Satellite signal distribution over a single coaxial cable - Second generation

This standard describes:  the system physical structure;  the system control signals, which implement a set of messages using DiSEqC physical layer but not the DiSEqC message structure;  the definition of identified configurations;  the management of the potential collisions in the control signals traffic. Figure 1 illustrates the physical system configuration considered in this standard. Several satellite signal demodulators can receive signals from any of the input signal banks (Bank 1, Bank 2,  Bank M, with M  256) of the LNB or the switch. The signals selected by the demodulators (or receivers) are transported via a single cable to these demodulators (Receiver 1, Receiver 2,  Receiver N, with N  32). To achieve these single cable distributions, the Single Cable Interface (SCIF, likely embedded in a LNB or a Switch) features some specific functions and characteristics.

Verteilen von Satellitensignalen über ein Koaxialkabel ‒ Zweite Generation

Distribution de signaux par satellite sur un seul câble coaxial - Deuxième génération

La présente Norme européenne décrit: ▪ la structure physique du système; ▪ les signaux de commande du système, qui mettent en oeuvre un ensemble de messages qui utilisent la couche physique DiSEqC, mais pas la structure de message DiSEqC; ▪ la définition des configurations identifiées; ▪ la gestion des collisions potentielles dans le trafic des signaux de commande. La Figure 1 représente la configuration physique de système prise en considération dans la présente norme. Plusieurs démodulateurs de signaux satellites peuvent recevoir des signaux issus de batteries de signaux d'entrée (Batterie 1, Batterie 2, Batterie M, avec M ≤ 256) du LNB ou du commutateur. Les signaux sélectionnés par les démodulateurs (ou récepteurs) sont transportés par un seul câble vers ces démodulateurs (Récepteur 1, Récepteur 2, Récepteur N, avec N ≤ 32). Pour réaliser ces distributions par un seul câble, l'interface à un seul câble (SCIF, vraisemblablement incorporée dans un LNB ou un commutateur) présente un certain nombre de fonctions et caractéristiques spécifiques.

Distribucija satelitskih signalov po enojnem koaksialnem kablu - Druga generacija

V tem evropskem standardu je opisano naslednje:
▪ fizična struktura sistema;
▪ kontrolni signali sistema, ki uvajajo nabor sporočil na podlagi fizične plasti DiSEqC in ne strukture sporočil DiSEqC;
▪ definicija prepoznanih konfiguracij;
▪ upravljanje morebitnih trčenj v prometu s kontrolnimi signali.
Slika 1 prikazuje konfiguracijo fizičnega sistema, ki jo obravnava ta standard.
Več demodulatorjev satelitskega signala lahko sprejema signale iz katerega koli vhodnega niza signalov (Niz 1, Niz 2, Niz M, pri čemer je M ≤ 256) LNB ali stikala. Signali, ki jih izberejo demodulatorji (ali sprejemniki), se prenesejo v te demodulatorje (Sprejemnik 1, Sprejemnik 2, Sprejemnik N, pri čemer je N ≤ 32) po enojnem kablu.
Za doseganje take distribucije po enojnem kablu ima vmesnik SCIF (Single Cable Interface, ki je verjetno vdelan v LNB ali stikalo) nekatere posebne funkcije in karakteristike.

General Information

Status
Published
Publication Date
08-Jan-2015
Current Stage
6060 - Document made available
Due Date
09-Jan-2015
Completion Date
09-Jan-2015

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SLOVENSKI STANDARD
SIST EN 50607:2015
01-maj-2015
1DGRPHãþD
SIST-TS CLC/TS 50607:2013

Distribucija satelitskih signalov po enojnem koaksialnem kablu - Druga generacija

Satellite signal distribution over a single coaxial cable - Second generation
Verteilen von Satellitensignalen über ein Koaxialkabel - Zweite Generation

Distribution de signaux par satellite sur un seul câble coaxial - Deuxième génération

Ta slovenski standard je istoveten z: EN 50607:2015
ICS:
33.060.40 Kabelski razdelilni sistemi Cabled distribution systems
33.120.10 Koaksialni kabli. Valovodi Coaxial cables. Waveguides
SIST EN 50607:2015 en,fr,de

