Guralp Systems CD1.1 User Manual
CD1.1 Tools for
CMG-EAMs
and CMG-DCMs with
Platinum firmware
Operator's Guide
Part No. MAN-EAM-1100
Designed and manufactured by
Güralp Systems Limited
3 Midas House, Calleva Park
Aldermaston RG7 8EA
England
Proprietary Notice: The information in this
manual is proprietary to Güralp Systems Limited
and may not be copied or distributed outside the
approved recipient's organisation without the
approval of Güralp Systems Limited. Güralp
Systems Limited shall not be liable for technical
or editorial errors or omissions made herein, nor
for incidental or consequential damages resulting
from the furnishing, performance, or usage of this
material.
Issue C 2010-06-15
CD1.1 Tools for Platinum
Table of Contents
1 Introduction...........................................................................5
1.1 Platinum architecture.........................................................................5
1.2 CD1.1 architecture.............................................................................6
2 The CD1.1 modules.................................................................8
2.1 The CD1.1 multiplexor (data-mux-cd11)............................................8
2.1.1 Frame assembly time-outs..........................................................9
2.2 The GDI to CD1.1 converter (gdi2cd11)...........................................11
2.2.1 Channel Subframe Status Field.................................................12
2.3 The CD1.1 receiver (data-in-cd11)...................................................15
2.4 The CD1.1 sender (data-out-cd11)..................................................16
3 Typical configurations...........................................................18
3.1 Single seismic station......................................................................18
3.2 Central station of an array...............................................................19
3.3 Handling different frame lengths.....................................................19
3.4 Different frame lengths from one CMG-DM24..................................20
4 Using the Multiplexor............................................................ 21
4.1 Creating a new multiplexor instance...............................................21
4.2 Configuration options for the multiplexor........................................22
4.2.1 Configurable parameters in standard mode..............................22
4.2.2 Configurable parameters in expert mode..................................23
5 Using the GDI to CD1.1 converter...........................................25
5.1 Creating a new GDI to CD1.1 converter instance............................25
5.2 Configuration options for the converter...........................................26
5.2.1 Configurable parameters in standard mode..............................26
5.2.2 Configurable parameters in expert mode..................................31
6 Using the CD1.1 Receiver......................................................33
6.1 Creating a new CD1.1 receiver instance..........................................33
6.2 Configuration options for the receiver.............................................34
6.2.1 Configurable parameters in standard mode..............................34
6.2.2 Configurable parameters in expert mode..................................36
6.3 Operation notes...............................................................................37
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7 Using the CD1.1 Sender.........................................................38
7.1 Back-filling and retransmission........................................................38
7.2 Creating a new CD1.1 sender instance............................................39
7.3 Configuration options for the sender...............................................40
7.3.1 Configurable parameters in standard mode..............................40
7.3.2 Configurable parameters in expert mode..................................44
8 Frame database files.............................................................45
8.1 Managing database files..................................................................45
8.2 Examining database files.................................................................47
9 Logging and analysing..........................................................48
9.1 Web-based tools..............................................................................48
9.1.1 Multiplexer log analysis tool......................................................48
9.1.2 Receiver log analysis tool..........................................................51
9.1.3 Sender log analysis tool.............................................................52
9.2 Command-line tools.........................................................................56
9.2.1 cd11-backfilldb-tool...................................................................57
9.2.2 cd11-framedb-tool.....................................................................59
9.2.3 cd11-timedb-tool.......................................................................60
9.2.4 cd11-frame-analyser-tool..........................................................62
9.2.5 cd11-management-tool.............................................................64
10 Authentication Management................................................67
10.1 Process Overview...........................................................................67
10.2 Spyrus Lynks operation..................................................................68
10.2.1 Card initialisation.....................................................................68
