manual may not in whole or in part be copied,
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the written consent of a duly authorized officer of
Radyne ComStream Corporation.
Radyne ComStream Corporation 3138 E. Elwood St. Phoenix, AZ 85034 (602) 437-9620 Fax: (602) 437-4811
Latest Software Revision Confirmation
When new features are added to Radyne ComStream Corporation equipment, the control
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Before creating any software based on the information contained in this document,
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to find out if the software revision for that piece of equipment is current and that no new
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The following are expressly not covered under warranty:
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Radyne ComStream Corporation will not make warranty adjustments for failures of products or parts which
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Including but not limited to warranties of merchantability and of fitness for particular purpose, use,
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normal use or are of limited life, such as but not limited to, bulbs, fuses, lamps, glassware, etc.
Radyne ComStream Corporation reserves the right to revise the foregoing list of what is covered
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Before a warranty repair can be accomplished, a Repair Authorization must be received. It is at this time
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Radyne ComStream Corporation
3138 E. Elwood St.
Phoenix, Arizona 85034 (USA)
ATTN: Customer Support
Phone: (602) 437-9620
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damage resulting from improper packing and handling, and for loss in transit, not withstanding any defect or
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ComStream Corporation has sole responsibility for determining the cause and nature of failure, and Radyne
ComStream Corporation’s determination with regard thereto shall be final.
TM065 – Rev. 3.3 iv
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem Record of Revisions
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
Installation and Operation Manual
TM065 – Record of Revisions
Radyne ComStream Corporation is constantly improving its products and therefore the
information in this document is subject to change without prior notice. Radyne ComStream
Corporation makes no warranty of any kind with regard to this material, Including but not limited to
the implied warranties of merchantability and fitness for a particular purpose. No responsibility for
any errors or omissions that may pertain to the material herein is assumed. Radyne ComStream
Corporation makes no commitment to update nor to keep current the information contained in this
document. Radyne ComStream Corporation assumes no responsibility for use of any circuitry
other than the circuitry employed in Radyne ComStream Corporation systems and equipment.
Revision
Level
1.0 7-18-97 Preliminary Release
2.0 3-1-99 Added IBS/IDR Update information; New Interfaces Section; Updated
3.0 3-15-01 Revised manual format.
3.1 3-11-02 Revised Section 4, and 5.6.16. Added new product features.
3.2 5-28-02 Revised Technical Manual
3.3 5-29-02 Revised opcodes and commands.
Date Reason for Change
Remote Spec.
TM065 - Rev. 3.3 v
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
This Page is Intentionally Left Blank
TM065 – Rev. 3.3 vi
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem Table of Contents
The Radyne Corporation DMD2401 and DMD2401L Satellite Modems (Figure 1-1) are
microprocessor-controlled Binary Phase Shift Keyed (BPSK), Quadrature Phase Shift Keyed
(QPSK), Offset Quadrature Phase Shift Keyed (OQPSK), or Trellis Coded 8 Phase Shift Keyed
(8PSK) Modulators/Demodulators. They are used as part of the transmitting and receiving ground
equipment in a satellite communications system. The modem is designed for service in an SCPC
system where two modems are set for continuous operation with each other.
Note: Unless specified, DMD2401 denotes both the DMD2401 and DMD2401L units.
This versatile equipment package combines unsurpassed performance with numerous userfriendly front panel programmable functions. The DMD2401 provides selectable functions for
Intelsat IBS/IDR, as well as closed networks. All of the configuration, monitor, and control
functions are available at the front panel. Operating parameters such as variable data rates, FEC
code rate, IF frequencies and IBS/IDR framing can be readily set and reconfigured from the front
panel by earth station operations personnel. Additionally, all functions can be accessed with a
terminal or personal computer via a serial link for complete remote monitor and control capability.
The DMD2401 operates at all standard IBS and IDR data rates up to 4.375 Mbps. Selection of
any data rate in closed network operation is provided over the range of 9.6 Kbps to 4.375 Mbps in
1 bps steps. The maximum symbol rate is 2.5 Msps, regardless of modulation type, FEC, code
rate or framing type.
The DMD2401 is designed to perform as both ends of a satellite Single Channel Per Carrier
(SCPC) link or as the VSAT remote site modem in a TDMA hub system in mesh or star topology
networks. The Modulator and Demodulator operate independently using BPSK, QPSK, OQPSK,
or 8PSK modulation in either SCPC or VSAT Modes.
The DMD2401 is also the ideal VSAT modem for use in a Point-to-Point Frame Relay Hybrid
Network. Other applications include FDMA, telephony, video conferencing, long-distance
learning, paging and newsgathering.
Refer to Table 1-1 for selection of any data rate that is provided over the following ranges:
Table 1-1. Data Rates
FEC 1/2 2/3 3/4 7/8
BPSK
QPSK
OQPSK
8PSK
The DMD2401 is programmable from the front panel. The program menu was specifically
designed for ease of use to quickly put the modem online and for any network changes. The
modem also can be monitored and controlled through the RS-485 or RS-232 serial control
channel.
The DMD2401 can track and acquire a carrier over a programmable range of ±1 kHz to ±42 kHz.
Acquisition times of less than 10 seconds are typical at data rates of 64 Kbps over a range of
± 25 kHz.
To facilitate link testing, the DMD2401 incorporates built-in ‘2047’ test pattern generators with
BER measurement capability. A user-selectable terrestrial and/or satellite loopback test capability
is also provided.
For applications requiring systems redundancy, multiple DMD2401 modems may be used with the
Radyne RCS11 1:1 Redundancy Switch or the RCS20 M:N (N < 9) Redundancy Switch. A full
range of industry-standard interfaces are available for the DMD2401, DMD2401L, and DMD2401
IBS/IDR. These include RS-232, V.35, RS-422/-449 and ITU G.703.
Available options for the DMD2401 includes a low data rate asynchronous serial overhead
channel for remote monitor and control. Additionally, a Sequential Codec is available for
applications requiring compatibility with existing systems.
Figure 1-1. DMD2401 Satellite Modem
1.1 DMD2401 Available Options
A wide range of options are available for the DMD2401 Satellite Modem. A brief description of
each follows:
1.1.1 Reed-Solomon Codec
The DMD2401 can be equipped with a Reed-Solomon outer codec with an interleaver as an
optional enhancement. The encoder and decoder are completely independent and meet IESS308/-309 Specifications. Once prepped, this option can be installed in the field by following an
upgrade procedure.
Note: Custom Reed-Solomon codes are also available.
1.1.2 Sequential Decoding
The DMD2401 can also be equipped with an optionally installed sequential decoder. The
DMD2401 must be prepped for this option in the factory. Once prepped, the option can be added
by installing a daughter card on an existing header. Sequential Encoding/Decoding can operate
with 1/2, 3/4, and 7/8 Rates up to data rates of 4.375 Mbps.
1.1.3 Asynchronous Overhead Channel
The DMD2401 can be equipped with optional asynchronous overhead channel capability. The
option can be added in the field by installing a single interface PC board. The overhead channel
is proportional to the data rate (Baud Rate is approximately 1/2000 of the Data Rate for Standard
IBS and up to a maximum of 19.2 Kbaud for IBS Async).
The DMD2401 may be customized for specific customer requirements. Most
modifications/customization can be accomplished by means of firmware/software modifications.
The following are examples of the types of customization available to the user:
1. Customized Data Rates.
2. Customized Scrambler/Descramblers.
3. Customized Overhead Framing Structures.
4. Customized Modulation Formats.
5. Customized Uses for Asynchronous Overhead Channel.
1.1.5 8PSK Modulation
The DMD2401 can be equipped with 8PSK Modulation capability as an add-on option. The 8PSK
Option can be added by installing one IC into an existing socket.
1.1.6 Analog AGC Voltage
The DMD2401 can be equipped at the factory to produce an analog voltage equivalent to its AGC
for use in antenna controllers.
1.1.7 Drop and Insert (D&I)
The DMD2401 can be equipped at the factory with D&I as an add-on enhancement. The D&I
Functions are completely independent and can be programmed for n x 64 blocks of either T1 or
E1 Data Streams.
1.1.8 Turbo Product Codec (TPC)
The DMD2401 can be equipped at the factory with TPC as an add-on option. The TPC Option is
a daughter card, which can be added by installing the card on modems with the required header.
TPC works with all installed modulations on the DMD2401 and functions throughout the Modem’s
symbol rate limits. TPC is used to enhance performance of the DMD2401 Modem
The DMD2401 can be installed within any standard 19-inch equipment cabinet or rack, and
requires 1 RU mounting space (1.75 inches) vertically and 21 inches of depth. Including cabling,
a minimum of 23-inches of rack depth is required. The rear panel is designed to have power
enter from the left and IF cabling enter from the right when viewed from the rear of the unit. Data
and control cabling can enter from either side although they are closer to the left. The unit can be
placed on a table or suitable surface if required.
There are no user-serviceable parts or configuration settings located inside the
DMD2401chassis. There is a potential shock hazard internally at the power supply
module. DO NOT open the DMD2401chassis under any circumstances.
Before initially applying power to the unit, it is a good idea to disconnect the transmit
output from the operating ground station equipment. This is especially true if the
current DMD2401 configuration settings are unknown, where incorrect settings could
disrupt existing communications traffic.
2.1 Unpacking
The DMD2401 Modulator was carefully packaged to avoid damage and should arrive complete
with the following items for proper installation:
1. DMD2401 Unit.
2. Power Cord, 6-foot with applicable AC connector.
3. Installation and Operation Manual.
2.2 Removal and Assembly
Carefully unpack the unit and ensure that all of the above items are in the carton. If the Prime AC
power available at the installation site requires a different power cord/AC connector, then
arrangements to receive the proper device will be necessary before proceeding with the
installation.
