Wood and Douglas ORION RADIO MODEM WITH I/O User manual

1892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009 1
ORION RADIO MODEM WITH I/O
OPERATING INSTRUCTIONS
1892 1335
Figure 1 - Orion Radio Modem
Figure 2 - Orion Radio Modem - OEM PCB version

21892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009

1892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009 3
Contents
Contents ........................................................ 3
INTRODUCTION TO THE ORION AND ITS USES ........................ 5
FEATURE OVERVIEW ............................................. 5
Part One - the Orion Unit ................................................ 7
ORION MODES ................................................... 9
Mode U - Data Only ........................................................... 10
Mode R - Repeater ........................................................... 10
Mode I - Independent Telemetry .................................................10
Mode E - Externally-controlled Telemetry ..........................................12
Mode L - Data Logging ........................................................13
ADDRESSING ................................................... 14
ALARMS AND ALERTS ............................................ 16
Failsafe Feature ..............................................................17
SERIAL INTERFACE CONFIGURATION .............................. 19
AT commands ...............................................................19
Graphical User Interface (GUI) and SCADA ........................................19
TELEMETRY CONFIGURATION .................................... 20
Common Parameters (MI and ME) ...............................................20
Mode I Parameters ........................................................... 20
Mode E Parameters ..........................................................22
Mode L Parameters ...........................................................23
USER DATA CONFIGURATION ..................................... 24
Mode U Parameters ..........................................................24
More information about User Data queuing behaviour ................................24
REPEATER CONFIGURATION ...................................... 26
Mode R Parameters ..........................................................26
RADIO CONFIGURATION .......................................... 27
Interaction between Centre Frequency, Channel Number and Operating Frequency .........27
OVER-AIR PROTOCOL ............................................ 27
Protocol Selection ............................................................28
Symbol Rate ................................................................ 28
Hold-off Before Transmitting .................................................... 28
OPTIONS WHEN ORDERING ...................................... 29
OEM PCB version ............................................................29
Modem Only version .......................................................... 29
INSTALLATION .................................................. 30
Physical ....................................................................30
Connections .................................................................32
Earthing and Equipment Protection ...............................................34
INDICATIONS DURING OPERATION ................................. 35
TEST AND FAULT-FINDING FACILITIES .............................. 36
Get Information ..............................................................36
Send Test Signals ............................................................ 36
Restore Factory Settings .......................................................36
GUI Status Messages .........................................................37
Memory ....................................................................38
Part Two - the Graphical User Interface (GUI) .............................. 39
INTRODUCTION TO THE GRAPHICAL USER INTERFACE (GUI) .......... 41
Software Installation .......................................................... 41
Notes on GUI Operation .......................................................41
Passwording ................................................................41
CONNECTING THE GUI TO AN ORION ............................... 42
CONFIGURATION MANAGEMENT .................................. 44
File Menu - load and save configurations to disk ....................................44

41892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009
Link Menu - load and save configurations to and from an Orion unit ...................... 44
Remote Menu - load and save configurations to a remote unit .......................... 45
SERIAL INTERFACE PARAMETERS ................................. 46
MODES, PROTOCOLS AND ADDRESSING ........................... 46
Orion Modes ................................................................46
Addressing ..................................................................47
Over-Air Protocols ............................................................47
TELEMETRY CONFIGURATION .................................... 47
Polling .....................................................................48
General Alarm Parameters ..................................................... 48
Analogue In/Out Configuration ...................................................49
Analogue Alarms .............................................................50
Digital Configuration ..........................................................50
Digital Alarms ...............................................................51
GENERAL PARAMETER CONFIGURATION ........................... 52
Factory-set Parameters ........................................................52
User-set Parameters ..........................................................52
Additional Logging Parameters ..................................................54
RADIO FREQUENCY ............................................. 55
RADIO PARAMETERS ............................................ 56
User Option .................................................................56
Radio Parameters ............................................................56
DATA LOGGING USING THE GUI ................................... 57
TROUBLESHOOTING AND MAINTENANCE ........................... 58
Firmware update ............................................................ 58
Re-programming with Factory settings ............................................58
Local Tests ................................................................. 58
Help .......................................................................60
Part Three - Appendices ............................................... 61
APPENDIX A: AT COMMAND REFERENCE ........................... 63
Entering Command Mode (+++) .................................................63
Command Syntax ............................................................ 64
Ending Command Mode (ATO) ..................................................65
A Note About Baud Rate ....................................................... 66
AT Commands and Parameters Reference ........................................ 67
APPENDIX B: OVER-AIR COMMAND CODES .......................... 75
Summary of Messages and Responses ...........................................75
Message Syntax .............................................................76
APPENDIX C: ATT? PARAMETER STRING STRUCTURE ................ 81
APPENDIX D: SERIAL TO USB ADAPTOR ............................ 85
Installing the Adaptor ..........................................................85
Connecting the Command Centre PC and the Orion ................................. 85
Checking Correct Operation ....................................................85
APPENDIX E: SPECIFICATIONS .................................... 86
APPENDIX F: DIN RAIL MOUNTING ACCESSORIES .................... 88

