≤ Tma < 15 ms
15 ms 0 ms ≤ Trd < 15 ms 15 ms ≤ Tma < 30 ms
150 ms 0 ms ≤ Trd < 10 ms 150 ms ≤ Tma < 160 ms
The assumed typical ‘blind time’ for devices is 1 ms
The step for the random time shall be 1 ms.
Physical Layer for HBES RF Multi
General requirements (HBES RF Multi)
The RF channels used in the HBES RF Multi shall be composed of the following 3 + 2 RF channels
Table 5 – RF channels of the HBES RF Multi Physical Layer
RF channel name Abbreviation signalling speed kbps encoding preamble length ms
Primary fast RF channel F1 16,384 Manchester 15
Second fast RF channel F2 16,384 Manchester 15
Third fast RF channel F3 16,384 Manchester 15
Primary slow RF channel S1 8,192 Manchester 500
Second slow RF channel S2 8,192 Manchester 500
The RF channels shall be divided in two categories
1) The first category shall contain RF channels for “fast” RF Telegrams The fast Telegrams shall be composed of a short 15 ms wake-up at 16,384 kbps signalling speed
2) The second category contains RF channels for “slow” RF Telegrams The slow Telegrams are composed of a long 500 ms wake-up at 8,192 kbps signalling speed
The two categories of RF channels define explicitly two application domains
EXAMPLE 1 Non-permanent receivers: smoke sensors, heating control
EXAMPLE 2 Permanent receivers: all devices concerning human interaction
The initial three Fast RF channels are designed for fast permanent and non-permanent receivers, while the final two channels cater to slow non-permanent Rx devices The reception capability of the receiver influences the length of the preamble.
Devices from both categories can coexist independently without link or with links done by specific mains powered products receiving all the 5 RF channels
Fast Telegrams are Telegrams transmitted on any of the Fast RF channels; slow Telegrams are Telegrams transmitted on a Slow RF channel
NPRM devices that utilize slow Telegrams are designed to receive RF Telegrams with extended wake-up periods, allowing them to remain in low power mode for the majority of the time This design enables periodic activation for receiving long preambles It is recommended that battery-powered devices primarily utilize RF channels S1 and S2, which operate at lower data rates.
PRM devices supporting the Fast RF channels shall be in permanent scanning and receiving mode
NPRM devices that utilize Fast RF channels are required to scan each RF channel every 15 milliseconds, allocating 1 millisecond for hopping and another 1 millisecond for scanning Upon detecting a preamble, the device will listen to the Frame; otherwise, it will proceed to the next RF channel.
A receiver on only one RF channel without scanning any other is not permitted
The first RF channel in the Fast RF system is designated for RF HBES Ready devices, while the two additional Fast RF channels serve as escape options when the primary RF channel is occupied.
The two Slow RF channels consist of S1, designated for slow products, and an escape RF channel that activates when the primary RF channel is busy.
Devices will mainly use F1, F2, F3 or S1, S2: 5 RF channels will only in very seldomly be supported in applications.
Physical Layer type RF Multi
5.2.2.1 HBES RF1 channel definitions for RF channels F1, F2 and F3
Table 6 – RF channel definitions for RF1 channels F1, F2 and F3
Tx centre frequency Channel F1 868,300 MHz HBES Tx to HBES Rx b
Metering Tx to HBES RF Multi c
TX radiated power Typical: 0 dBm
Min: -3 dBm Max: +14 dBm Deviation ± 48 kHz to ± 80 kHz Typical : 60 kHz
Tx max duty cycle 1 % for F1
For F3 only, Duty Cycle is 100 % up to a maximum radiated power of 5 mW and restricted to 1 % from 5 mW to 25 mW
Tx chip rate 32 768 chips per second
Maximum Tx chip rate tolerance ±1,5 %
Maximum Tx jitter per transition ±5 às
Radiated test d BER : 10 -4 Minimal Rx chip rate tolerance ± 2 %
Preamble length 247x chip sequence “01” ~15 ms, number of preamble chips is not checked by Rx Receiver blocking performance Minimum category 2 Category 2 according ETSI EN 300 220 (all parts)
The minimal operating temperature range for the device is from 0°C to 45°C, with an optional RF channel F3 that may not be supported by the hardware Frequency tolerance accounts for temperature variations and crystal aging, and frequency error correction may be necessary for Tx metering specific to HBES Rx products, applicable only to RF channel F1 The device operates at a Bit Error Rate (BER) of 10^-4 when positioned in the optimal antenna direction Additionally, the HBES Physical Layer parameters must be maintained across the entire temperature range specified by the manufacturer, such as -10°C to +70°C for outdoor applications.