The DMD2401 Modulator is shipped fully assembled. It does not require removal of the covers for
any purpose in installation. The only replaceable assembly in the unit is the data interface and is
not intended to be accomplished in the field. Should the power cable AC connector be of the
wrong type for the installation, either the cable or the power connector end should be replaced.
The power supply itself is designed for universal application using from 100 to 240 VAC, 50 – 60
When mounted in an equipment rack, adequate ventilation must be provided. The ambient
temperature in the rack should be between 10° and 35° C, and held constant for best equipment
operation. The air available to the rack should be clean and relatively dry. The DMD2401 units
may be stacked one on top of the other up to a maximum of 10 consecutive units before providing
a 1 RU space for airflow.
Do not mount the DMD2401 in an unprotected outdoor location where there is direct contact with
rain, snow, wind or sun. The DMD2401 is designed for indoor applications only.
The only tools required for rack mounting the DMD2401 is a set of four rack mounting screws and
an appropriate screwdriver. Rack mount brackets are an integral part of the cast front bezel of the
unit and are not removable.
Shielded cables with the shield terminated to the conductive backshells are required in order to
meet EMC directives. Cables with insulation flammability ratings of 94 VO or better are required
in order to meet low voltage directives.
The following interface connections should be available at the mounting location as a minimum:
3. An RS-449 Data Interface Cable with a 37-Pin Male ‘D’ Sub-Connector.
2.4 Modulator Checkout
The following descriptions assume that the DMD2401 is installed in a suitable location with prime
AC power and supporting equipment available.
2.4.1 Initial Power-Up
Before initial powerup of the DMD2401, it is a good idea to disconnect the transmit output
from the operating ground station equipment. This is especially true if the current
modulator configuration settings are unknown, where incorrect settings could disrupt the
existing communications traffic. New units from the factory are normally shipped in a
default configuration which includes setting the transmit carrier off.
Turn the unit ‘ON’ by placing the rear panel switch (above the power entry connector) to the ‘ON’
position. Upon initial and subsequent power-ups, the DMD2401 microprocessor will test itself and
several of its components before beginning its main Monitor/Control program. These power-up
diagnostics show no results if successful. If a failure is detected, the Fault LED is illuminated.
The initial field checkout of the modem can be accomplished from the front panel or in the
Terminal Mode. The Terminal Mode has the advantage of providing full screen access to all of
the modem’s parameters, but requires a separate terminal or computer running a terminal
program. The unit is placed into terminal mode by setting two options via the front panel. The two
options are the Term Baud and Emulation settings found under the System M&C submenus.
A digital terrestrial interface supplies the modulator with a data stream. The data stream is
synchronized if the incoming stream is framed. The data is scrambled, and FEC is added. The
data is then convolutionally encoded, punctured, then constellation mapped. The resulting I&Q
symbols are digitally filtered. The data is then converted into an analog waveform and is vector
modulated onto an RF Carrier produced from the Transmit IF Synthesizer Circuitry.
3.1 DMD2401 Operation
A block diagram of the signal flow is shown in Figure 3-1 below. The modem is shown in a typical
application with customer data, Tx/Rx RF Equipment and an antenna.
Figure 3-1. Functional Block Diagram
3.2 Applications
Following are just a few representative forms of satellite communication links and networks in
which the DMD2401 modem may be used.
3.2.1 SCPC Point-to-Point Links
The most straightforward application for a satellite modem is to serve as the Data
Communications Equipment (DCE) for a point-to-point data link. When used in this mode, two
modems located at two different sites are tuned to complementary transmit and receive
frequencies. Each direction of the communications link may have the same or entirely different
transmission parameters. In this application, it is typical that the link is established and
maintained on a continuous basis, although a special “on demand” case is described later.
3.2.2 SCPC Point to Multi–Point Links in a Broadcast Application
A broadcast application might involve the necessity of sending continuous or intermittent data
from one source and “broadcasting” the information to many remote locations. For instance,
constant pricing information and updates may be sent by a central location to many store
locations. There may be minor return information from the remotes acknowledging receipt.
Another broadcast application could be transmitting background music from a central location to
many store sites. In this case, there would be no return path.
The topology of the network in both of these broadcast examples would typically be called a “Star”
network. As shown in Figure 3-2, the shape of the configuration is drawn with the central “Hub” as
the center of the star and the remotes as points of the star. In both cases the transmit frequency
and other parameters are shared by the receiver of all the remotes.
Figure 3-2. Star Network Configuration
3.2.3 DAMA (Demand Assigned Multiple Access)
Suppose that a telephone network with a virtual switch between modems carrying digitized voice
information is to be simulated. We might use a central computer to assign a pair of frequencies
for any conversation and send this connection information to the proper sites to set up the
connection. In this application, a new network configuration is usable. That is a “Mesh” network
where any of the voice modems at any site can be programmed to link with any other modem.
The resulting link diagram looks like a mesh of interconnects.
Since the frequencies can be assigned on demand, the network is then called “Demand Assigned,
Multiple Access,” or DAMA.
3.2.4 TDMA (Time Division Multiple Access) Remote Site Application
In a TDMA network, the central Hub continually transmits a stream of outbound data containing
information for multiple remote sites, while the remote sites transmit back to the Hub on a timed
basis. Each of these remotes is said to “burst” its information back on a specific frequency. This
may be the same inbound frequency for all sites. Each of the remotes is responsible for
accessing its own information from the outbound data stream by reading the address assigned to
specific parts of the data. The TDMA network usually looks like the Star network shown in
Figure 3-2.
The DMD2401 is specifically designed to be usable as the remote site modem of a TDMA network
when coupled with a proper “Burst” demodulator at the hub site.
The DMD2401 is shipped from the factory with preset factory defaults. Upon initial power-up, a
user check should be performed to verify the shipped modem configuration. Refer to Section 3,
Operation for the Modulator and Demodulator Front Panel Menu Screens to locate and verify the
following configuration settings are correct:
Note: Transmit (Tx) and Receive (Rx) Interface types are dependent upon the customer’s
order.
Standard DMD2401 Factory Configuration Settings
Modulator:
To lock up the modem, turn the carrier ON, enter ‘IF Loopback Enable,’ or connect a loopback
cable from J1 to J4 on the rear panel of the modem.
3.4 DMD2401 Automatic Uplink Power Control (AUPC Operation)
The DMD2401 modem has an optional built-in provision for Automatic Uplink Power Control
(AUPC). AUPC attempts to maintain a constant Eb/No at the receive end of an SCPC link. This is
especially useful when operating over a satellite at Ku-Band frequencies in locations with high
rainfall periods.
Note: An Asynchronous or IBS Interface is required for AUPC. Also, IBS (Async Framing
Mode MUST be selected to provide a channel for AUPC operation.
The IBS (Async Framer Data Mode provides a service channel between the two sites of a link
permitting the modem processors to send messages and get responses over this channel. AUPC
can be set to operate on either or both directions of a link but always requires a bi-directional
channel. Therefore, both the Modulator and Demodulator interface mode must be set to IBS
(Async for the AUPC menus to be visible and for the AUPC function to operate properly. The
AUPC functions and their descriptions are shown below:
The AUPC menus are located under the Modulator Menu as shown in Section 4.
AUPC ENABLE/DISABLE Enables/Disables the AUPC to function locally
AUPC Eb/No Desired Eb/N0 of remote modem
AUPC MIN LVL Sets minimum output power to be used
AUPC MAX LVL Sets maximum output power to be used
AUPC DEF LVL Sets default output power to be used
The basic AUPC operation is described as follows: Assume that the two modems, one at each
end of the link, are set to AUPC operation. Only one direction is discussed, but the same
functions could be occurring in both directions simultaneously. Modem “A” is transmitting to
modem “B” under normal conditions and modem “B” has a receive Eb/No of 7.5 dB. Modem “A”
has been set to an AUPC Eb/No on the front panel of 7.5 dB, and is currently outputting –15 dBm.
Next, it begins raining at location “B”, and the Eb/No drops to –7.0 then –6.8 dB. Modem “B” is
constantly sending update messages to “A” and reports the current Eb/No. When “A” sees the
drop in Eb/No, it slowly begins to raise the output power, and raises it again when it sees further
drops. As the rain increases in intensity, and the Eb/No decreases again, “A” continues to
increase its power level to compensate, and when the rain diminishes and quits, it lowers its
power level to compensate. The operation is therefore a feedback control loop with the added
complication of a significant time delay.
There are safeguards built into the AUPC system. First, the Modulator has two additional
parameters, which allow control of the maximum and minimum power output levels. Second, a
default power level is specified which takes precedence over the output power level during signal
loss or loss of AUPC channel communication. The default power level should normally be set to a
high enough level to reestablish communication regardless of rain fade. The other controls are
built into the operating control software to limit response times and detect adverse operating
conditions.
3.5 DMD2401 Asynchronous Overhead Operation
3.5.1 Asynchronous Framing/Multiplexer Capability
The Asynchronous Framing/Multiplexer is capable of multiplexing a relatively low-speed overhead
channel onto the terrestrial data stream resulting in a slightly higher combined or aggregate data
rate through the modem. The overhead channel is recovered at the far end. This added channel
is termed variously “An Overhead Channel”, ”Service Channel”, “Async Channel” or in IESS
terminology an “ES to ES Data Channel.” The basic frame structure used by the multiplexer is
specified in the IESS-309 standard, Page 60, Figure 10, resulting in a 16/15 aggregate to through
data ratio.