2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

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SIST EN 50607:2015
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SIST EN 50607:2015
EUROPEAN STANDARD EN 50607
NORME EUROPÉENNE
EUROPÄISCHE NORM
January 2015
ICS 33.060.40 Supersedes CLC/TS 50607:2013
English Version
Satellite signal distribution over a single coaxial cable - Second
generation

Distribution de signaux par satellite sur un seul câble Verteilen von Satellitensignalen über ein Koaxialkabel ¿

coaxial - Deuxième génération Zweite Generation

This European Standard was approved by CENELEC on 2014-10-20. CENELEC members are bound to comply with the CEN/CENELEC

Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC

Management Centre or to any CENELEC member.

This European Standard exists in three official versions (English, French, German). A version in any other language made by translation

under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the

same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,

Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,

Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland,

Turkey and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Avenue Marnix 17, B-1000 Brussels

© 2015 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.

Ref. No. EN 50607:2015 E
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EN 50607:2015 ‒ 2 ‒
Contents Page

Foreword ............................................................................................................................................................. 3

Introduction ......................................................................................................................................................... 4

1 Scope ..................................................................................................................................................... 5

2 Normative references ............................................................................................................................ 5

3 Terms, definitions and abbreviations ..................................................................................................... 6

3.1 Terms and definitions ............................................................................................................................ 6

3.2 Abbreviations ......................................................................................................................................... 8

3.3 Used commands .................................................................................................................................... 8

4 System architecture ............................................................................................................................... 9

5 SCIF control signals............................................................................................................................. 12

5.1 DC levels ............................................................................................................................................. 12

5.2 Method of the data bit signalling .......................................................................................................... 14

6 Structure and format of the messages of the 2nd generation single cable distribution system (SCD2)14

6.1 Backwards Compatibility to EN 50494 ................................................................................................ 14

6.2 Non-DiSEqC structure ......................................................................................................................... 14

6.3 Uni-directional operation ...................................................................................................................... 15

6.4 Bi-directional operation ........................................................................................................................ 15

7 SCD2 commands ................................................................................................................................. 15

7.1 ODU_Channel_change ....................................................................................................................... 15

7.1.1 Formats ................................................................................................................................................ 15

7.1.2 “Special” frequencies ........................................................................................................................... 16

7.2 ODU_Channel_change_PIN ............................................................................................................... 16

7.3 ODU_UB_avail .................................................................................................................................... 17

7.4 ODU_UB_PIN ...................................................................................................................................... 18

7.5 ODU_UB_inuse ................................................................................................................................... 18

7.6 ODU_UB_freq ...................................................................................................................................... 19

7.7 ODU_UB_switches .............................................................................................................................. 20

8 Conventions ......................................................................................................................................... 21

8.1 UB slots numbering ............................................................................................................................. 21

8.2 Numbering of satellite IF banks ........................................................................................................... 22

9 Traffic collision management rules ...................................................................................................... 22

9.1 General ................................................................................................................................................ 22

9.2 Automatic detection of SCIF control signal failure ............................................................................... 22

9.3 Pseudo-random repeat ........................................................................................................................ 23

9.3.1 Handling of SCIF control signal ........................................................................................................... 23

9.3.2 Random delay generation law ............................................................................................................. 23

Annex A (normative) Implementation rules ..................................................................................................... 25

A.1 User interface ...................................................................................................................................... 25

A.2 Installation impedance ......................................................................................................................... 25

A.3 Signal reflection and return loss in installations .................................................................................. 26

A.4 Power supply of the SCIF .................................................................................................................... 26

A.5 Remarks concerning power supply ..................................................................................................... 27

Bibliography ...................................................................................................................................................... 28

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Foreword

This document (EN 50607:2015) has been prepared by CLC/TC 209 “Cable networks for television signals,

sound signals and interactive services”.
The following dates are fixed:
• latest date by which this document has (dop) 2015-10-20
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2017-10-20
standards conflicting with this
document have to be withdrawn
This document supersedes CLC/TS 50607:2013.

Attention is drawn to the possibility that some of the elements of this document may be the subject of patent

rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent rights.

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Introduction

In EN 61319-1:1996, the interfaces for the control and command of the devices associated with the satellite

receivers are described in the following clauses:
▪ Clause 4: Interfaces requirements for polarizer and polar switchers;
▪ Clause 5: Interfaces requirements for low-noise block converters (LNB).