5.2.2.2 HBES RF1 channel definitions for RF channels S1 and S2
Table 7 — RF channel definitions for RF1 Multi channels S1 and S2
Tx centre frequency Channel S1 869,850 MHz Tx: ±25 ppm a
Tx radiated power Typical: 0 dBm
Min: -3 dBm Max: +14 dBm Deviation ±20 kHz to ±65 kHz The usage of frequency error correction may be needed to guarantee good receiver performances
Tx max duty cycle 100 % for S1
For S1 only, Duty Cycle is 100 % up to a maximum radiated power of 5 mW and restricted to 1 % from 5 mW to 25 mW
Tx chip rate 16 384 chips per second
Maximum Tx chip rate tolerance Tx: ±1,5 %
Maximum Tx jitter per transition ±5 às
Radiated test b BER = 10 -4 Minimal Rx chip rate tolerance ± 2 %
The preamble length is 4111 chips with a sequence of "01," lasting approximately 500 ms, while the receiver does not check the number of preamble chips The receiver's blocking performance meets the minimum requirements of Category 2 as specified by ETSI EN 300 220 The minimal operating range is from 0°C to 45°C, accounting for frequency tolerances due to temperature variations and crystal aging This is applicable at a Bit Error Rate (BER) of \(10^{-4}\) in the optimal antenna direction Additionally, the HBES Physical Layer parameters must be satisfied across the entire temperature range declared by the manufacturer, such as -10°C to +70°C for outdoor applications.
Telegram structure for HBES RF Multi systems
Table 8 – HBES RF Multi Telegrams definition
In Manchester data encoding, a chip "0" represents the frequency \( fLO \) (calculated as \( fC - fDEV \)), while a chip "1" signifies the frequency \( fHI \) (calculated as \( fC + fDEV \)) A bit "0" is encoded as a transition from \( fHI \) to \( fLO \) in the chip sequence "10", whereas a bit "1" is represented by a transition from \( fLO \) to \( fHI \) in the chip sequence "01" The preheader includes a Preamble.
Manchester violation, Sync word see below
Preamble See above Depends on which RF channel is used
Manchester violation chip sequence “000111” necessary for capture effect
“011010010110” useful for synchronization on chip rate Postamble 2 chips to 8 chips software reasons, mandatory for all Tx, number of postamble not checked by Rx
(Only applicable if no Fast Ack is used, refer to 6.3.4.3.) Capture effect optional Preheader allows it; Rx may use it
6 HBES RF Data Link Layer
HBES RF Data Link Layer for all HBES RF devices
Differences to existing (bidirectional) HBES EN 50090 protocol
The Extended Group Address in an HBES RF Frame consists of a standard HBES Group Address (2 octets) combined with the sender's HBES Serial Number or RF Domain Address (6 octets) Each group addressed HBES RF Frame must include this Extended Group Address.
Any received Frame shall be taken in account by the receiver only if the Extended Group Address of the sender is known by the receiver
NOTE According to the RF Frame, these 8 octets are not transmitted consecutively
The HBES RF Frame must include the HBES Serial Number or the RF Domain Address of the sender, as specified in Table 9 The sender is required to specify the utilized value—either the HBES Serial Number or the RF Domain Address—by indicating it in the Address Extension Type (AET) field, also detailed in Table 9.