For Regular Async. (Standard IBS), the Baud Rate is approximately 1/2000 of the Data Rate
listed in the table below. For Enhanced Async. (IBS Async.), the Baud Rate is selectable, but
limited by the Data Rate. The maximum Baud Rate is 19,200 bps for IBS Async.
Two software-controlled modes are designed into the card to best utilize the available bits;
“Standard IBS” and “IBS (Async)”. The characteristics of the Channel Interface is also determined
by the standard or Async mode.
The Async Channel can be set under software-control to either RS-232 or RS-485 mode. The pin
assignments for both modes are shown in Table 1. The “RS-485” setting controls the output into
tri-state when the modem is not transmitting data, allowing multiple modem outputs to be
connected together.
In the first or “Normal” mode, all bit assignments are per the IBS standard. The bits of Overhead
Housekeeping byte 32 are implemented as shown below:
Bit 1
ES to ES Data
Channel
This bit is routed directly to the ES to ES Data
Channel. Its data rate is 1/512th of the aggregate rate
(0r 1/480th of the through terrestrial data rate, and is
normally used to super-sample an asynchronous data
channel.
Bit 2
Bit 3
Bit 4
Bits 5 and 6
Bits 7 and 8
The ratio of the through terrestrial data channel rate to the aggregate rate is 15/16.
The standard transmit and receive channels of the ES to ES data channel in standard IBS mode
are raw channels operating at the specific bit rate as controlled by the data channel rate, without
buffering. In addition, no clocks are provided with this channel. Since it would be rare that the
data rate provided was exactly that required for a standard rate device, the only method of
communicating using this channel is to allow it to super-sample the user data.
Frame Alignment Part of the Frame Alignment word.
Backward Alarm Transmit and Receive with main processor to activate
main alarm/LED
Multiframe Message As per IBS
Spare Not currently utilized
Encryption Utilization Not currently utilized
3.7 Asynchronous Multiplexer Mode
Since many of the frame bits in the standard IBS mode are not used, an “Enhanced” multiplexer
mode has been implemented that can be engaged under software control. Since this mode
changes the use of many of the framed non-data bits, this mode is only usable when the
DMD2401 is at both ends of a link. In this mode, the overhead signaling bytes 16 and 48 can be
used to implement a significantly higher speed ES to ES Data Channel under software control.
When implemented, this rate is 16 times that of the normal IBS standard, or 1/30th of the
terrestrial data rate (1/32nd of the aggregate rate).
Note: The IBS Async mode MUST be selected for true Asynchronous channel operation to
be available.
3.8 ESC Backward Alarms
When running in IDR Mode and if the modem has the ESC Option, there will be four Backward
Alarms available for use by the earth stations at each end of the link (both ends must have the
ESC option). These alarms are accessed via the ESC ALARMS Port. The four alarms are
controlled by four relays, each having a normally open, normally closed, and a common
connection. The common connections of these relays (referred to as Backward Alarm Inputs) can
be connected to whichever system on the earth station that the user wishes to trigger the
backward alarm. When ground is applied to the common (input) connection of one of these
relays, that relay and associated backward alarm will then be in a “no fault” state. When the
ground is removed, the relay and the associated Tx Backward Alarm will toggle to the faulted
state. When in the faulted state, the receive end of the link will receive that backward alarm that
is initiated at the transmit end of the link.
The user can connect whichever systems on the earth stations that they desire to these Backward
Alarms Relays as long as they will supply ground to the Backward Alarm Relay Input in the “no
fault” condition and the ground will be removed in the “faulted” condition.
For example: the user could connect the Demod Summary Fault of the modem to the Backward
Alarm 1 Input, so that if the demod went into Major Alarm (such as a Carrier Loss), Backward
Alarm 1 would be transmitted to the receive end of the link. At the receive end, it would show up
as Rx Backward 1 (Receive Backward Alarm 1).
3.8.1 To Disable the ESC Backward Alarms
If the ESC ALARMS Port will not be used and the Backward Alarm Indications are to be disabled,
connect the following pins of the ESC ALARMS Port:
Connect Pins 1, 10, 11, 22 and 23 (connect all together). Pin 1 is ground and Pins 10, 11, 22, and
23 are the inputs of Backward Alarms 1 through 4. By connecting these four pins to ground
(Pin 1) the Backward Alarms will be disabled and indicate “PASS” for BK1 through BK4.
3.9 IDR or IBS/D&I Configuration Instructions
Note: Newer Modems are Front Panel Configurable (disregard Sections 3.9.1 and 3.9.2).
To check; from the Front Panel (Section 4.2.7), go to System Menu, Firmware Rev. Menu,
‘DaughterCPLD’, and check for F04230 Revision C or above, or F04821.
3.9.1 IDR Configuration (Older Modems)
1. In this configuration, J17 on the back panel will be used as the ESC Port.
2. Attach the 10 Pin Ribbon Cable from J17 on the Back Panel to J3 on the AS/3760
Interface Card.
3. Remove Jumpers R38 and R40 located on the AS/3771 Daughter Card.
4. Cycle power on the unit.
3.9.2 IBS/D&I Configuration (Older Modems)
1. In this configuration, J17 on the back panel will be used as the ES-ES Communications
Port.
2. Attach the 10 Pin Ribbon Cable from J17 on the Back Panel to J11 on the AS/3771
Daughter Card.
3. Install Jumpers R38 and R40 located on the AS/3771 Daughter Card.
4. Cycle power on the unit.
3.10 Configuring the DMD2401 for Drop and Insert
Several dependencies exist when configuring the modem for Drop and Insert (D&I). The following
paragraphs explain these dependencies and provide the user with the information required to
ensure smooth transition into Drop & Insert and to minimize the potential impact of these
dependencies.
6. Select the Terrestrial Frame Source (applicable to Insert only).
7. Use the SatCh TS edit capability to define the desired mapping of Satellite Channels to
Terrestrial Slots.
8. Copy the appropriate Edit Map to the Active Map.
3.10.1 Interface Type
Interface Type affects the terrestrial framing and data rates used by the Drop & Insert function in
the following ways:
1. When a T1 interface type is selected, the terrestrial framing options will only reflect the
valid T1 framing selections of:
T1-D4 (D4 framing, no Robbed Bit Signaling)
T1-ESF (ESF framing, no RBS)
T1-D4-S (D4 framing with Robbed Bit Signaling)
T1-ESF-S (ESF framing with RBS)
2. When an E1 interface type is selected, the terrestrial framing options will only reflect the
valid E1 framing selections of:
PCM-30 (Channel Associated Signaling)
PCM-30C (CAS with CRC checking)
PCM-31 (Common Channel Signaling)
PCM-31C (CCS with CRC checking)
3. When a T1 interface type is selected, attempting to change the data rate to 1920000 will
result in the error message ‘DATA RATE OUT OF BOUNDS’. If an E1 interface type is
selected, a data rate entry of 1920000 is valid and will be allowed.
The operational mode of the modem often determines which additional menus and displays are
available for use by the operator. The D&I mode-specific menus will not be displayed unless the
operational mode of the modem is set to D&I. Therefore, the next step in configuring the modem
should be to set the operational mode to D&I. At this point, the D&I specific menus in the
Interface section will become available and will remain available until the operational mode of the
modem is changed to something other than D&I. When the operational mode is changed to
something other than D&I, the D&I specific menus will automatically disappear.
Mode affects the Drop & Insert function by affecting the Data Rate in the following manner:
1. In Closed Net mode, any valid IDR, IBS, or Drop & Insert data rate may be entered.
2. In Drop & Insert Mode, only valid D&I data rates may be entered.
The entry of an invalid rate will result in the error message ‘DATA RATE OUT OF BOUNDS.’
3.10.3 Data Rate
Data Rate also affects the Drop and Insert function in the following ways:
1. It determines the number of Satellite Channels that will be displayed in the Edit Maps.
2. It contributes to the operational mode selection process. Trying to change the operational
mode to Drop & Insert when a data rate is not set to a valid D&I rate will result in the error
message ‘DATA RATE OUT OF BOUNDS.’ The mode change will not be allowed.
3. Once Drop & Insert mode has been selected, trying to change the data rate to something
other than another valid D&I data rate will result in the error message ‘DATA RATE OUT
OF BOUNDS.’ The change will not be allowed.
The Mod Data Rate should be set according to the number of timeslots to be dropped, and the
Demod Data Rate should be set according to the number of timeslots to be inserted. The
following table gives the allowable D&I data rates based on the number of slots (n) to be dropped
or inserted.
3.10.4 Terrestrial Framing - Drop Mode/Insert Mode
The Drop Mode selection and the Insert Mode selection identify the terrestrial data-framing
format. As previously mentioned, their selection is influenced by the mod and demod interface
types. In turn, the selection of the terrestrial framing formats influences the satellite channel to
terrestrial timeslot mappings in the following manner:
1. The selection of T1-D4, T1-ESF, or T1-D4-S, or T1-ESF-S type terrestrial framing format
limits the terrestrial timeslots to values from 1-24.
2. The selection of PCM-30 or PCM-30C type terrestrial framing limits the terrestrial
timeslots to values from 1-15, 17-31. In these modes, terrestrial timeslot 16 is reserved
for ABCD signaling and may not be dropped or inserted.
3. The selection of PCM-31 or PCM-31C type terrestrial framing limits the terrestrial
timeslots to values from 1-31.