10.2.2 Keypair generation..................................................................68
10.2.3 Certificate signing requests.....................................................69
10.3 CD1.1 operation.............................................................................69
10.3.1 cd11-spyrus-tool.sh.................................................................70
11 Configuring DM24s and CD24s.............................................72
11.1 SoH reporting.................................................................................72
11.2 Latency..........................................................................................73
12 Calibration Values...............................................................74
12.1 Seismic sensors (velocity)..............................................................75
12.2 Seismic sensors (acceleration)......................................................76
12.3 Acoustic or infrasound sensors......................................................77
12.4 Wind speed....................................................................................77
12.5 Wind direction................................................................................77
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12.6 Temperature..................................................................................78
13 Optional flash memory........................................................79
14 File reference.....................................................................80
14.1 Operation.......................................................................................80
14.2 Database........................................................................................80
14.3 Inter-process communication.........................................................81
14.4 Configuration.................................................................................81
14.5 Run Control....................................................................................82
14.6 Miscellaneous................................................................................83
15 Revision history..................................................................84
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1 Introduction
The Güralp CD1.1 tool suite for the Platinum firmware of CMGEAM, CMG-DCM and CMG-NAM hardware consists of four
modular components that can be used together to implement
either a single-station CD1.1 sender or a cross-array sender,
coalescing subframes from multiple stations into a single
outgoing data frame for the entire array.
When building an array, each individual element of the array is
actually a fully independent CD1.1 sender in its own right.
Supported features include fully-conformant status fields (State
of Health or SoH), flexible tamper line support, Canadian
compression and optional hardware authentication. Back-fill
capacity is limited only by the size of the fitted flash module or
disk array.
The CD1.1 tool suite runs in parallel to other programs, so it is
possible to use other data formats simultaneously.
1.1 Platinum architecture
Platinum firmware runs natively on CMG-EAMs and CMG-NAMs.
It can also be installed on the earlier CMG-DCM units. Platinum
firmware is based on the Linux operating system, which
provides a robust, familiar and flexible platform for the
protocol-handling and configuration software.
Seismic protocols are handled by a number of configurable
software modules, which run as user-space programs. They
can, on the whole, be stopped, reconfigured and started
independently of each other. The whole system is managed by
a flexible and extensible configuration interface which is
accessible in near-identical format from either the web
interface or a character-based terminal, connected either
serially or over a network.
The majority of the protocol-handling features of Platinum are
based on Güralp Data Interconnect, or GDI. The gdi-base
module serves as the central data interchange, accepting data
from a wide variety of input protocol-conversion modules,
buffering and re-ordering incoming data where necessary,
associating samples with their meta-data and providing data
via a consistent interface to the output protocol-conversion
modules.
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It is possible to use CD1.1 under Platinum without using GDI
but, if any data received in different formats are to be
converted to CD1.1, they will first be converted to GDI and
passed via the gdi-base module.
For pure CD1.1 implementations, it is neither efficient nor
necessary to convert to and from GDI, so a separate CD1.1
multiplexor module is provided. Incoming CD1.1 frames are
not passed to GDI, so it is not possible to convert them into
non-CD1.1 formats, such as SEEDlink.
1.2 CD1.1 architecture
The CD1.1 tool suite consists of four modules:
• The CD1.1 receiver (data-in-cd11), which receives
data in CD1.1. format from external CD1.1 data
producers (DPs);
• The GDI to CD1.1 converter (gdi2cd11), which receives
data from GDI and, thus, indirectly, from any other
source in any supported format;
• The CD1.1 multiplexer (data-mux-cd11), which accepts
and combines data from one or more instances of the
previous two modules; and
• The CD1.1 sender (data-out-cd11), which takes data
from a CD1.1 multiplexer instance and transmits them
in CD1.1 format to external CD1.1 data consumers
(DCs).
Any useful configuration will, therefore, use at least three of
these modules. It is possible to configure more than one
instance of any of these modules and these can be connected
together as necessary when building more complex
implementations.