In these clauses, analogue techniques are described for controlling the LNB and polar switchers.

In the DiSEqC Bus Functional Specification, the “Digital Satellite Equipment Control Bus” (called DiSEqC)

is introduced as a single method of communication between the satellite and the peripheral equipment, using

only the existing coaxial cables. The existing EN 50494 “Satellite signal distribution over a single coaxial

cable in single dwelling installations” describes a system for distributing signals via single coaxial cable

issued from different bands and polarisations to several satellite receivers This specification is limited to 8

units per output of the Single Cable Interface and to 8 Satellite IF banks (bands, feeds, polarisations).

The second generation described in this standard is intended for single and multiple dwelling installations

and includes the following enhancements compared to EN 50494:

▪ The number of demodulators is extended to a maximum of 32 units per output of the Single Cable

Interface (hereafter referred to as SCIF) device.

▪ The system is scaled for a maximum number of 256 Satellite IF banks (bands, feeds, polarisations)

▪ The SCIF replies, which may be used during installation process, are also based on DiSEqC.

▪ Equipment according to this standard is downwards compatible to the specifications provided by

EN 50494.
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1 Scope
This European Standard describes:
▪ the system physical structure;

▪ the system control signals, which implement a set of messages using DiSEqC physical layer but not the

DiSEqC message structure;
▪ the definition of identified configurations;
▪ the management of the potential collisions in the control signals traffic.

Figure 1 illustrates the physical system configuration considered in this standard.

Several satellite signal demodulators can receive signals from any of the input signal banks (Bank 1, Bank 2,

Bank M, with M ≤ 256) of the LNB or the switch. The signals selected by the demodulators (or receivers) are

transported via a single cable to these demodulators (Receiver 1, Receiver 2, Receiver N, with N ≤ 32).

To achieve these single cable distributions, the Single Cable Interface (SCIF, likely embedded in a LNB or a

Switch) features some specific functions and characteristics.
Figure 1 — General architecture of the single cable distribution
2 Normative references

The following documents, in whole or in part, are normatively referenced in this document and are

indispensable for its application. For dated references, only the edition cited applies. For undated references,

the latest edition of the referenced document (including any amendments) applies.

EN 50494, Satellite signal distribution over a single coaxial cable in single dwelling installations

EN 60728-1, Cable networks for television signals, sound signals and interactive services – Part 1: System

performance of forward paths (IEC 60728-1)

EN 60728-4, Cable networks for television signals, sound signals and interactive services – Part 4: Passive

wideband equipment for coaxial cable networks (IEC 60728-4)

EN 61319-1:1996, Interconnections of satellite receiving equipment – Part 1: Europe (IEC 61319-1:1995)

IEC 60050-371, International Electrotechnical Vocabulary - Chapter 371: Telecontrol

IEC 60050-721, International Electrotechnical Vocabulary - Chapter 721: Telegraphy, facsimile and data

communication
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TM 1
DiSEqC Bus Functional Specification, Version 4.2, February 25, 1998
3 Terms, definitions and abbreviations
3.1 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60050-371, IEC 60050-721,

EN 60728-1 and the following ones apply.
3.1.1
bank
group of contiguous channels belonging to a polarisation and/or a band
3.1.2
channel
radio frequency transponder signal
3.1.3
command

information used to cause a change of state of operational equipment; could be part of message

[SOURCE: IEC 60050-371:1984, 371-03-01, modified]
3.1.4
committed switch
switch with specified functions (band, polarity, position, option)
3.1.5
demodulator
electronic device transposing the selected channel into the required content
3.1.6
idle mode
operation mode on low DC level
3.1.7
message

group of characters and function control sequences which is transferred as an entity from a transmitter to a

receiver, where the arrangement of the characters is determined at the transmitter