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INTRODUCTION TO THE ORION AND ITS USES
The Orion is a flexible unit designed to help you build point-to-point links and Base station-to-
multiple-Outstation networks, carrying serial user data, telemetry information, or both. In
simpler configurations, no additional equipment is required.
Each unit contains a modem and a transceiver, which can be ordered according to the
frequencies and range required.
The Orion’s particular feature is the provision of a small number of on-board analogue and
digital inputs and outputs in addition to serial data in/out. Where only serial data is required,
a model without these telemetry functions can be ordered.
Addressing allows one or more point-to-point links and networks to operate on the same
frequency, each Orion being able to handle both serial data communication and telemetry on
a time-sharing basis.
A repeater mode allows an Orion to relay data and telemetry messages for a group of units to
extend useful range.
In straightforward one-to-one (also known as back-to-back or mimic) and one-to-many
situations, the Orion can supervise polling, alarms etc. unaided. External control can be
added for more complex polling or SCADA (Supervisory, Control And Data Acquisition)
functions.
An Orion unit’s features and operating modes are user-programmable by using supplied
configuration software (a Graphical User Interface or GUI) running on a PC and covered in
Part Two of this manual; but it is also possible to configure the unit locally using AT
commands or remotely using special over-air commands, both listed in appendices in Part
Three of this manual.
FEATURE OVERVIEW
Figure 3 - Orion block diagram

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The Orion is a radio modem with on-board telemetry inputs and outputs. It also contains
supervisory software which supports links and addressed networks. It is available in a
number of different versions to suit different applications, and has many user-programmable
features, which may be locally or remotely set.
Figure 3 shows the Orion in block diagram form.
Summary of notable features and options:
vFive modes to support different ways of working
vFour digital inputs, which may be used as pulse counters
vPTT facility to assist testing
vFour digital outputs
vFour analogue inputs (current loop or voltage)*
vFour analogue outputs (current loop or voltage)*, any one of which may be used
as an RSSI (signal strength) output
vFailsafe levels can be applied to outputs on system failure
vAlert output - pull-down to 0V or floating relay contacts option
vTwo serial ports handling User Data, telemetry (I/O, SCADA) and AT
(configuration) commands
vSerial Port A can be soft-configured for RS232, RS422 or RS485; Serial Port
B is RS232.
vSampling mode transmits any binary data format
vUnidirectional or half-duplex link, choice of error correction
vChoice of frequency band and power
vAT command set, local or remote programming of most features
vOne-to-one or Base + Outstations configurations with addressing
vOutstations can be polled and/or volunteer data when thresholds are reached
(‘alarms’).
vGraphical User Interface (GUI) software supplied for configuration
*The four analogue ports can also be used to relay digital data if required,
depending on the application.