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The diagram, above, shows a simple configuration using all four
CD1.1 modules. It is necessary to use either the CD1.1
Receiver (data-in-cd11) or the GDI to CD1.1 converter
(gdi2cd11) but not you do not need to use both.
The diagram also shows the subframe database which stores
all subframes passing through. These can then be used to
satisfy back-fill requirements and retransmission requests from
external receivers. This database can be located either in flash
RAM or on a hard drive, depending on considerations of storage
space and power consumption.
The data paths between modules are implemented using POSIX
local IPC sockets.
The following sections provide an introduction to how each
module works. Typical configurations will then be discussed,
followed by a detailed description of each module's
instantiation, configuration and use.
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2 The CD1.1 modules
This section of the manual will describe the function of each of
the four CD1.1 modules in detail. For precise configuration
instructions, please refer to sections 4 through 7.
2.1 The CD1.1 multiplexor (data-mux-cd11)
This is the central store-and-forward module for CD1.1
subframes. Every CD1.1 configuration requires at least one
CD1.1 multiplexor instance to be active. An instance of this
module must be configured before the configuration system
will allow any other CD1.1 modules to be instantiated.
CD1.1 subframes originating from either external CD1.1
sources (via data-in-cd11) or from non-CD1.1 sources (via
gdi2cd11) are transmitted to this module. The multiplexor
stores these subframes, either on disk or in flash RAM, and will
coalesces frames from multiple sources where this is
appropriate. It then forwards complete data frames onwards to
the output stage, data-out-cd11.
Subframes are stored briefly before they are assembled into
frames. There is a trade-off between the data latency - the
amount of time between a subframe's reception and its
transmission as part of a frame - and the overall framing
efficiency - the number of subframes that can be packed into a
single frame. A parametrised algorithm is used to allow the
operator to tune this to suit each application's specific
requirements - see section 2.1.1 on page 9 for more details.
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The multiplexor is responsible for responding to retransmission
requests arriving from external receivers via a data-out-cd11
instance. The subframe store is used to satisfy these requests.
An interactive logging tool is provided to allow the operator to
query and inspect the contents of the store.
One storage file is created per day. To limit the amount of
back-fill being stored, a directory cleaner task must be set up
to remove unwanted storage files.
2.1.1 Frame assembly time-outs
Two separate time-out parameters are used to control the
assembly of related subframes into frames: one for real-time
data and one for back-filled data.
In complex networks, data may arrive from a number of CD1.1
data producers (DPs) along diverse routes, each with different
transmission latencies. DPs may be added and removed at any
time and communications may be interrupted for short or long
periods. A dropped link or a decommissioned station should
not interrupt the flow of data from other stations. Because of
this, the frame assembly algorithm does not and, indeed,
cannot know how many subframes it should expect for any
given time-stamp. It is therefore necessary to use time-outs
when assembling subframes into frames.
As an example, let us consider a hypothetical array with three
remote sensor stations functioning as CD1.1 DPs, all of which
use ten-second subframes, and a central data consolidation
station. The transmission times of the three links to the central
station are, say, one, two and three seconds. The real-time
data time-out at the central station will be set to three seconds.
At some time, T0, each station begins assembling samples into
subframes and, at around T0 + 10 seconds, they all transmit
their completed subframes to the station. Each subframe is
labelled with the time-stamp of its first sample: T0.
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At T0 + 11 seconds, the first subframe arrives at the station.
The multiplexer inspects the time-stamp and, as it has not seen
any subframes labelled T0 before, it stores the subframe in a
new collection, labelled T0, and sets an alarm (specific to this
collection) for the current time (T0 + 11) plus the time-out - i.e.
T0 + 14 seconds.
At T0 + 12 seconds, the second subframe arrives at the
station. The multiplexer inspects the time-stamp and places
the subframe in the existing T0 collection. At T0 + 13 seconds,
the third subframe arrives and is treated identically. At this
point, the multiplexer does not know that it has received all the
subframes, so it carries on waiting.