[SOURCE: IEC 60050-721:1991, 721-09-01]
3.1.8
multi dwelling unit
MDU

building with many homes or offices used by single owners where television signals and sound signals are

distributed and with access to interactive services
[SOURCE: IEC 60728-1:2014, 3.1.64, modified]
3.1.9
nibble
half byte
Available from http://www.eutelsat.com/satellites/4_5_5.html
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3.1.10
receiver

electronic equipment embedded in a cabinet and integrating all functions for demodulating and decoding the

received satellite signals (a receiver may integrate several demodulators)
3.1.11
SCIF control signal

signal sent by the demodulator to select the bank and the frequency of the desired channel and to designate

the UB slot allocated to the requesting receiver
3.1.12
single cable interface
SCIF

central unit of a single cable distribution system which selects the desired channels from different banks at

its input ports and allocate them to the designated UB slots at its output port
3.1.13
single dwelling installation

installation for a home or office used by a single owner where television signals and sound signals are

distributed and there is access to interactive services
3.1.14
tuning word

information carried by the command ODU_Channel_change to select the desired channel in the SCIF

3.1.15
uncommitted switch
switch without specified functions
3.1.16
universal architecture

LNB with the following characteristics: operation in the Ku band (10,7 GHz to 12,75 GHz); local oscillator

frequency is 9,75 GHz for signal frequencies lower than 11,7 GHz and local oscillator frequency is 10,6 GHz

otherwise
3.1.17
user band

part of the bandwidth of the shared coaxial cable which is allocated to one receiver connected to the single

coaxial cable distribution system for the reception of the desired channel
3.1.18
user band slot
UB slot
one of N bands in which the total transmission bandwidth is sub-divided

Note 1 to entry: The number of user band slots Nb_ub is a characteristic of the SCIF used.

Note 2 to entry: The system defined in this standard limits the number of UB slots to 32 per output of the SCIF.

3.1.19
wideband architecture

LNB with the following characteristics: operation in the Ku band (10,7 GHz to 12,75 GHz); with only one local

oscillator. Universal-LNB functionality is emulated by the SCIF by adding or subtracting an offset for

frequency conversion according to lowband/highband selection
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3.2 Abbreviations
CSS Channel Stacking System
CW Continuous Wave
DC Direct Current
DiSEqC Digital Satellite Equipment Control
High_DC High level of DC voltage DC
High
IF Intermediate Frequency
LNB Low Noise Blockconverter
Low_DC Low level of DC voltage DC
Low
LSB Least Significant Bit
MDU Multiple Dwelling Unit
MSB Most Significant Bit
Nb_B Number of Banks Nb
Nb_ub Number of user bands Nb
ODU Out-Door Unit
PCR Program Clock Reference
PIN Personal Identification Number
PWK Pulse Width Keying
SCD2 Single Cable Distribution 2 (second generation)
SCIF Single Cable Interface
STB Set-Top Box
UB User Band
UB-ID User Band Identifier
3.3 Used commands

ODU_Channel_change Unidirectional command sent by the receiver for tuning to a required channel

ODU_Channel_change_PIN Option for PIN protection of UB in the ODU_Channel_change command

ODU_PowerOFF Unidirectional command sent to SCIF before the receiver turns into standby

ODU_PowerOFF_PIN Unidirectional command to turn-off the PIN protected UB slot

ODU_UB_avail Bidirectional command for requesting information about user bands available

ODU_UB_frequ Bidirectional command for requesting the centre frequency of a specific user

band

ODU_UB_inuse Bidirectional command for requesting information about user bands currently

in use

ODU_UB_PIN Bidirectional command for requesting information about PIN protected user

bands

ODU_UB_switches Bidirectional command for requesting information about the available bank

switches of a specific user band

ODU_UBxSignal_ON Command from a receiver, specified in EN 50494, which causes the SCIF to

switch on CW tones at the centre of all (maximum 8) user bands
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4 System architecture

In the single coaxial cable distribution system, the bandwidth of the shared coaxial cable is divided into slots

(user band: UB). The number of slots Nb_ub varies from one application to another; the number of slots

Nb_ub is a characteristic of the SCIF.

The system defined in this standard limits the number of UB slots to 32 per output of the SCIF.

Each receiver connected to the single coaxial cable distribution is allocated to one UB slot. This allocation is

done either in static or other modes.

In the static mode, the allocation of the UB slot is done during the installation of the satellite receiver. Only

the static mode is considered in this document.

NOTE Other modes are not described in this document but could be considered in a further release or annex of this

standard.