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Part One - the Orion Unit

81892 1335 - Orion Radio Modem Operating Instructions - v2.9 / Aug 2009

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ORION MODES
The Orion supports five modes of operation to enable you to build exactly the link or network
you want. They are:
vU - User Data only
vR - repeater
vI - independent (standalone) telemetry + User Data
vE - externally-controlled telemetry + User Data
vL - data logging
Depending on the mode you select, other features become available. Addressing is
available in all modes - see page 14.
This section (pages 10 to 13) describes the network topologies and features of each mode.
Further sections (pages 14 to 27) describe the corresponding features and parameters in
detail.
AT codes are shown in this Part of the manual only to pinpoint the precise command referred
to. The AT Command Reference is to be found on page 63 onwards.

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Mode U - Data Only
The Orion can be used as a high-performance data modem without using its built-in telemetry
capabilities, and can be ordered without telemetry hardware at a saving in cost. Mode U
supports half-duplex or simplex serial User Data communication via Serial Port A.
Typically, two modems will communicate half-duplex, but other topologies are possible:
vUsing the address facilities of the Orion, many such pairs may share a
frequency (on a time-sharing basis).
vMany modems may report data one at a time to a central modem provided
traffic is relatively light, or one modem may broadcast to all the others.
There is no concept of Base and Outstation because each modem initiates transmission
when it has data, rather than being polled. Addressing is described in detail on page 14
Depending on the throughput required and the level of errors which can be tolerated, different
over-air protocols may be selected. These are described on page 27.
Port A may be configured for various serial interfaces. See pages 19 (description) and 33
(connections).
Mode U parameters are covered on page 24, and radio configuration on page 27.
Contention can be dealt with / overcome by using a packet over-air protocol with
acknowledgements or by external equipment.
Mode R - Repeater
In order to extend the range of a link or network, an additional Orion (one per Group) can be
used as a repeater. Set to Mode R, it stores any message it receives for a member of its
Group and retransmits it without alteration. A duplicate message received by any unit is
recognised as such and ignored.
A repeater has an extremely limited range of behaviours, but can be programmed to raise
housekeeping alarms (page 16). It must belong to the same Group as it serves.
No telemetry or User Data input/output is available at the Repeater itself.
A repeater can be used in a network which uses any over-air protocol except Packet (TP),
but must be set for the same protocol as the units which it serves. Over-air protocols are
described on page 27.
Mode I- Independent Telemetry
The Orion has four digital inputs and outputs and four analogue inputs and outputs. Mode Iis
used where these inputs and outputs simply need to be relayed from one location to another,
and no external SCADA (Supervisory, Control And Data Acquisition) equipment is to be
used. User Data can still be carried in addition to the telemetry.
The simplest arrangement is a one-to-one link where inputs at one end are mimicked at the
other end and vice versa. Two ways of working are possible:
vEach unit volunteers any change in its inputs to the other spontaneously, and the
other replies with an acknowledgement

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vOne unit polls the other, volunteering its inputs, and the other replies with its
inputs. Each then mimics the other’s inputs on its outputs.
In either of these arrangements, alarms are sent spontaneously under predefined conditions
unless suppressed, and are acknowledged by the other unit. See page 16.
It is also possible to run a one-to-all topology in this mode, where the Base unit broadcasts its
inputs regularly, and all other units duplicate them on their outputs. This results in a one-way
telemetry link, although two-way User Data is still possible among the units.
vAlarm transmission must be suppressed at the Outstations since the Base is
unable to output them.
vWhen a broadcast is made, no acknowledgements are returned by the
Outstations nor expected by the Base.
Figure 4 illustrates the two polled arrangements.
Figure 4 - One-to-one and Broadcast polling in Mode I
Frequency of polling can be set over a wide range, from 100ms up to just over a week.
The over-air protocol is fixed and used for both User Data and telemetry.
If a unit expects a response and fails to get it, it can transmit an alarm message, operate alert
contacts, and set its outputs to predefined failsafe values. See page 16.
These topologies are achieved by setting unit addresses to the correct values. See page 14.