At T0 + 14 seconds, the alarm for this collection fires and the
multiplexer assembles all the subframes from the T0 collection
into a frame and passes it to the data-out-cd11 module(s).
The collection is moved to the data store and is no longer
considered active.
Now consider the case where the third communication link is
interrupted for, say, five seconds, starting at T0 + 10. The first
and second subframes will arrive as before and, at T0 + 14
seconds, they will be assembled into a frame and transmitted.
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One second later, at T0 + 15 seconds, the link is restored and
the third subframe is transmitted. It will arrive at T0 + 18
seconds. The multiplexer inspects the time-stamp and, as it
has no longer has an active collection labelled T0, it stores the
subframe in a new collection, also labelled T0, and sets an
alarm (specific to this collection) for the current time (T0 + 18
seconds) plus the time-out - i.e. T0 + 21 seconds. No more
packets labelled T0 will arrive so, when the alarm fires, the lone
subframe will be wrapped up as a frame and transmitted on its
own.
If the time-out had been set to eight seconds, the delayed
subframe would have arrived in time to be sent along with the
other two: the packing efficiency would have been improved
but, as the completed frame would not have been transmitted
until T0 + 19 seconds, the overall latency would have
increased. The time-out should thus be adjusted to achieve the
desired trade-off between subframe packing efficiency and
overall data latency.
Where back-filled subframes are involved, it is assumed that
latency is of lesser concern - the data are already significantly
delayed - and packing efficiency is considered more important.
For this reason, although the algorithm is identical, a
separately configurable time-out is provided which only applies
to back-fill frames. It is expected that this time-out will
normally be set to a significantly higher value than the live
data time-out.
2.2 The GDI to CD1.1 converter (gdi2cd11)
This module is used to encode data from non-CD1.1 sources
into standards-compliant CD1.1 subframes. It should be used,
for example, when data from directly attached digitisers and
digital instruments is to be transmitted using CD1.1.
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The subframes contain a number of additional data beside the
samples:
• Channel meta-data is used to populate the “instrument
type” and “gain” fields
• The “channel status” field is populated using
information from the state-of-health data provided by
gdi-base, from the anti-tamper lines (and other digital
input/output fields) and from the internal temperature
and voltage monitoring subsystems.
• Optionally, a cryptographic signature generated by a
hardware engine (such as the Spyrus encryption card).
Operation of such hardware is discussed in chapter 10
on page 67.
The subframes can support any sample rate and can be of
various durations (in multiples of 10 seconds).
2.2.1 Channel Subframe Status Field
The gdi2cd11 module implements the first permitted status
field as defined with format value = 1 in the CTBTO standard
revision 0.2. There are several reserved bits and bytes in the
standard, and these can optionally be mapped to additional
details in the gdi2cd11 configuration (see section 6.2.1 on page
34).
The meaning of the bits is mapped as follows (counting from 1,
with 1 being the least significant bit and 8 the most):
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Byte(s) Bit(s) Description Mapping
2 1 Dead sensor channel Not used
2 Zeroed data Not used
3 Clipped Not used
4 Calibration underway Set when calibration is in
progress on associated
component
3 1 Equipment housing open Configurable tamper monitor
2 Digitiser open Configurable tamper monitor
3 Vault door opened Configurable tamper monitor
4 Authentication seal
broken
Configurable tamper monitor
5 Equipment moved Configurable tamper monitor
6–8 Future use Configurable tamper monitors
4 1 Clock diff. too large Set if clock difference
≥±1000µs (configurable)
2 GPS receiver off Set if ADC module reports no
communication from GPS, or
GPS power is off
3 GPS receiver unlocked Set if ADC module reports
clock is not phase locked to
GPS PPS signal
4 Analog input shorted Not used
5 Calibration loop back Not used
6–8 Future use Not used
5 1 Main power failure Configurable; set if voltage of
chosen line drops below
specified value
2 Backup power unstable Configurable; set if voltage of
chosen line drops below
specified value (independent
from main power failure bit)
3–8 Future use Not used
6 1–8 Undefined Configurable; 8-bit voltage,
temperature, power or
current reading #1
7 1–8 Undefined Configurable; 8-bit voltage,
temperature, power or
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Byte(s) Bit(s) Description Mapping
current reading #2
8 1–8 Undefined Configurable; 8-bit voltage,
temperature, power or
current reading #3
9–28 Time of last GPS
synchronisation
Most recent reported lock
from ADC module, invalid (<
year 2000) if never locked.