Table 9 — Use of HBES Serial Number or RF Domain Address communication mode
The HBES serial number identifies the sender, while the RF domain address specifies the communication type In a point-to-system connectionless setup, broadcasting is enabled, whereas in a point-to-domain configuration, broadcasting is not supported For point-to-multipoint connections, multicast is allowed, and point-to-point connections are connectionless but do not support broadcasting Conversely, point-to-point connection-oriented setups do allow for broadcasting.
Address Extension Type (drExtensionType) (AET) 0 1 a It may depend on the used configuration mode whether the HBES RF device uses the HBES serial number or RF Domain Address
In any Frame in system broadcast communication mode the Destination Address shall be 0000h and the Address Type shall be “group”
6.1.1.2 Predefined Extended Group Addresses for transmit-only devices
Transmit-only devices must utilize Extended Group Addresses, as they are designed to send data with only one Group Address per Datapoint Consequently, all addresses can and should be pre-configured at the factory.
For unidirectional sensors, each datapoint is assigned a unique Group Address, starting with Datapoint 1 at Group Address 0001h, Datapoint 2 at 0002h, and continuing sequentially for Datapoint N at Group Address N This results in Extended Group Addresses on the bus, formatted as (HBES Serial Number of sensor, 0001h), (HBES Serial Number of sensor, 0002h), and (HBES Serial Number of sensor, N) It is essential that these Group Addresses remain unique for each sender.
All devices shall have the default Individual Address (05FFh)
6.1.1.3 Pre-defined Extended Group Addresses for bidirectional devices
In a 1-to-n relationship, groups are formed with one sender and multiple receivers When multiple senders manage a group of actuators, each actuator must respond to the sending addresses of all the senders.
The RF Domain Address shall be a 6 octet number It shall be guaranteed during the Configuration procedures that the RF Domain Address is a unique number
The RF Domain Address must be included in the RF Frame as specified in Table 9, indicated by a value of 1 in the AddrExtensionType field within the second block of the RF Frame.
The receiver shall discard the RF Frame if the field AddrExtensionType does not match with the used communication mode as given in Table 9
In any Frame in broadcast communication mode the Destination Address shall be 0000h and the Address Type shall be “group”
6.1.1.5 RF Broadcast and RF System Broadcast
Broadcasts can occur within an installation or as system broadcasts, with the AddrExtensionType field in the second block of the RF Frame indicating whether a broadcast is classified as a system broadcast.
- 0: system broadcast (shall not be restricted to the RF installation = domain; the Frame shall contain the HBES Serial Number of the sender)
- 1: broadcast (shall be restricted to the installation = domain; the Frame shall contain the
Data Link Layer Frame
This subclause specifies the Frame format of the HBES-RF system
The Frame format is based on the FT3 Data Link Layer (IEC 870-5) and includes a preamble at the Physical Layer, multiple data blocks each accompanied by 2 octets of CRC, and concludes with a postamble at the Physical Layer.