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Mode E - Externally-controlled Telemetry
This mode is used where the inputs and outputs at many Outstations are individually
interrogated and controlled by external SCADA equipment at a Base station. The Base unit
relinquishes most of its functions to the SCADA equipment, which controls polling,
input/output, acknowledgements, retries and alarm handling via Serial Port B. In order to do
this, it must use the message protocol described in Appendix B on page 75.
The Base unit provides no telemetry input/output, nor does it send alarm messages, but User
Data is available independently as for the other modes, on Serial Port A.
Outstations in Mode E behave as for Mode I, returning input information and obeying output
commands in response to polls, except that input information is never spontaneously
volunteered. Alarms, however, are spontaneously volunteered if they are set and the unit is
set to permit initiation of transmissions. The SCADA must acknowledge any alarm sent to it
to avoid raising a Comms Alarm at the Outstation. See page 16 for more details.
Unlike Mode I, where broadcast is a distinct configuration, the SCADA may broadcast
whenever it wishes. Outstations never acknowledge broadcast messages in any Orion
mode.
Figure 5 illustrates the one-to-many topology.
Figure 5 - One-to-many topology with external SCADA
The over-air protocol is fixed and used for both User Data and telemetry.

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Mode L - Data Logging
Logging mode is used where equipment at many sites produces information, and there is a
need to retrieve it periodically from a central location. At each site, an Orion Outstation stores
serial data presented to Serial Port A, and relays it to the Base when it is polled. The Base
polls addresses between one and the total number of sites, receiving the data and outputting
it on Serial Port A which is connected to external logging equipment. Alternatively, the data
may be output to Serial Port B and recorded to disk by the supplied GUI software.
vNeither a separate User Data channel nor telemetry input/output is available in
this mode.
Figure 6 illustrates the topology.
Figure 6 - One-to-many logging topology with Orion polling
The over-air protocol is fixed and transparent to the user.

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ADDRESSING
In order that you can create systems containing two or more Orions, or even several separate
systems, all on the same frequency, the Orion supports addressing. This works by having one
or more groups each containing between two and 254 Orion units. Each Orion bears the
number of a group to which it belongs, and its own unique number within that group. By
including both IDs in a message, it is possible to identify the specific unit for which a message
is intended. The sending unit’s identity is also included with the message so that the unit can
reply.
Each Group has a GroupID of between 1 and 254. (The remaining two values, 0 and 255,
are reserved for special purposes.) You can assign units to a Group by giving the same
GroupID to all of them.
Each Group has one Base unit defined by having the UnitID 0 (zero). Other units in the Group
must be designated as Outstations by entering a UnitID of 1 to 254, unique within the Group.
(The remaining value, 255, is reserved for special purposes and never used as a UnitID.)
With exceptions treated below, units only respond to messages addressed with their own
GroupID and UnitID.
Units also have a DestinationID (DestID), which is the address (UnitID) to which they will send
any message (User Data or telemetry) which they initiate. When replying, a unit always
addresses the unit which sent the message: DestID is not used.
Example:
Two Orions are used as a two-way link for User Data between A and B
Orion A: Base: GroupID=1, UnitID=0, DestID=1
Orion B: Outstation: GroupID=1, UnitID=1, DestID=0
Unit A sends a message containing the address “GroupID:1, DestID:1, SourceID:0" It
has inserted its own GroupID; its DestID as the unit to receive the message; and its
own UnitID as the source of the message.
Unit B receives the message and accepts it, because GroupID and DestID match its
own GroupID and UnitID.
Unit B needs to reply, so constructs a message with its GroupID, a destination not of its
own DestID, but of the SourceID of the incoming message; and its own UnitID as the
source of the message.
The DestID 255 has the special meaning of a broadcast, and messages with this address are
accepted by all units in the same Group. Broadcast messages are never acknowledged or
replied to, even if the system is set up to acknowledge normal messages.
vTherefore, Broadcast messages must not be used when Packet over-air
protocol is used.
The GroupID 0 causes a message to be accepted by all units except repeaters, ignoring both
GroupID and DestinationID - that is, the network does not use addressing at all.
vThis code is not intended for use as the GroupID of telemetry Outstations, which
should send messages only to the Base.