29–32 Clock differential in
microseconds
If clock is locked, this is the
measured difference between
the ADC's sample clock and
the GPS PPS line in µs. If
unlocked, it is an estimate
(magnitude, so always
positive) of the drift based on
the measured worst-case drift
of the ADC's crystal.
Bytes 6, 7 and 8 of the status field can optionally be used to
monitor line voltage, power or current flow, or temperature. As
there are only 8 bits available, the scales for the value are
complex and must be manually configured by the operator in
order to get the best range available. Values that are outside
what can be represented are clipped at 0 or 255 (not aliased).
The voltage scale allows a value between 5.0 and 30.5 to be
represented with 0.1 increments. To convert from the unsigned
byte value x to an analog value, use:
y=5.0x ×0.1
The power or temperature scale allows a value between -64
and 63.5 to be represented with 0.5 increments. Note CMGEAM modules measure incoming power as positive, and
outgoing power as negative. To convert from the signed byte
value x to an analog value, use:
y=x ×0.5
To convert from the unsigned byte value u to an analog value,
use:
u128 : y=u × 0.5
u≥ 128 y =u−256 × 0.5
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The current scale allows a value between -1.28 and 1.27 to be
represented with 0.01 increments. Note CMG-EAM modules
measure incoming current as positive, and outgoing current as
negative. To convert from the signed byte value x to an analog
value, use:
y=x ×0.01
To convert from the unsigned byte value u to an analog value,
use:
u128 : y=u × 0.01
u≥ 128 y =u−256 × 0.01
2.3 The CD1.1 receiver (data-in-cd11)
This module receives CD1.1 frames from external CD1.1
senders (DPs). It is typically used at an array data centre,
where it receives data frames from any CD1.1 senders in the
array; typically each array element or station will have its own
CD1.1 sender.
The receiver is fully standards-compliant, although it has no
support for validating incoming signatures.
The receiver can accept connections and data from multiple,
simultaneous, remote DPs. It correctly identifies and requests
re-transmission of missing data frames by issuing CD1.1
acknack frames.
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Note: Unlike other Platinum data reception modules, the CD1.1
receiver module does not currently alter or decode any
subframes it receives and it does not pass them to gdi-base:
they are passed on verbatim and only to the multiplexor
module.
2.4 The CD1.1 sender (data-out-cd11)
This module is a fully standards-compliant CD1.1 sender (DP).
It is responsible for:
• Receiving CD1.1 channel subframes from the
multiplexor;
• Assembling them into full CD1.1 frames;
• Transmitting them over a TCP network to a remote
receiver (DC);
• Handling retransmission requests originating from its
clients;
• Monitoring the transmission log to determine whether
any gaps have occurred (for example, due to restarting of the sender process) and, if so, transmitting
the missing packets (back-fill);
• Logging all transmissions to a “frame list” held on local
disk or Flash memory; and, optionally,
• Digitally signing the frames using an optional hardware
encryption engine (see chapter 10 on page 67).
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A CD1.1 sender module can only transmit to a single Data
Consumer (DC). If there is a requirement to support multiple
DCs, multiple sender module instances are needed. Each can
send a different set of subframes, if required.