The first data block has a fixed length of 10 data octets The following blocks contain 16 data octets, except the last block, which may contain less than 16 octets (the remainder)
2 octets preamble data block 1 CRC data block 2 CRC … CRC postamble
Figure 1 — Overview of the Data Link Layer Frame 6.1.2.3 Bit and octet order
Data shall be transmitted most significant bit (msb) first
For data fields consisting of multiple octets (e.g HBES Serial Number/Domain Address and Device Addresses) the most significant octet (MSB) shall be transmitted first
6.1.2.4 First block octet 1 octet 2 octet 3 octet 4 octet 5 to octet 10 octet 11 and octet 12
Length C Esc RF-info SN/DoA CRC
7 6 5 4 3 2 1 0 res er ved rec eiv ed s ignal stre ng th bat ter y s tat e uni dir
Figure 2 — Structure of the first block
Description: According to IEC870-5: total number of user octets counted from the C-field (excluding the
CRCs) FFh value is reserved for future use.” See EN 50090-4-2
Description: According to IEC870-5 HBES only uses SEND/NO REPLY (C = 44h)
Description: This field shall have the fixed value FFh
Description: This bit is reserved for HBES system and shall be set to 0
Description: This bit shall be set to 0 by the sender
Description: These bits shall be set to 00b by the sender
Description: This field shall contain the received signal strength indication
This field shall be filled in by the Retransmitter with the lowest received signal strength; other senders shall always fill in the value 00h for this field
The Retransmitter shall not change the value if it cannot measure the signal strength Encoding: 00b: void (no measurement)
Description: This field shall contain the battery state of the sender of the Frame
Encoding: 0: Frame sent by bidirectional device
1: Frame sent by unidirectional device
Description: HBES Serial Number or Domain Address of the sender
The field AddrExtensionType in the LPCI in the second block shall indicate whether this field contains the HBES Serial Number or the Domain Address
Description: CRC according to IEC870-5-1
Encoding: For information: The CRC according to FT3 of IEC 870-5-1 uses
2 16 +2 13 +2 12 +2 11 +2 10 +2 8 +2 6 +2 5 +2 2 +2 0 as a generator polynomial It starts with zero and treats the data msb first The CRC result is complemented The MSB of the 16-Bit CRC is transmitted first
EXAMPLE 3 The sequence 01 02 03 04 05 06 07 08 has the CRC FCBCh
6.1.2.5 Second block for Standard Telegrams octet 1 octet 2 octet 3 octet 4 octet 5 octet 6 octet 7
HBES Ctrl Source Address Destination Address LPCI
The article discusses the structure and sequence of data packets, specifically focusing on the arrangement of octets and the importance of error-checking mechanisms like CRC It highlights the sequence numbers associated with each octet, from octet 8 to octet n, and extends to octets n+1 and n+2, ensuring data integrity throughout the transmission process.
AP CI AP CI AP CI /Da ta AP CI /Da ta AP CI /Da ta AP CI /Da ta AP CI /Da ta AP CI /Da ta
Figure 3 — Structure of the second block for Standard Telegrams
Description: The Frame format field is described in 6.1.3
Description: The Extended Frame Format field shall specify the format of the Frame
Other values are reserved (see EN 50090-4-2)
Description: The Source Address shall contain the Individual Address of the device that initiates the transmission of the Frame
Encoding: See EN 50090-4-2, Clause “Individual Address”
Description: This shall be the Destination Address of the Frame and shall be an Individual Address or a Group
Encoding: See EN 50090-4-2 for the format of the Individual Address and the Group Address
Description: This field shall specify whether the Destination Address is an Individual Address, a Group Address or the broadcast address
Encoding: For the Standard Frame, the encoding shall be as follows:
Description Specifies the maximum number of repetitions allowed for one Frame
• Data Link Layer Frame Number (LFN)
Description Sequence counter to discriminate successive Frames
Description: For the Standard Frame, the AET shall be used as follows:
Encoding: 0: The field SN/DoA in the first block shall be interpreted as the HBES Serial Number of the sender
1: The field SN/DoA in the first block shall be interpreted as the RF Domain Address
Description: The TPCI field shall contain the Transport Layer service indication
00b: unnumbered data 01b: numbered data 10b: unnumbered control 11b: numbered control
Description: This field shall contain the Sequence Number of the Frame
Description: The APCI field shall contain the Application Layer service indication
This block can contain up to 8 data octets, with a maximum block length of 16 octets Subsequent blocks will each consist of 16 octets, except for the last block, which may contain fewer than 16 data octets.