Therefore, the terrestrial framing format should be identified via the Drop Mode and Insert Mode
entries prior to editing the Drop or Insert satellite channel to terrestrial timeslot maps.
3.10.4.1 Insert Terrestrial Frame Source
The insert terrestrial frame source selection tells the modem where the insert terrestrial frame is
coming from. External means the terrestrial frame is to be input via the Insert Data In port.
Internal means that the modem needs to generate the terrestrial frame and that all non-inserted
timeslots need to be filled with the appropriate idle code based upon the terrestrial framing (T1 or
E1). In addition, the selection of the insert terrestrial frame source also influences the Buffer
Clock selection in the following manner:
When the insert terrestrial frame source selection is set to External, the received satellite data will
be clocked out of the Doppler buffer based upon the clock recovered from the insert data input.
Therefore, the Buffer Clock selection will automatically be set to External and cannot be modified.
When the insert terrestrial frame source selection is set to Internal, the operator needs to specify
how data should be clocked out of the Doppler buffer. In this case, the operator will be able to
select either SCTE, SCT, or RX SAT as the source for the Buffer Clock. Therefore, the insert
terrestrial frame source selection should be made prior to attempting to change the Buffer Clock.
In most instances, the insert terrestrial frame source selection will be set to External and the
Buffer Clock will automatically be set to External.
3.10.5 Alarms
The following alarms are unique to Drop & Insert and vary based on the terrestrial framing:
Alarms
Modem Alarms
Active Alarms
Minor Tx
Drop Alarms
FrmLock – Indicates Terrestrial Frame lock on the Send Data Port.
Valid in all framing modes
MFrmLck – Indicates Terrestrial Multiframe lock on the Send Data Port.
Valid in PCM-30, PCM-30C
CRCLock – Indicates valid CRC received via the Send Data Port.
Valid in PCM-31C, PCM-30C
SigData – Indicates valid signaling data received via the Send Data Port.
Valid in PCM-30, PCM-30C
Minor Rx
Insert Alarms
FrmLock – Indicates Terrestrial Frame lock on the Receive Data Port.
Valid in all framing modes
MFrmLck – Indicates Terrestrial Multiframe lock on the Receive Data Port.
Valid in PCM-30, PCM-30C
There are also additional Backward Alarms available in Drop & Insert Mode
Alarms
Modem Alarms
Backward Alarms
Prompt – This is the prompt maintenance alarm output by the modem
Service – This is the deferred service alarm output by the modem
TerBack – Indicates whether or not a terrestrial backward alarm is being received
SatBack – Indicates whether or not a satellite backward alarm is being received which
would be caused by the demod losing lock at the other end of the link
Force TerBck – Allows the operator to force the terrestrial backward alarm output to
On, Off, or Normal for testing purposes.
Force SatBck – Allows the operator to force the satellite backward alarm
The following displays under Interface D&I Setup ( both Tx and Rx ), are editing displays only:
SATCh TS
Enter to Edit
Any changes made in these displays are made on the screen, but are not entered into the
modem. Once these menus are configured, the Mapping Menu must be used to actually enter
the settings into the modem.
Example :
For a modem w/ Drop & Insert enabled at a data rate of 256 (with timeslots assigned 1-1, 2-2,
etc.). At a data rate of 256, the modem will allow 4 channels to assign timeslots to. Under the Tx
Menu, assign the timeslots that are to be used to the 4 channels. CH1 is assigned to TS1
(Timeslot #1), CH2 to TS 2, CH3 to TS3 and CH4 to TS4, <ENTER> must be depressed after
assigning each individual TS. Once the timeslots are assigned to the channels, use the Left or
Right Arrow Key to scroll to the Mapping Menu. This menu will appear in the following way:
Map Copy
******* *******
Note: The ******* will be one of several words, just look for the “Map Copy” display).
This is the menu where the channel assignments are actually entered into the modem. To do
this, perform the following steps:
For the Transmit Side:
1. Push <ENTER> to get the flashing cursor.
2. Use the Up Arrow Key to make the left portion of the display read “TX EDIT”.
3. Use the Right or Left Arrow Keys to switch the flashing cursor to the right portion of the
display.
4. Use the Up or Down Arrow Key to make the right hand portion read “TX ACTIVE”.
5. The mapping display should now look like this:
Map Copy
TX EDIT > TX ACTIVE
6. Push <ENTER> to enter this command. This tells the modem to configure to the settings
that were assigned in the Channel/Timeslot display.
1. With Rx Side Channels configured as follows: CH1 to TS1, CH2 to TS2, CH3 to TS3 and
CH4 to TS4.
2. After the timeslots are assigned properly, scroll to the Mapping Menu and use the above
procedure to enter the settings into the modem.
3. Set the display to read:
Map Copy
RX EDIT > RX ACTIVE
4. Press <ENTER> to enter the settings into the modem.
To View the current Timeslot Assignment:
1. If there is a question of the channels not being entered properly, the Mapping Menu may
be used to see how the channels/timeslots are configured in the modem.
2. Use <ENTER> and the Arrow Keys to make the mapping menu read (for the Tx Side):
Map Copy
TX ACTIVE > TX EDIT
3. Press <ENTER>. The modem has now copied the current Tx Settings to the Tx
Channel/Timeslot Display.
4. For the Rx Side:
Map Copy
RX ACTIVE > RX EDIT
5. Press <ENTER>. The modem has now copied the current Rx Settings to the Rx
Channel/Timeslot display ).
Note: It is not mandatory to assign timeslots in sequential order, although the lowest
timeslot must be entered in the lowest channel. For example: timeslots may be assigned
1-2, 2-5, etc. but not 1-5, 2-2.
3.12 Loopbacks
3.12.1 Terrestrial Loopback
Terrestrial Loopbacks provides the following data loopback on the interface card:
Tx Loopback – Terrestrial TX data after passing through the line interface is looped back
to the Rx data line drivers (refer to Figure 3-3).
Rx Loopback – The Rx data received by the satellite is looped back through the interface
for retransmission to the satellite providing a far end loopback (refer to Figure 3-4).
Tx/Rx Loopback – Provides both of the above loopbacks simultaneously (refer to
Figure 3-5).
Baseband Loopback provides the following data loopback on the baseband (or framing card) and
allows testing of the terrestrial interface of the modem:
Note: On the DMD2401, a framing card is required to properly use any of the baseband
loopback functionality.
Tx BB Loopback – Terrestrial TX data after passing through the line interface and onto
the baseband framing unit is looped back to the Rx data line drivers of the interface (refer
to Figure 3-6).
Rx BB Loopback – The Rx Data received by the satellite is passed through the interface
and looped back through baseband framing unit, then sent back through the interface for
retransmission to the satellite providing a far end loopback (refer to Figure 3-7).
Tx/Rx BB Loopback – Provides both of the above loopbacks simultaneously (refer to
Figure 3-8).
3.12.3 IF Loopback
IF Loopback loops back the modulated IF Signal from the modulator to the demodulator (refer to
Figure 3-9).
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Section 4 – User Interfaces
4.0 User Interfaces
There are three user interfaces available for the DMD2401. These are:
1. Front Panel
2. Remote Port
3. Terminal
4.1 Front Panel User Interface
The front panel of the DMD2401 allows for complete control and monitor of all DMD2401
parameters and functions via a keypad, LCD display and status LEDs.
The front panel layout is shown in Figure 4-1, showing the location and labeling of the front panel.
The front panel is divided into three functional areas: the LCD Display, the Keypad, and the LED
Indicators, each described below in Table 4-1.
Figure 4-1. DMD2401 Front Panel
Table 4-1.
Item Number Description Function
1 LCD Front Panel Display Displays DMD2401 Operating parameters
and Configuration data
2 Cursor Control Arrows Controls the up, down, right and left motion
of the cursor in the LCD Display window
3 Numeric Keypad Allows entry of numeric data and Clear and
Enter function keys
4 Front Panel LED Indicators See Paragraph 4.1.2 below for an itemized
description of these LEDs
4.1.1 Front Panel LCD Display
The front panel display is a 2 line by 16-character LCD display. The display is lighted and the
brightness can be set to increase when the front panel is currently in use. The LCD display
automatically dims after a period of inactivity. The display has two distinct areas showing current
information. The upper area shows the current parameter being monitored, such as ‘Frequency’
or ‘Data Rate’. The lower line shows the current value of that parameter. The LCD display is a
single entry window into the large matrix of parameters that can be monitored and set from the
front panel.
TM065 - Rev. 3.3 4-1
User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
4.1.2 Front Panel LED Indicators
Eight LEDs on the DMD2401 front panel (Refer to Table 4-2) indicate the status of the
DMD2401’s operation. The LED colors maintain a consistent meaning. Green signifies that the
indication is appropriate for normal operation, Yellow means that there is a condition not proper
for normal operation, and Red indicates a fault condition that will result in lost communications.
Table 4-2.
LED Color Function
Modem LED Indicators
Power Green Indicates that the unit is turned on.
Fault Red Indicates a hardware fault for the unit.
Event Yellow Indicates that a condition or event has occurred that the
modem has stored in memory. The events may be viewed
from the Front Panel or in the Terminal Mode.
Remote Green Indicates that the unit is set to respond to the remote control
input.
Modulator LED Indicators
Transmit On Green Indicates that the Transmit Output is currently active.
Major Alarm Red Indicates that the Transmit Direction has failed, losing traffic.
Minor Alarm Yellow Indicates that a warning condition exists.
Test Mode Yellow Indicates that the modulator is involved in a current Test
Mode activity.
Demodulator LED Indicators
Signal Lock Green Indicates that the receiver locked to an incoming signal,
including FEC Sync.