Because the multiplexer supports multiple senders, it is more
efficient for the multiplexer to store transmitted frames, rather
than the sender. This avoids having to store the same frame
multiple times. However, because the frame numbering of
outgoing frames is connection specific, the multiplexer cannot
know these numbers and it stores frames by time-stamp,
rather than by frame number. The sender keeps track of which
frame is which by storing a database of frame numbers against
timestamps. This database is consulted when the sender
receives an acknack frame, so that it can request the correct
frame from the multiplexer by time-stamp.
It also handles back-fill over extended periods of outage by
recording which times the system was down, and requesting
the data once the link is established again. Back-fill order is
configurable: it can either be “first-in, first-out” (FIFO) or “lastin, first-out” (LIFO).
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3 Typical configurations
Some typical scenarios, with the associated module set-ups,
are shown in the following diagrams.
3.1 Single seismic station
In this scenario, one or more analogue sensors are digitised by
a CMG-DM24, the output from which is fed over a serial or
network link to a CMG-EAM. The data are passed to gdi-base
in the normal way and the gdi2cd11 module combines them
with state-of-health and other meta-data to form CD1.1
subframes. These are passed to the multiplexor, which
assembles them into frames for onward transmission by the
CD1.1 sender.
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3.2 Central station of an array
The second diagram illustrates a typical array scenario, where
the central CMG-EAM accepts full CD1.1 frames from each
element and coalesces them, outputting only a single station
frame.
3.3 Handling different frame lengths
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This diagram depicts the use of two gdi2cd11 converter
modules to handle subframes with different frame lengths.
The multiplexor combines them into a single CD1.1
transmission. Although all the data passes through the gdi-
base module, input filtering in the gdi2cd11 instances
separates them again so that each can be framed
appropriately.
3.4 Different frame lengths from one CMG-DM24
The diagram above shows another way to handle different
frame lengths. In this scenario, two sensors of different types
are connected to the same CMG-DM24 digitiser and their
outputs travel together as far as the gdi-base module. Two
separate gdi2cd11 modules are then used to implement the
different subframe durations, according to the sensor type.
The outputs from the converters are then recombined by the
multiplexer module and passed to a common sender.
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4 Using the Multiplexor
The multiplexor module has two main functions: Firstly, it acts
as an IPC connection point between the input and output
modules, allowing an arbitrary number of modules of either
type to be connected together; Secondly, it stores subframes
on disk, allowing them to be retrieved by output modules for
back-fill and retransmission purposes.
In most applications, only a single multiplexor instance is
required although, if you have two completely independent
data paths, it may make sense to use more than one
multiplexor. Note that each input and/or output module can
only ever be connected to a single multiplexor instance.
4.1 Creating a new multiplexor instance
In the web interface, select “Configuration -> Services” from
the left-hand menu or from the command line, run
gconfig
and then select “System services”.
Now choose “data-mux-cd11 -- CD1.1 multiplexor” to view a list
of configured multiplexor instances. You can choose to either
configure any existing instance (as described in the following
section) or select “Create new service instance” to create a
new one.
A form is displayed which allows you to set various parameters
for the instance. The default values are suitable for most
applications but each parameter is discussed in the following
section. After entering the desired configuration for the
instance, choose Submit.
This will create (if it is new) and configure the multiplexor
instance. If it is not already running, you can start it by using
“Control -> Services” on the web menu or by running
/etc/init.local/data-mux-cd11.0 start
from the command line.
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The zero after the period in the command name determines
which multiplexor instance is to be started, so the command to
start a second instance would be
/etc/init.local/data-mux-cd11.1 start
4.2 Configuration options for the multiplexor
There are two levels of configuration options available:
standard and expert. The configuration screen is first displayed
in standard mode but extra options can be displayed by
clicking the “Expert” button at the bottom of the form.
4.2.1 Configurable parameters in standard mode
The User description is an alternative, human-readable label
for this instance. It is used, for example, in log files. If you are
building a complex application with several multiplexers, you
should set this to something which describes the function of
this particular instance. In most cases, this can be left at the
default setting.