Use of the HBES Ctrl Field
Table 10 — HBES CTRL field values HBES Ctrl bit Frame Type
1 0 0 0 e e e e RF Multi asynchronous Data Frames L_Data
1 0 0 1 e e e e RF Multi asynchronous Data Frames L_Data with
1 0 1 0 0 0 0 0 RF Multi Repeater Acknowledge Frame
1 1 1 1 1 1 1 1 Escape value for future HBES Ctrl Extensions (2 Octet
HBES Ctrl FFxx) eeee = EFF field, see EN 50090-4-2 r = reserved Reserved bits are reserved for the HBES system
Reserved or unknown coding of HBES Ctrl shall not be used by the transmitter and shall be ignored by the receiver.
Data Link Layer protocol
The AddrExtensionType bit shall be a parameter of the Data Link Layer instance
In the transmission direction, the Data Link Layer instance must assess the AddrExtensionType and appropriately populate the SN/DoA field in block 1 of the transmitted Frame with either the device's own HBES Serial Number or the Domain Address.
In the reception direction, the Data Link Layer instance must utilize this bit to accurately interpret the SN/DoA field in block 1 of the received Frame, distinguishing it as either the HBES Serial Number or the Domain Address.
The Application Layer will set this Data Link Layer parameter, which will then be transmitted through the communication stack as input to the Data Link Layer by the other layers.
Please refer to EN 50090-4-2 for medium independent requirements for error and exception handling
In systems with Retransmitters, frame duplications may happen at the receivers when both the original sender and the Retransmitters send repeated signals To address this issue, Layer-2 implements a mechanism designed to prevent the processing of duplicated Telegrams at the receivers.
The Data Link Layer in each transmitter is responsible for inserting a 3-bit Link Layer Frame Number (LFN) into the LPCI of every transmitted Frame, as outlined in section 6.1.2.5 This LFN acts as a counter that increments with each Frame sent, resetting to zero after reaching 8 Frames.
In order to increase the probability to have no Frame lost, the Frame with the same LFN can be resent
The receiver shall discard subsequent Telegrams that contain the identical LFN from the same sender In case the LFN differs, the newly received LFN shall be stored
Each receiver must maintain a table to record the HBES Serial Number and the LFN of all received Telegrams, regardless of their origin The table should have a maximum length of 7, as the LFN ranges from 0 to 7 This practice prevents the accidental loss of Telegrams, even when only one device is sending them.
This mechanism ensures that repeated Telegrams originating from the same sender up to within the following 8 Telegrams are discarded.
Data Link Layer services
In addition to the general Data Link Layer protocol requirements specified in EN 50090-4-2, for the L_Data-service, the following shall apply
The L_Data service on HBES RF can function as either an unconfirmed or confirmed Telegram service When a local Data Link User prepares a Local Service Data Unit (LSDU) for one or more remote Data Link Layer users, it utilizes the L_Data.req service to transmit the LSDU to the local Data Link Layer This layer will accept the request and attempt to send the LSDU to the designated remote Data Link Layer Users, which may include an Individual Address, a Group Address, or a Broadcast Address Subsequently, the Local Data Link Layer will provide an L_Data.con primitive to the Local Data Link Layer User, indicating whether the data transfer was successful or encountered an error.
The Local Data Link Layer shall accept the L_Data.req service request The fields SN/DoA, AT and AET shall be filled in as follows
If the service parameter address_type denotes an Individual Address then
- the SN/DoA field in the Frame shall be filled with the RF Domain Address;
- the Address Extension Type (AET) shall be set to 1; this shall indicate that the SN/DoA field shall be interpreted as the RF Domain Address
- the Address Type field shall be set to 0; this shall denote that the Destination Address shall be interpreted as an Individual Address
If the address_type denotes a Group Address then a) if the Destination Address value equals the broadcast address 0000h then
1) the SN/DoA field in the Frame shall be filled with the RF Domain Address;
2) the Address Extension Type (AET) shall be set to 1; this shall indicate that the SN/DoA field shall be interpreted as the RF Domain Address
3) the Address Type field shall be set to 1; this shall denote that the Destination Address shall be interpreted as a Group Address b) if the Destination Address value does not equal the broadcast address 0000h but is a normal Group Address, then
4) the SN/DoA field in the Frame shall be filled with the HBES Serial Number of the sender or the RF Domain Address (depending on the way the HBES device was configured);
5) the Address Extension Type (AET) shall be set to 0 (this shall indicate that the SN/DoA field shall be interpreted as the HBES Serial Number of the sender) or 1 (this shall indicate that the SN/DoA field shall be interpreted as the RF Domain Address);
6) the Address Type field shall be set to 1; this shall denote that the Destination Address shall be interpreted as a Group Address
The service parameter Frame_format shall further indicate that the Frame shall be transmitted using a standard Telegram (see 6.1.2.5)
L_Data.req(address_type, destination_address, Frame_format, lsdu, octet_count, priority, source_address) address_type: This parameter shall be used to indicate whether the Destination
An address can be classified as either an Individual Address or a Group Address The parameter "destination_address" specifies the Destination Address for the Frame being transmitted, which can also be categorized as either an Individual Address or a Group Address.