Major Alarm Red Indicates that the Receive Direction has failed, losing traffic.
Minor Alarm Yellow Indicates that a Receive Warning Condition exists.
Test Mode Yellow Indicates that the receiver is involved in a current Test Mode
activity.
4.1.3 Front Panel Keypad
The front panel keypad consists of two areas: a 10-key numeric entry with 2 additional keys for
the ‘Enter’ and ‘Clear’ function. The second area is a set of ‘Arrow’ or ‘Cursor’ keys (n), (p), (o),
(m), used to navigate the parameter currently being monitored or controlled. Table 4-3 describes
the key functions available at the front panel.
4-2 TM065 – Rev. 3.3
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
4.1.4 Parameter Setup
The four arrow keys (n), (p), (o), (m), to the right of the LCD display are used to navigate the
menu tree and select the parameter to be set. After arriving at a parameter that needs to be
modified, depress <ENTER>. The first space of the modifiable parameter highlights (blinks) and
is ready for a new parameter to be entered. After entering the new parameter using the keypad
(Refer to Figure 4-2), depress <ENTER> to lock in the new parameter. If a change needs to be
made prior to pressing <ENTER>, depress <CLEAR> and the display defaults back to the
original parameter. Depress <ENTER> again and re-enter the new parameters followed by
<ENTER>.
Following a valid input, the DMD2401 will place the new setting into the nonvolatile EEPROM
making it available immediately and available the next time the unit is powered-up.’
Table 4-3.
Edit Mode Key Functions (Front Panel Only)
Parameter
Type
Fixed Point
Decimal
Unsigned
Hexadecimal
Enumerated N/A Previous
Date/ Time Changes
IP Address Changes
Text Strings Changes
0 – 9
Changes
Digit
Changes
Digit
Digit
Digit
Character
Toggles ±
(If Signed)
Increments
Digit Value
Value in
List
N/A N/A Moves
Increments
Digit Value
Increments
Character
Value
Toggles ±
(If Signed)
Decrement
s Digit
Value
Next Value
in List
Decrement
s Digit
Value
Decrement
s Character
Value
Moves
Cursor 1
Position
Left
Moves
Cursor 1
Position
Left
N/A N/A N/A N/A
Cursor 1
Position
Left
Moves
Cursor 1
Position
Left
Moves
Cursor 1
Position
Left
‘Clear’ &
Moves
Cursor 1
Position
Right
Moves
Cursor 1
Position
Right
Moves
Cursor 1
Position
Right
Moves
Cursor 1
Position
Right
Moves
Cursor 1
Position
Right
N/A N/A
N/A N/A
N/A N/A
N/A N/A
Clears to
Left of
Cursor
Inclusive
‘Clear’ &
Clears to
Right of
Cursor
Inclusive
Figure 4-2. Entering New Parameters
TM065 - Rev. 3.3 4-3
User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
4.2 Front Panel Control Screen Menus
The DMD2401 Front Panel Control Screens are broken down into sections under several Main
Menus.
4.2.1 Main Menus
Modulator
Demodulator
Interface
Monitor
Alarms
System
Test
4.2.2 Modulator Menu Options and Parameters
Mod Mode: {IDR, IBS, D&I, Closed Net}
Used with IDR, or IBS Interface Only.Sets a number of parameters within the modem to meet
a set specification. The purpose is to eliminate
keystrokes and potential compatibility problems.
Additionally, data rates not covered by the given mode of
operation will not be allowed. If the mode of operation is
selected after the data rate has been entered, then the
data rate must be compatible with the desired mode of
operation or the mode will not be allowed. The following
parameters are set for the given mode of operation:
IDR Mode:
(IESS-309)
For Data Rates: 1.544, 2.048 (Mbps)
Framing Type: 96 Kbps (IDR)
Scrambler Type: V.35 - IESS
Spectrum Mask: Intelsat
IBS Mode:
(IESS-308)
Data Rates: 1.544, 2.048 (Mbps), n x 64
Framing Type: 1/15 (IBS)
Scrambler Type: IBS
Spectrum Mask: Intelsat
4-4 TM065 – Rev. 3.3
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
D&I Mode:
(IESS-308)
Data Rates: n x 64
Framing Type: 1/15 (IBS)
Scrambler Type: IBS
Spectrum Mask: Intelsat
Closed Net:
All possible combinations allowed
Mod IF (menu):
Freq (MHz): {50 – 90 MHz, 100 – 180 MHz, or 950 – 1750 MHz} Allows the user to enter the Modulator IF Frequency in 1
Hz increments.
Power: {-5 to –30 dBm}Allows the user to enter the Transmitter Power Level.
Carrier:{On, Off, Auto, Vsat, RTS,}Allows the user to select the Carrier Type. Refer to
Appendix B for further information.
Spectrum Inv:{Normal, Inverted} Allows the user to invert the direction of rotation for PSK
Modulation. Normal meets the IESS Specification.
Modulation:{BPSK, OQPSK, QPSK, 8PSK}Allows the user to select the modulation type.
Impedance:{75 , 50 }Allows the user to select the output impedance.
Mod Data (menu):
Data Rate: {Refer to Table 1-1 for Data Rates}
Allows the user to set the Data Rate in Bps steps. Conv Enc: {VIT 1/2, VIT 3/4, VIT 7/8, Optional SEQ 1/2, Optional
SEQ 3/4, Optional SEQ 7/8, Optional TRE 2/3}
Allows the user to select the Tx Code Rate and Type.
Diff Code:{On, Off}
Enables or disables the Differential Encoder.
Scrmbl Sel:{None, V.35-IESS, V.35 CCITT, V.35-EF, IBS, Reed-
Allows the user to enable or disable the Reed-Solomon
Encoder.
ModRS Codes: {Any valid n/k values can be entered (refer to
Appendix A)}
Displays the currently used n, and k Reed-Solomon
Codes. In Closed Net Mode, custom RS Codes may be
selected.
ModRS Depth:{4, 8}Displays the currently used Reed-Solomon Interleaver
Depth. In Closed Net Mode, a depth of 4 or 8 may be
selected.
4.2.3 Demodulator Menu Options and Parameters
Demod Mode: {IDR, IBS, D&I, Closed Net}
Used with IDR, or IBS Interface Only.Sets a number of parameters within the modem to meet
a set specification. The purpose is to eliminate
keystrokes and potential compatibility problems.
Additionally, data rates not covered by the given mode of
operation will not be allowed. If the mode of operation is
selected after the data rate has been entered, then the
data rate must be compatible with the desired mode of
operation or the mode will not be allowed. The following
parameters are set for the given mode of operation:
Terrestrial Loopback is performed at the Terrestrial
Interface.
Tx Terr – Sends Tx Terrestrial Data to Rx Data Out.
Rx Terr – (Distant Loop) Sends received satellite data to
the Modulator for transmission to the distant end.
Tx/Rx Terr – Enables both.
Baseband Loopback is performed at the interface
between the Baseband Processor Card and the
Modem Card. This ensures Framer/Deframer
integrity.
Tx BB – Sends Tx Data to the Receive Input to the BB
Card.
Rx BB – Sends Rx Data from the Modem Card to the Tx
Data Input to the Modem Card.
Tx/Rx BB – Enables both.
IF Loopback loops the IF Output of the Modulator to the
IF Input of the Demodulator.
Carrier: {CW, Dual, Offset, Normal}
CW - Causes the Modulator to output pure carrier.
Dual – Causes a double sideband output.
Offset – Causes a single sideband output.
Normal – Causes the Modulator to output normal
modulation.
TxForce Alrm: {No, Yes}
Allows a Major Tx Alarm to be forced (for testing
purposes, etc.).
RxForce Alrm: {No, Yes}
Allows a Major Rx Alarm to be forced (for testing
purposes, etc.).
Remote Port: {Normal, Test}
Test sends a constantly looping data packet through the
Remote Port that displays “Testing…”.
LED Test: {Normal, Test}
Allows the user to test Front Panel LED function.
4.3 Terminal Mode Control
The DMD2401 Terminal Mode Control allows the use of an external terminal or computer to
monitor and control the modem from a full screen interactive presentation operated by the modem
itself. No external software is required other than VT100 terminal emulation software (e.g.
“Procomm” for a computer when used as a terminal. The control port is normally used as an RS–
232 connection to the terminal device. The RS-232 operating parameters can be set using the
modem front panel and stored in EEPROM for future use.
TM065 - Rev. 3.3 4-23
User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
4.3.1 Modem Terminal Mode Control
The modem can be interactively monitored and controlled in the Terminal mode, with a full screen
presentation of current settings and status. Programming is accomplished by selecting the item to
be modified and pressing the terminal key of the option number. For example, to change the
transmit data rate, enter ‘33’ at the terminal. The modem will respond by presenting the options
available and requesting input. Two types of input may be requested. If the input is multiple
choice, the desired choice is selected by pressing the ‘Space’ key. When the desired option is
displayed, press the ‘Enter’ key to select that option. The other possible input type requires a
numerical input (such as entering a frequency or data rate. This type of input is followed by
pressing the ‘Enter’ or carriage return key. An input can be aborted at any time by pressing the
‘ESC’ key. Invalid input keys cause an error message to be displayed on the terminal.
The Terminal Control Mode supports serial baud rates of 300, 1200, 2400, 4800, 9600, 19200,
38400, 57600, and 115200. The connection must be set for 8 data bits, 1 stop bit and no parity
(8,N,1. Three terminal emulations are supported: VT100, WYSE 50, and ADDS-VP.