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vGroup 0 messages are treated as broadcast, and are not acknowledged or
replied to. Therefore they must not be used when Packet over-air protocol is
used.
vRepeaters ignore messages with GroupID 0.
GroupID 255 is reserved for future use, and is not a permitted value at present.
Identities can be set with the following commands (see p.63 for detailed information):
ID GroupID UnitID DestID
Set by ATS169 ATS170 ATS171

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ALARMS AND ALERTS
vAlarms and Alerts only apply where there are telemetry inputs and outputs, and
therefore only to Modes Iand E.
An alarm is a state where an input has fulfilled a specified condition in terms of magnitude,
logic state, time etc. which requires some action such as sending a message. An alarm can
be raised, persist for a time, and then clear. There are two types in the Orion:
vTelemetry alarms
vHousekeeping alarms
Telemetry alarms relate to telemetry inputs. They can be defined in terms of input state and
history, and turned on and off.
Housekeeping alarms relate to communications problems and unit powering.
An alert is a non-telemetry output which may be asserted in response to an alarm being
raised, for a programmable period, typically to draw an operator’s attention to a problem.
An alarm message is normally sent when an alarm is first raised, and then again when it
clears. However, this behaviour can be suppressed by telling the unit that it may not initiate
transmissions.
If an Outstation sends an alarm message, it always expects an acknowledgement from the
Base. If it doesn’t get one, it may try again one or more times, and then if no
acknowledgement results, it will raise a comms failure alarm.
The table below summarises the parameters which define each alarm, and what conditions
lead to the alarm being raised or cleared.
Note: some AT commands have several parameters controlling related functions. Syntax and other details are
contained in the AT Parameter Reference on page 63.
Alarm Parameters Raise conditions Clear conditions
Digital input
(ATS312nwhere
n is input number
1-4)
State deemed to
be an alarm
Dwell time
On/off
Input transits to
nominated state and
stays there for the dwell
time
Input returns to original
state and stays there for
the dwell time
Count input
(ATS312nwhere
n is input number
1-4)
Alarm Count
On/off
Nominated count is
reached Counter is reset
Analogue input
(ATS302nwhere
n is input number
1-4)
Polarity
(rising/falling)
Alarm level
Dwell time
On/off
Input rises/falls, reaching
or passing nominated
level and stays there for
the dwell time
Input returns above or
below nominated level
and stays there for the
dwell time

Alarm Parameters Raise conditions Clear conditions
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Comms Poll period time
(0=off) (ATS183)
and tolerable
number nof
missing
messages
(ATS184)
Ack is not received to n
polls (Base) or poll is not
received within poll time
+ 3s for nconsecutive
periods (Outstation) Next poll is received
Number of
message
attempts (alarm,
spontaneous or
poll) (ATS185)
Acknowledgement is not
received to the set
number of consecutive
attempts to send a
message to unit n.
A message is received
from unit n.
Power
(ATS172)
High level (0=off)
High dwell time
Low level (0=off)
Low dwell time
External supply voltage
exceeds either limit for
applicable dwell time.
External supply comes
back within limits for
applicable dwell time.
The Alert output can be set to respond to telemetry alarms, housekeeping alarms or both, or
switched off entirely (ATS337). The time for which it latches on can be set from 0 to just over
10 minutes in 10ms increments (AT336). Alert output and permission to transmit an alarm
message are independently controlled.
Failsafe Feature
In the event of a housekeeping alarm (Comms Alarm or Low/High Supply Alarm), telemetry
outputs can be made to take on failsafe values until normal operation is resumed. The failsafe
values may be individually programmed, and failsafe behaviour turned on and off using a
master setting.
Master Failsafe
control (ATS188)
Enables or disables Failsafe behaviour for the whole unit.
Digital outputs
(ATS318nwhere
n is input number
1-4)
Each digital output can be programmed with:
Failsafe/no failsafe
Failsafe behaviour: Stay as you are (default) Go low
Go high
Analogue outputs
(ATS305nwhere
n is input number
1-4)
Each analogue output can be programmed with:
Failsafe/no failsafe
Failsafe behaviour: Stay as you are (default)
Go to the specified level 1-1023

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Before going into failsafe mode, the unit transmits a message announcing that it will go into
this mode unless a poll is received within a programmable time. If the poll is received, it
responds in the usual way and goes back to normal operation. Otherwise it goes into failsafe
mode.
When the alarm clears again, the outputs stay as they are until a poll provides new output
information.