After the slot allocation, the tuner of the receiver operates at a single frequency (centre of the slot UB). To

select a desired channel (frequency Fd), the demodulator sends a SCIF control signal that provides the

following information:
▪ select the bank (band, feed, polarization) that carries the desired signal;
▪ select the frequency (Fd) of the desired signal;
▪ designate the UB slot on which the desired signal is expected.

Figure 2 illustrates the frequency mapping for such a single coaxial cable system.

Figure 3, Figure 4, Figure 5 and Figure 6 illustrate various examples for implementing the single cable

distribution system (other application scenarios are possible).
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SCIF
inputs
SCIF
output
Figure 2 — General system operation and UB slot frequency mapping
BBanank 1k 1
Power
Power
spsplliitttterer
BBanank 2k 2
RReceieceivverer 11
SCIF
SCIF
BBanank 3k 3
RReceieceivverer 22
BBanank 4k 4
NNuummbbeerr o off bbaannkkss = = N Nbb__BB == 4 4
NNuummbbeerr o off uusseerr s slloottss = = N Nbb__ubub = = 2 2
Figure 3 — Installation example, universal architecture system
with reception of one orbital position (4 Satellite IF banks)
by two receivers (2 UB slots)
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Key
Number of banks Nb_B = 2
Number of user slots Nb_ub = 2
Figure 4 − Installation example, wideband architecture system
with reception of one orbital position (2 Satellite IF banks)
by two receivers (2 UB slots)
BBanank 1k 1
SSaatteellitllitee
BBanank 2k 2
RReceieceivverer 11
Power
Power
BBanank 3k 3
splitter
splitter
Receiver 2
Bank 4 Receiver 2
Bank 4
SSCICIFF
BBanank 5k 5
Satellite
Satellite
BB RReceieceivverer 33
BBanank 6k 6
RReceieceivverer 44
BBanank 7k 7
BBanank 8k 8
Number of banks = Nb_B = 8
Number of banks = Nb_B = 8
NNuummbbeerr o off uusseerr s slloottss = = N Nbb__ubub = = 4 4

Figure 5 — Installation example implementing the reception of two orbital positions

(8 satellite IF banks) by four receivers (4 UB slots)
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Figure 6 — Installation example implementing the reception of four orbital positions

(16 satellite IF banks) for 12 receivers (12 UB slots)
5 SCIF control signals
5.1 DC levels

In a single coaxial cable distribution system, all controls issued by the receivers (demodulators) use the

DiSEqC physical layer.

The single coaxial cable distribution system is not backwards compatible with the former 13/18 V control

associated with a continuous 22 kHz tone. The single coaxial cable distribution system is also not backwards

compatible with the tone burst signalling.

In single coaxial cable distribution systems, the signal-sending receiver generates a high DC level upon

which the SCIF control signals are added. After sending the SCIF control signal, the receiver returns to an

idle mode in which it generates a low DC level onto the single cable distribution system (see Figure 7). With

reference to the DiSEqC Bus Functional Specification, the low and high DC level shall have the following

limits on the signal-sending-receiver side:
▪ LOW_DC value: 12,5 V to 14 V;
▪ HIGH_DC value: 17 V to 19 V.

For uni-directional communication (DiSEqC level 1.0; based on the DiSEqC Bus Functional Specification),

the timing shall have the following limits according to Table 1:
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Table 1 — Timing for unidirectional communication
Time period Minimum Maximum Description
duration duration
[ms] [ms]
T1+T2 22 Rise Time and Setup Time
T2 2 Setup time
T3 54 67,5 13,5 ms per byte
T4 2 Wait time after end of DiSEqC message
(T3)
T4+T5 40 Fall time and Wait Time
T1 up to T5 129,5
Figure 7 — Signal sent by the receiver for uni-directional communication

In Clause 7, the channel-change commands (70/71 in Figure 7) are described in detail.

After each uni-directional message, SCIF reply or reply timeout, the voltage shall return to “LOW_DC” before

sending another message (see Figure 7).