The Frame_format parameter indicates an extended Frame format, while the lsdu parameter contains the user data to be transferred by Layer-2 The octet_count parameter specifies the length information of the requested Frame, and the priority parameter indicates the transmission priority for the requested Frame, which is set to "system."
“urgent”, “normal” or “low” source_address Individual Address of the device that requests the L_Data-service
The Local Data Link Layer shall increment the Data Link Layer Frame Number (LFN) by one compared to the previous transmitted L_Data-Frame
The Source Address shall be filled with the Individual Address of the Local Data Link Layer User.
HBES RF Data Link Layer for HBES RF Ready
Data Link Layer protocol
6.2.1.1 Data Link Layer for RF Ready
The general HBES RF Data Link Layer requirements as specified in 6.1 “HBES RF Data Link Layer for all HBES RF devices” shall apply
6.2.1.2 RF Repetition counter for end devices
The RF Repetition counter shall be set to 6 for end devices.
The Layer-2 of an RF Retransmitter
Filtering not implemented in HBES Ready
6.2.2.2.1 HBES Serial number based Retransmitter
Serial Number + LFN in History List?
Insert Serial Number and LFN in History list
Discard buffer No Yes Decrement RF Repeat
Data Link Layer Ph_Data.ind Ph_Data.req
NOTE This flowchart only describes the handling of received messages for repeating The handling of messages to the internal management of the Retransmitter is not shown
Figure 4 — HBES RF Ready flowchart of the Data Link Layer and Network Layer of the
6.2.2.2.2 HBES Domain Address based RF Retransmitter
DoA = own DoA ? Discard buffer no no yes yes
Ph_Data.ind Ph_Data.req
Retransmitter RF flag enabled disabled
Figure 5 — RF Domain Address based RF Retransmitter (basic flowchart)
The RF Retransmitter is designed to retransmit all RF Telegrams that have Extended Group Addresses, specifically those with AET = 0, provided there is no filter for SN.
- All Telegrams in point-to-system, connectionless communication mode (system broadcast)
- All Telegrams in point-to-multipoint, connectionless (multicast) communication mode using AET = 0
The RF Retransmitter will retransmit all RF Telegrams with AET = 1 when it has a configured RF Domain Address, provided that the RF DoA matches the device's own DoA.
- All Telegrams in point-to-multipoint, connectionless (multicast) communication mode using the
RF DoA of the RF Retransmitter This is normal group communication
- All Telegrams in point-to-domain, connectionless (broadcast) communication mode
- All Telegrams in point-to-point connectionless or – connection-oriented communication mode if the Destination Address does not equal the own Individual Address
This note pertains solely to the retransmission of Telegrams and does not address the handling of Telegrams directed to the RF device, including system broadcasts, point-to-point communications, or group communications.
HBES RF Data Link Layer specific to HBES RF Multi systems
Medium access RF Multi
HBES RF Multi devices medium access is based on a medium free check before transmission
Type of Frame InterFrame time
Total medium access time [Tma]
Ready Frame 15 ms 0 ms ≤Trd