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SERIAL INTERFACE CONFIGURATION
The Orion has no user-selectable switches or links, but is fully programmable via its serial
data ports, using either the supplied Graphical User Interface described in Part Two of this
manual, or the AT commands listed in Part Three. The serial ports are the same ones used
during operation for User Data, SCADA and I/O.
Serial port connections are shown on page 33, and port parameters below.
vIf your computer has no serial port, you need to use your computer’s USB port
and a serial-to-USB adaptor: see Appendix D on page 85, 86.
vThe main reason for failure to connect to an Orion is that your terminal
equipment is not set to the same protocols as the serial port which it is
connected to (default 38400bps, no parity).
Serial Port A – User Data and AT Commands
Hardware mode (ATB2) Six combinations of interface and flow control are available:
RS232 with RTS/CTS, Xon/Xoff or no handshake;
RS422 with Xon/Xoff or no handshake; or
RS485 with no handshake.
The default is RS232 with no handshake.
Baud rate (ATB0) 1200, 2400, 4800, 9600, 19200, or 38400 (default)
Data bits (ATB5) 7 or 8 (default)
Parity (ATB1) Even, odd or none (default)
Serial Port B – GUI, Telemetry (SCADA) and AT Commands
Hardware mode Fixed RS232 with no handshake.
Baud rate (ATB3) 9600, 19200, or 38400 (default)
Data bits Fixed 8
Parity (ATB4) Even, odd or none (default)
AT commands
Either Serial Port A or Serial Port B can be used for AT commands, provided the sending
equipment is correctly connected and configured for the hardware mode. Matching
parameters (baud rate etc.) must be selected at the Orion and the sending equipment. AT
commands consist of ASCII characters passed in either direction, so a special access
sequence is used to ensure that they are not confused with data. See page 63.
Graphical User Interface (GUI) and SCADA
The GUI or SCADA equipment can only be connected to Serial Port B. This is never used for
User Data, and hence no special access arrangements are needed. The PC is connected to
the Orion and communicates with it using a proprietary language.

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TELEMETRY CONFIGURATION
There are three basic telemetry modes, MI, ME and ML, with variations as explained on
pages 10 to 13. This section looks at the parameters which are common to several modes,
and the parameters which are mode-dependent.
Common Parameters (MI and ME)
Analogue input scaling (four inputs,
individually set) (ATS300n)
0-2.5V, 0-5V, 0-10V, 0-20mA*
Digital input
Low = closing contact or 0V
High = open circuit or 3.3V to 12V
No configuration required
Digital input type (four inputs, individually
set) (ATS312n)
Logic input or pulse counter
Analogue output scaling (four outputs,
individually set) (ATS305n)
0-2.5V, 0-5V, 0-10V, 0-20mA*
Digital outputs
High = open circuit
Low = open drain closure to 0V
No configuration required
Copy RSSI to an analogue output (ATI2) 0 (none) or number of output 1-4
Make one input PTT (transmit carrier
continuously when held at 0V) (ATS316)0 (none) or number of input 1-4
vnas the last digit of an AT command indicates the input or output number.
*Note: 0-20mA ports will typically be used in the range 4-20mA to interface with standard
current loop equipment.
See page 16 for information about configuring Alarms and Alerts.
Mode I Parameters
Spontaneous
Trigger Levels
(ATS312n)
If Mode I is used to transmit changes spontaneously, then to prevent
nuisance levels of traffic, the minimum change which will trigger a
report must be specified.
A digital input must change and remain for a dwell time. The dwell
time is the same as for alarms, and is part of the input configuration.
An analogue input must change by more than a specified amount
(the dead band) and stay outside it for a dwell time. This parameter
is set independently of any others.
Trigger Level parameters are set for each input individually.