$ is used for setting the screen when the terminal is used is used for the first time or the nonvolatile memory gets reset.
4.3.2 Modem Setup for Terminal Mode
Terminal mode communications and protocol is set from the front panel control by setting the
“Control Mode” parameter to “Terminal”, and then setting the “Modem Port,” “Term Baud” and
“Emulation” parameters as desired. Then a terminal is connected to Connector J5 on the Back
Panel. All operating software for the terminal mode is contained within the DMD2401 modem
internal control software.
A “break” signal on the communications line, pressing “ESC” on the terminal or Power On of the
modem will initiate full screen terminal mode printing and redraw the full screen. The terminal
mode displays the present status of all user parameters controlled and read by the processor, and
offers a menu allowing change to any controlled parameter.
The Terminal Mode uses eight “Screens,” each of which have the basic contents of the three
modem monitor and control areas as set in the front panel matrix columns. This screen is used
for setting the parameters of the Modulator, Demodulator, Event, Alarm, Latched Alarm, Drop
Controls, Insert Controls, and Interface Areas.
Representations of the terminal screens are shown in Figures 4-3 through 4-22. These screens
may differ from the exact screens displayed due to changes in software and the presence of
options in the modem hardware. For instance, the presence of a Drop and Insert will result in
added options available on the screens, or additional screens to be available.
Note: Values contained within the [ ] Brackets are optional values based upon factory
settings. They will only appear when AGC Voltage (Section 4.2.5) is configured.
4-24 TM065 – Rev. 3.3
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
33.Ext Ref Fq:10.000000 53.Tx Clock Pol:Auto 73.BufClk Sel :RX SAT
54.SCT Source :Internal 74.Buff Clk Pol:Normal
55.Tx Framing :None 75.Rx Framing :None
42.Tx Ckt ID :
43.Rx Ckt ID :
Enter Selection Number:
Figure 4-22. Closed Net/RS-422/V.35/RS-232 Interface Control Terminal Screen
4.4 Remote Port User Interface
The Remote Port of the DMD2401 allows for complete control and monitor functions via an
RS-485 or RS-232 Front Panel Configurable Serial Interface.
Control and status messages are conveyed between the DMD2401 and the subsidiary modems
and the host computer using packetized message blocks in accordance with a proprietary
communications specification. This communication is handled by the Radyne Link Level Protocol
(RLLP), which serves as a protocol ‘wrapper’ for the M&C data.
Complete information on monitor and control software is contained in the following sections.
4.4.1 Protocol Structure
The Communications Specification (COMMSPEC) defines the interaction of computer resident
Monitor and Control software used in satellite earth station equipment such as Modems,
Redundancy Switches, Multiplexers, and other ancillary support gear. Communication is bidirectional, and is normally established on one or more full-duplex 9600-baud multi-drop control
buses that conform to EIA Standard RS-485. If a single device is placed on a single control bus,
then the control bus may conform to EIA Standard RS-232.
Each piece of earth station equipment on a control bus has a unique physical address, which is
assigned during station setup/configuration or prior to shipment. Valid decimal addresses on one
control bus range from 032 to 255 for a total of up to 224 devices per bus. Address 255 of each
control bus is usually reserved for the M&C computer.
4.4.2 Protocol Wrapper
The Radyne COMMSPEC is byte-oriented, with the Least Significant Bit (LSB) issued first. Each
data byte is conveyed as mark/space information with one mark comprising the stop data. When
the last byte of data is transmitted, a hold comprises one steady mark (the last stop bit). To begin
or resume data transfer, a space (00h) substitutes this mark. This handling scheme is controlled
by the hardware and is transparent to the user. A pictorial representation of the data and its
surrounding overhead may be shown as follows:
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User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
S1 S2 B
B1 B2 B3 B4 B5 B6 B7 S1S2,
0
etc.
The stop bit, S1 is a mark. Data flow remains in a hold mode until S1 is replaced by a space. If
S1 is followed by a space, the space character is considered a start (ST) and not part of the actual
data (B0 - B 7).
The above byte-oriented protocol is standard for UART based serial communication ports such as
Workstation or Personal Computer (PC) COM ports. COM ports should be configured for 8 data
bits, no parity, and one stop bit. For example, for 9600-baud operation, COM ports should be
configured as:
9600, 8, N, 1
The COMMSPEC developed for use with the Radyne Link Level Protocol (RLLP) organizes the
actual monitor and control data within a shell, or ‘protocol wrapper’, that surrounds the data. The
format and structure of the COMMSPEC message exchanges are described herein. Decimal
numbers have no suffix; hexadecimal numbers end with a lower case h suffix and binary values
have a lower case b suffix. Thus, 22 = 16h = 000010110b. The principal elements of a data
frame, in order of occurrence, are summarized as follows:
<SYN> - the message format header character, or ASCII sync character, that defines the
beginning of a message. The <SYN> character value is always 16h (1 Byte).
<BYTE COUNT> - the Byte Count is the number of bytes in the <DATA> field (two bytes).
<SOURCE ID> - the Source Identifier defines the multi-drop address origin. Note that all nodes
on a given control bus have a unique address that must be defined (1 Byte).
<DESTINATION ID> - The Destination Identifier serves as a pointer to the multi-drop destination
device that indicates where the message is to be sent (1 Byte).
<FRAME SEQUENCE NUMBER> -The FSN is a tag with a value from 0 through 255 that is sent
with each message. It assures sequential information framing and correct equipment
acknowledgment and data transfers (1 Byte).
<OPCODE> - The Operation Code field contains a number that identifies the message type
associated with the data that follows it. Equipment under MCS control recognizes this code via
firmware identification and subsequently steers the DATA accordingly to perform a specific
function or series of functions. Acknowledgment and error codes are returned in this field
(two bytes).
<...DATA...> - The Data field contains the binary data bytes associated with the
<OPCODE>. The number of data bytes in this field is indicated by the <BYTE COUNT> value.
<CHECKSUM> - The checksum is the modulo 256 sum of all preceding message bytes,
excluding the <SYN> character (1 Byte). The checksum determines the presence or absence of
errors within the message. In a message block with the following parameters, the checksurn is
computed as shown in Table 4-4 below.
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Since the only concern is the modulo 256 (modulo 1 00h) equivalent (values that can be
represented by a single 8-bit byte), the checksum is 05h.
For a decimal checksum calculation, the equivalent values for each information field are:
2 + 240 + 42 + 9 + 3 + 223 + 254 = 773;
773/256 = 3 with a remainder of 5.
This remainder is the checksum for the frame.
5 (decimal) = 05h = 0101b = <CHECKSUM>
4.4.3 Frame Description and Bus Handshaking
In a Monitor and Control environment, every message frame on a control bus port executes as a
packet in a loop beginning with a wait-for-SYN-character mode. The remaining message format
header information is then loaded, either by the M&C computer or by a subordinate piece of
equipment (such as the DMD2401) requesting access to the bus. Data is processed in
accordance with the OPCODE, and the checksum for the frame is calculated. If the anticipated
checksum does not match then a checksum error response is returned to the message frame
originator. The entire message frame is discarded and the wait-for-SYN mode goes back into
effect. If the OPCODE resides within a command message, it defines the class of action that
denotes an instruction that is specific to the device type, and is a prefix to the DATA field if data is
required. If the OPCODE resides within a query message packet, then it defines the query code,
and can serve as a prefix to query code DATA.
The Frame Sequence Number (FSN) is included in every message packet, and increments
sequentially. When the M&C computer or bus-linked equipment initiates a message, it assigns
the FSN as a tag for error control and handshaking. A different FSN is produced for each new
message from the FSN originator to a specific device on the control bus. If a command packet is
sent and not received at its intended destination, then an appropriate response message is not
received by the packet originator. The original command packet is then re-transmitted with the
same FSN. If the repeated message is received correctly at this point, it is considered a new
message and is executed and acknowledged as such.
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If the command packet is received at its intended destination but the response message
(acknowledgment) is lost, then the message originator (usually the M&C computer) re-transmits
the original command packet with the same FSN. The destination device detects the same FSN
and recognizes that the message is a duplicate, so the associated commands within the packet
are not executed a second time. However, the response packet is again sent back to the source
as an acknowledgment in order to preclude undesired multiple executions of the same command.
To reiterate, valid equipment responses to a message require the FSN tag in the command
packet. This serves as part of the handshake/acknowledge routine. If a valid response message
is absent, then the command is re-transmitted with the same FSN. For a repeat of the same
command involving iterative processes (such as increasing or decreasing the transmit power level
of a DMD2401 modulator), the FSN is incremented after each message packet. When the FSN
value reaches 255, it overflows and begins again at zero. The FSN tag is a powerful tool that
assures sequential information framing, and is especially useful where commands require more
than one message packet.
The full handshake/acknowledgment involves a reversal of source and destination ID codes in the
next message frame, followed by a response code in the <OPCODE> field of the message
packet from the equipment under control.
If a command packet is sent and not received at its intended destination, a timeout condition can
occur because the packet originator does not receive a response message. On receiving devices
slaved to an M&C computer, the timeout delay parameters may be programmed into the
equipment in accordance with site requirements by Radyne ComStream, Inc. prior to shipment,
or altered by qualified personnel. The FSN handshake routines must account for timeout delays
and be able to introduce them as well.