For bi-directional communication (DiSEqC level 2.0; based on the DiSEqC Bus Functional Specification),

the timing shall have the following limits according to Table 2:
Table 2 — Timing for bidirectional communication
Time period Minimum Maximum Description
duration duration
[ms] [ms]
T1+T2 22 Rise Time and Setup Time
T2 2
T3 13,5 27 13,5 ms per byte
T4 15 25 Return to Low DC after Timeout of
50 ms (receiver)
T5 40,5 67,5 13,5 ms per byte
T6 2 Wait Time after DiSEqC message (T5)
T6+T7 40 Wait Time and Fall Time
T1 up to T7 181,5
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NOTE Maximum 4 Data Bytes due to 32 UB slots in reply.
Figure 8 — Signal sent by the receiver for bi-directional communication

In Clause 7, the Config and Reply commands (7A-7E and 74xx… in Figure 8) are described in detail. The

hardware of the communication bus shall be realized according to the DiSEqC Bus Functional

Specification. Some additional care shall be taken to ensure an appropriate impedance of the installation

during the SCIF control signals. In Annex A, some implementation rules are given.

5.2 Method of the data bit signalling

DiSEqC uses base-band timings of 500 µs (±100 µs) for a one-third-bit PWK coded signal on a nominal

22 kHz (± 4 kHz) carrier according to the DiSEqC Bus Functional Specification. Figure 9 shows the 22 kHz

time envelope for each bit transmitted, with nominally 22 cycles for a bit “0” and 11 cycles for a bit “1”.

Figure 9 — Bit signalling according to DiSEqC format
6 Structure and format of the messages of the 2nd generation single cable
distribution system (SCD2)
6.1 Backwards Compatibility to EN 50494

For compatibility reasons all SCIF devices supporting SCD2 shall also include the corresponding

functionality of EN 50494.
6.2 Non-DiSEqC structure

SCD2 uses DiSEqC physical layer, but a non-DiSEqC message structure optimised for single cable

operation.

FRAMING: the framing is reduced to the first four bits (7 to 4) of the first byte. The value is “7 h”. Commands

with this framing will be ignored by known DiSEqC slaves.

ADDRESS: as remote tuning systems only have one slave there is no addressing of multiple devices

required, and therefore the DiSEqC address scheme is not used.
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COMMAND: the commands are already transmitted in the lower nibble of the first byte (.3 to 0,0).

The length of the complete message can vary between one byte only and eight bytes.

6.3 Uni-directional operation

Uni-directional operation is used for regular tuning commands such as “70 h” and “71 h”. Voltage levels and

timings are defined in Figure 7.
6.4 Bi-directional operation

Bi-directional operation may be used for receiver installation purposes. Voltage levels and timings are

defined in Figure 8. To use bi-directional communication, hardware according to DiSEqC level 2.0 in the

DiSEqC Bus Functional Specification shall be used (see A.2). Receivers shall send the request on the

“HIGH_DC” and hold this high DC level until either the reply was received or 50ms after the request have

passed (timeout condition). In case of improper reply, the receiver may send the request up to five times

using the repeat mechanism described in Clause 9.

Support of bidirectional operation is optional for the receiver and mandatory for the SCIF.

7 SCD2 commands
7.1 ODU_Channel_change
7.1.1 Formats

The receiver uses this uni-directional command when tuning to a (new) channel is required. Timing is

described in Figure 7.
ODU_Channel_change format:
70h Data 1 Data 2 Data 3
Data 1 format:
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
UB [4:0] T [10:8]
Data 2 format:
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
T [7:0]
Data 3 format:
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
“Uncommitted switches” ”Committed switches”

▪ UB [4:0] bits select the UB slot on which the desired signal is expected (Userband-ID).

▪ “Uncommitted switches” is extended satellite selection known from DiSEqC 1.1. Lower data nibble of

DiSEqC command “39h” can be mapped in here (“uncommitted switch 1” is Bit 4).

▪ “Committed switches” is the band (.0), polarity (.1), position (.2) and option (.3) bits known from

DiSEqC 1.0. Lower data nibble of DiSEqC command “38h” can be mapped in here (“band” is LSB).

▪ The T[..] word is the tuning word calculated by the receiver as follows:
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T = F – 100
where
T is the decimal value of the tuning word T[..]. (see above);

F is the IF frequency in MHz (where the tuner would tune to when connected directly);

100 is the constant value used to compress the T[..] word.
7.1.2 “Special” frequencies
Some frequencies are defined as contro
...

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