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The Enable check-box controls whether this instance is to be
automatically started each time the system boots or whether it
should be left to be started manually.
The Delete check-box, if ticked, will cause this instance to be
deleted when the form is submitted.
The Database directory field allows you to specify the path to
a directory where the subframes are stored. A directory
specified here should not be used for any other purposes and
should not be shared with any other data-mux-cd11 instances.
The default location, /var/lib/data-mux-cd11.n, where n is
the instance identifier, will be adequate in most applications.
Note that large files will accumulate in this directory so: (a) you
should ensure that you have sufficient space available to store
the expected amount of data; and (b) you should configure a
directory cleaner to remove unwanted files from this directory
(see Section 8.1 on page 45 for more details). This database
may be stored on additional flash memory, if fitted: See
Section 13 on page 79 for more details.
The Data frame transmission period field controls the realtime data time-out described in section 2.1.1 on page 9. It
should be set to achieve the desired trade-off between
subframe packing efficiency and data latency.
The Back-filled frame transmission period fulfils a similar
function with respect to back-filled data and is also described in
section 2.1.1 on page 9.
4.2.2 Configurable parameters in expert mode
Two additional parameters are configurable when in export
mode.
The Log file field allows a separate log-file to be maintained,
dedicated to this multiplexer instance. When left blank, the
standard syslog subsystem is used and, for most applications,
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this is adequate. For extremely complex set-ups or when
performing analysis for performance tuning, it may be useful to
segregate messages from this instance into a separate file.
Whether logging to syslog or to a dedicated file, the Log level
pull-down menu allows you to select the level of detail that will
be logged. The options are a subset of the standard syslog
levels: “Warnings”, “Important notices”, “Informational
messages” and “Debugging information”. Setting this field to
“Warnings” produces the least output and setting it to
“Debugging information” produces the most.
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5 Using the GDI to CD1.1 converter
This module is used to encode data from non-CD1.1 sources
into standards-compliant CD1.1 subframes. It should be used,
for example, when data from directly attached digitisers and
digital instruments is to be transmitted using CD1.1.
The converter maps incoming channel names to CD1.1 names,
which consist of three parts: station (5 characters), channel (3
characters) and location (2 characters), separated by periods.
A note in the CD1.1 standard states that the IMS receiving
software does not use the location field for anything.
5.1 Creating a new GDI to CD1.1 converter instance
In the web interface, select “Configuration -> Services” from
the left-hand menu or from the command line, run
gconfig
and then select “System services”.
Now choose “gdi2cd11 -- CD1.1 converter/subframe generator”
to view a list of configured converter instances. You can
choose to either configure any existing instance (as described
in the following section) or select “Create new service
instance” to create a new one.
A form is displayed which allows you to set various parameters
for the instance. Each parameter is discussed in the following
section. After entering the desired configuration for the
instance, choose Submit.
This will create (if it is new) and configure the converter
instance. If it is not already running, you can start it by using
“Control -> Services” on the web menu or by running
/etc/init.local/gdi2cd11.0 start
from the command line.
The zero after the period in the command name determines
which converter instance is to be started, so the command to
start a second instance would be
June 2010 25
CD1.1 Tools for Platinum
/etc/init.local/gdi2cd11.1 start
5.2 Configuration options for the converter
There are two levels of configuration options available:
standard and expert. The configuration screen is first displayed
in standard mode but extra options can be displayed by
clicking the “Expert” button at the bottom of the form.
5.2.1 Configurable parameters in standard mode
There are a large number of standard options that can be
configured for the GDI to CD1.1 converter, so the basic
configuration screen is shown here in sections.
The User description is an alternative, human-readable label
for this instance. It is used, for example, in log files. If you are
building a complex application with several converters, you
should set this to something which describes the function of
this particular instance. In most cases, this can be left at the
default setting.
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