4.4.4 Global Response Operational Codes
In acknowledgment (response) packets, the operational code <OPCODE> field of the message
packet is set to 0 by the receiving devices when the message intended for the device is evaluated
as valid. The device that receives the valid message then exchanges the <SOURCE ID> with
the <DESTINATION ID>, sets the <OPCODE> to zero in order to indicate that a good message
was received, and returns the packet to the originator. This “GOOD MESSAGE” opcode
is one of nine global responses. Global response opcodes are common responses, issued to the
M&C computer or to another device, that can originate from and are interpreted by all Radyne
equipment in the same manner. These are summarized as follows (all opcode values are
expressed in decimal form):
Table 4-5. Response Opcodes
Response Opcode Description Opcode
Good Message 00h
Bad Parameter FFh
Bad Opcode FEh
Bad Checksum FDh
Command Not Allowed in LOCAL Mode FCh
Command Not Allowed in AUTO Mode FBh
Bad Destination FAh
Unable to Process Command F9h
Packet Too Long F8h
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
The following response error codes are specific to the DMD2401:
When properly implemented, the physical and logical devices and ID addressing scheme of the
COMMSPEC normally precludes message packet contention on the control bus. The importance
of designating unique IDs for each device during station configuration cannot be overemphasized.
One pitfall, which is often overlooked, concerns multi-drop override IDs. All too often, multiple
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
devices of the same type are assigned in a direct-linked (“single-thread”) configuration accessible
to the M&C computer directly. For example, if two DMD2401 Modems with different addresses
(DESTINATION IDs) are linked to the same control bus at the same hierarchical level, both will
attempt to respond to the M&C computer when the computer generates a multi-drop override ID
of 22. If their actual setup parameters, status, or internal timing differs, they will both attempt to
respond to the override simultaneously with different information or asynchronously in their
respective message packets and response packets, causing a collision on the serial control bus.
To preclude control bus data contention, different IDs must always be assigned to the equipment.
If two or more devices are configured for direct-linked operation, then the M&C computer and all
other devices configured in the same manner must be programmed to inhibit broadcast of the
corresponding multi-drop override ID.
The multi-drop override ID is always accepted by devices of the same type on a common control
bus, independent of the actual DESTINATION ID. These override IDs with the exception of
“BROADCAST” are responded to by all directly linked devices of the same type causing
contention on the bus. The “BROADCAST” ID, on the other hand, is accepted by all equipment
but none of them returns a response packet to the remote M&C.
The following multi-drop override IDs are device-type specific, with the exception of
“BROADCAST”. These are summarized below with ID values expressed in decimal notation:
Directly-Addressed Equipment Multi-Drop Override ID
Broadcast (all directly-linked devices) 00
DMD-3000/4000, 4500 or 5000 Mod Section, DMD15 01
DMD-3000/4000, 4500 or 5000 Demod Section, DMD15 02
RCU-340 1:1 Switch 03
RCS-780 1:N Switch 04
RMUX-340 Cross-Connect Multiplexer 05
CDS-780 Clock Distribution System 06
SOM-340 Second Order Multiplexer 07
DMD-4500/5000 Modulator Section 08
DMD-4500/5000 Demodulator Section 09
RCU-5000 M:N Switch 10
DMD15 Modulator 20
DMD15 Demodulator 21
DMD15 Modem 22
DVB3000 Video Demodulator 23
RCS20 M:N Switch 24
RCS10 M:N Switch 25
RCS11 1:1 Switch 26
DMD2401 Modem 27
Unused 28-31
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User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
Note that multi-drop override IDs 01 or 02 can be used interchangeably to broadcast a message
to a DMD3000/4000 modem, or to a DMD4500/5000, or to a DMD15 modem. Radyne
ComStream Corporation recommends that the multi-drop override IDs be issued only during
system configuration as a bus test tool by experienced programmers, and that they not be
included in run-time software. It is also advantageous to consider the use of multiple bus systems
where warranted by a moderate to large equipment complement. Therefore, if a DMD2401 is
queried for its equipment type identifier, it will return a “27”.
4.4.6 Software Compatibility
The DMD2401 RLLP is not software-compatible with the
following previous Radyne products: RCU5000 and
DMD4500. These products may not occupy the same
bus while using this protocol as equipment malfunction
and loss of data may occur.
When Radyne equipment is queried for information (Query Mod, Query Demod, etc.) it responds
by sending back two blocks of data; a non-volatile section (parameters that can be modified by the
user) and a volatile section (status information). It also returns a count value that indicates how
large the non-volatile section is. This count is used by M&C developers to index into the start of
the volatile section.
When new features are added to Radyne equipment, the control parameters are appended to the
end of the non-volatile section, and status of the features, if any, are added at the end of the
volatile section. If a remote M&C queries two pieces of Radyne equipment with different software
revisions, they might respond with two different sized packets. The remote M&C MUST make use
of the non-volatile count value to index to the start of the volatile section. If the remote M&C is not
aware of the newly added features to the Radyne product, it should disregard the parameters at
the end of the non-volatile section and index to the start of the volatile section.
If packets are handled in this fashion, there will also be backward-compatibility between Radyne
equipment and M&C systems. Remote M&C systems need not be modified every time a feature
is added unless the user needs access to that feature.
4.4.7 Flow Control and Task Processing
The original packet sender (the M&C computer) relies on accurate timeout information with regard
to each piece of equipment under its control. This provides for efficient bus communication
without unnecessary handshake overhead timing. One critical value is designated the InterFrame Space (FS). The Inter-Frame Space provides a period of time in which the packet receiver
and medium (control bus and M&C computer interface) fully recover from the packet
transmission/reception process and the receiver is ready to accept a new message. The
programmed value of the Inter-Frame Space should be greater than the sum of the “turnaround
time” and the round-trip (sender/receiver/bus) propagation time, including handshake overhead.
The term “turnaround time” refers to the amount of time required for a receiver to be re-enabled
and ready to receive a packet after having just received a packet. In flow control programming,
the Inter-Frame Space may be determined empirically in accord with the system configuration, or
calculated based on established maximum equipment task processing times.
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Each piece of supported equipment on the control bus executes a Radyne Link Level Task
(RLLT) in accordance with its internal hardware and fixed program structure. In a flow control
example, the RLLT issues an internal “message in” system call to invoke an I/0 wait condition that
persists until the task receives a command from the M&C computer. The RLLT has the option of
setting a timeout on the incoming message. Thus, if the equipment does not receive an
information/command packet within a given time period, the associated RLLT exits the I/0 wait
state and takes appropriate action.
Radyne equipment is logically linked to the control bus via an Internal I/O Processing Task (IOPT)
to handle frame sequencing, error checking, and handshaking. The IOPT is essentially a link
between the equipment RLLT and the control bus. Each time the M&C computer sends a
message packet, the IOPT receives the message and performs error checking. If errors are
absent, the IOPT passes the message to the equipment’s RLLT. If the IOPT detects errors, it
appends error messages to the packet. Whenever an error occurs, the IOPT notes it and
discards the message; but it keeps track of the incoming packet. Once the packet is complete,
the IOPT conveys the appropriate message to the RLLT and invokes an I/0 wait state (wait for
next <SYN> character).
If the RLLT receives the packetized message from the sender before it times out, it checks for any
error messages appended by the IOPT. In the absence of errors, the RLLT processes the
received command sent via the transmitted packet and issues a “message out” system call to
ultimately acknowledge the received packet. This call generates the response packet conveyed
to the sender. If the IOPT sensed errors in the received packet and an RLLT timeout has not
occurred, the RLLT causes the equipment to issue the appropriate error message(s) in the
pending equipment response frame.
To maintain frame synchronization, the IOPT keeps track of error-laden packets and packets
intended for other equipment for the duration of each received packet. Once the packet is
complete, the IOPT invokes an I/0 wait state and searches for the next <SYN> character.
4.4.8 RLLP Summary
The RLLP is a simple send-and-wait protocol that automatically re-transmits a packet when an
error is detected, or when an acknowledgment (response) packet is absent.
During transmission, the protocol wrapper surrounds the actual data to form information packets.
Each transmitted packet is subject to time out and frame sequence control parameters, after
which the packet sender waits for the receiver to convey its response. Once a receiver verifies
that a packet sent to it is in the correct sequence relative to the previously received packet, it
computes a local checksum on all information within the packet excluding the <SYN> character
and the <CHECKSUM> fields. If this checksum matches the packet <CHECKSUM>, the
receiver processes the packet and responds to the packet sender with a valid response
(acknowledgment) packet. If the checksum values do not match, the receiver replies with a
negative acknowledgment (NAK) in its response frame.
The response packet is therefore either an acknowledgment that the message was received
correctly, or some form of a packetized NAK frame. If the sender receives a valid
acknowledgment (response) packet from the receiver, the <FSN> increments and the next
packet is transmitted as required by the sender. However, if a NAK response packet is returned,
the sender re-transmits the original information packet with the same embedded <FSN>.
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User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
If an acknowledgment (response) packet or a NAK packet is lost, corrupted, or not issued due to
an error and is thereby not returned to the sender, the sender re-transmits the original information
packet; but with the same <FSN>. When the intended receiver detects a duplicate packet, the
packet is acknowledged with a response packet and internally discarded to preclude undesired
repetitive executions. If the M&C computer sends a command packet and the corresponding
response packet is lost due to a system or internal error, the computer times out and re-transmits
the same command packet with the same <FSN> to the same receiver and waits once again for
an acknowledgment or a NAK packet.
To reiterate, the format of the message block is shown in Table B-4, Link Level Protocol Message
Block.
Table 4-6. Link Level Protocol Message Block
SYNC COUNT SRC
ADDR
The RLLP Remote Port Packet structure is as follows:
<SYNC> Message format header character that defines the beginning of a
message. The <SYNC> character value is always 0x16. (1 byte)
<COUNT> Number of bytes in the <DATA> field. (two bytes)
<SOURCE ADDR> Identifies the address of the equipment from where the message
originated. (1 byte)
<DEST ADDR> Identifies the address of the equipment where the message is to be sent.
(1 byte)
<FSN> Frame sequence number ensures correct packet acknowledgment and
data transfers. (1 byte)
<OPCODE> This byte identifies the message type associated with the information data.
The equipment processes the data according to the value in this field.
Return error codes and acknowledgment are also included in this field.
(two bytes)
<...DATA...> Information data. The number of data bytes in this field is indicated by the
<BYTE COUNT> value.
<CHECKSUM> The modulo 256 sum of all preceding message bytes excluding the
<SYNC> character. (1 byte)
DEST
ADDR
FSN OP
CODE
DATA
BYTES
CHECKSUM
4.4.9 DMD2401 Opcode Command Set
The DMD2401 Opcode Command Set is listed below, separated by commands that control the
modulator only, the demodulator only, or the entire module.
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
4.4.10 Modulator Command Set
Command Opcode
Query Mod All
2400h
Query Mod Latched Alarms 2405h
Query Mod Current Alarms 2408h
Query Mod Status 240Bh
Query Mod RTS Level 2433h
Command Mod All 2601h
Command Mod Frequency 2602h
Command Mod Data Rate 2604h
Command Mod Modulation Type 2606h
Command Mod Convolutional Encoder 2607h
Command Mod Differential Encoder 2608h
Command Mod Carrier Control 2609h
Command Mod Carrier Selection 260Ah
Command Mod Clock Control 260Bh
Command Mod Clock Polarity 260Ch
Command Mod Drop Mode 260Eh
Command Mod Output Level 260Fh
Command Mod Reed-Solomon Encoder 2610h
Command Mod Spectrum 2611h
Command Mod Operating Mode 2612h
Command Mod Scrambler Control 2613h
Command Mod Scrambler Type 2614h
Command Module Ext Ref Source 2616h
Command Mod Terrestrial Loopback 2617h
Command Mod Baseband Loopback 2618h
Command Mod Mode 2619h
Command Mod External EXC Clock 261Ah
Command Mod Ext Ref Frequency 261Bh
Command Mod Data Invert 2623h
Command Mod SCT Source 260Dh
Command Mod Async TERR Interface 2626h
Command Mod CTS Mode and Polarity 2631h
Command Mod CTS Level 2632h
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User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
Command Mod Carrier Delay 2637h
4.4.11 Demodulator Command Set
Command Opcode
Query Demodulator All 2401h
Query Demod Latched Alarms 2406h
Query Demod Current Alarms 2409h
Query Demod Status 240Ch
Query Demod Eb/No, Input Level, Raw BER, Corrected
BER, and Frequency Offset, AGC Voltage
Query Demod Lock Status 2437h
Command Demod All 2A00h
Command Demod Frequency 2A01h
Command Demod Data Rate 2A02h
Command Demod Sweep Boundary 2A04h
Command Demod Demodulation Type 2A07h
Command Demod Convolutional Decoder 2A08h
Command Demod Differential Decoder 2A09h
Command Demod Reed-Solomon 2A0Ah
Command Demod Mode 2A0Bh
Command Demod Descrambler 2A0Dh
Command Demod Descrambler Type 2A0Eh
Command Demod Spectrum 2A0Fh
Command Demod Buffer Clock 2A11h
Command Demod Buffer Clock Polarity 2A12h
240Dh
Command Demod Insert Mode 2A13h
Command Demod Operating Mode 2A17h
Command Demod BER Measure Period 2A1Ah
Command Demod Terrestrial Loopback 2A1Ch
Command Demod Baseband Loopback 2A1Dh
Command Demod IF Loopback 2A1Eh
Command Demod Center Buffer 2A20h
Command Demod Buffer Size Time/Bytes 2A31h
Command Demod Async TERR Int 2A2Eh
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
4.4.12 Module Command Set
RLLP Command Opcode
Query Module Identification 2403h
Query Module Current Alarms 240Ah
Query Module Time 240Eh
Query Module Date 240Fh
Query Module Time and Date 2410h
Query Module Options 2431h
Command Module Control Mode 2600h
Command Drop & Insert Map Copy 2C00h
Command Drop & Insert Map 2C01h
Command Module Clear Latched Alarms 2C03h
Command Module Set Time 2C04h
Command Module Set Date 2C05h
Command Module Set Time and Date 2C06h
Command Module Soft Reset 2C07h
Command Module Default Configuration 2C30h
4.4.13 Detailed Command Descriptions
4.4.13.1 DMD2401 Modulator
Opcode: <2400h> Query a Modulator’s Configuration and Status
Query Response
<1> Number of
Nonvol bytes
See Paragraph B.6. This is the number of configuration
bytes and is an offset to the start of the status block.
Configuration Bytes
<4>
<3>
<4>
<4>
<1>
Frequency
Reserved
Data Rate
EXC Clock
Modulation Type
Unsigned Binary Value in Hz
Ignore
Unsigned Binary Value in BPS
Unsigned Binary Value in Hz
0 = QPSK, 1 = BPSK, 2 = 8PSK, 4 = OQPSK
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User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<2>
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<1>
Convolutional
Encoder
Reed-Solomon
Reed-Solomon N
Reed-Solomon K
Reed-Solomon T
RS Interleaver
Depth
Scrambler
Control
Scrambler Type
Transmit Power
Level
Differential
Encoder
Carrier Control
Carrier Selection
Spectrum
Operating Mode
Clock Control
Clock Polarity
SCT Source
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Common Alarm 1
<1>
<1>
<1>
<24>
<1>
<1>
<1>
<1>
<1>
<1>
Alarm 1 Mask
Major Alarms
Alarm 2 Mask
Minor Alarms
Mask
Tx Circuit ID
Tx Terrestrial
Loopback
Tx Baseband
Loopback
Reserved
Reserved
Data Invert
Framing
Bit 0 = Transmit Processor Fault
Bit 1 = Transmit Output Power Level Fault
Bit 2 = Transmit Oversample PLL Lock Fault
Bit 3 = Transmit Composite Clock PLL Lock Fault
Bit 4 = IF Synthesizer Lock Fault
Bit 5 = Transmit FPGA Configuration Fault
Bit 6 = Transmit Forced Alarm
Bit 7 = External Reference PLL Lock Fault
(0 = Mask, 1 = Allow)
Bit 0 = Terrestrial Clock Activity Detect Fault
Bit 1 = Internal Clock Activity Detect Fault
Bit 2 = Tx Sat Clock Activity Detect Fault
Bit 3 = Tx Data Activity Detect Fault
Bit 4 = Tx Data AIS Detect Fault
Bit 5 = Transmit EXT BNC Clock Activity Detect Fault
Bit 6 = Transmit Reed-Solomon Fault
Bit 7 = Tx BUC Fault, LBST only
(0 = Mask, 1 = Allow)
Bit 0 = -12 V Alarm
Bit 1 = +12 V Alarm
Bit 2 = +5 V Alarm
Bit 3 = Interface FPGA
Bit 4 = Temperature
Bit 5 = Battery Fault
Bit 6 = RAM/ROM Fault
Bit 7 = Spare
(0 = Mask, 1 = Allow)
24 ASCII Characters
0 = Disabled, 1 = Enabled
0 = Disabled, 1 = Enabled
Ignore
Ignore
0 = Normal, 1 = Invert
Note: The following byte applies only if an
Asynchronous, IDR or IBS Interface is installed. If not,
ignore.
Note: The following byte applies to all DMD2401 modems,
regardless of interface type.
0 = Normal, 1 = Swapped
Note: The following nine bytes apply only if an
Asynchronous Interface Card or IBS Interface Card is
installed, and the AUPC option is also installed. If not, set
to zero.
Note: AUPC minimum power level < AUPC default power
level < AUPC max. power level.
0 = Disabled, 1 = Enabled
Unsigned Binary (1 Decimal Point Implied)
Signed Value, –50 to –300 (–5.0 to –30 dBm), Implied Decimal
Point
Signed Value, –50 to –300 (–5.0 to –30 dBm), Implied Decimal
Point
Signed Value, –50 to –300 (–5.0 to –30 dBm), Implied Decimal
Point
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DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<2>
Daughter Card
Fault Mask
Transmit Mode
Transmit IDR
Overhead Mode
IDR Backward
Alarm Mask
IDR Force
Backward Alarm
1
IDR Force
Backward Alarm
2
IDR Force
Backward Alarm
3
IDR Force
Backward Alarm
4
Interface Type
Transmit ESC
Audio #1 Volume
interface card is installed. If not, ignore.
0 = Mask, 1 = Allow
0 = Closed Net Mode
1 = IDR Mode
2 = IBS Mode
3 = Drop & Insert Mode
Note: The following 11 bytes apply only if an IDR or IBS
interface card is installed, and the transmit mode
parameter is set to IDR Mode. If an IDR or IBS interface
card is not installed, ignore. If an IDR or IBS interface
card is installed, but the transmit mode parameter is not
set to IDR mode, these bytes can be set to any valid
values, but will be ignored.
0 = Voice, 1 = 64 Kbit Data
Bit 0 = IDR Backward Alarm 1
Bit 1 = IDR Backward Alarm 2
Bit 2 = IDR Backward Alarm 3
Bit 3 = IDR Backward Alarm 4
Bits 4 - 7 = Spare
(0 = Mask, 1 = Allow)
0 = Force Alarm Always ON
1 = Force Alarm Always OFF
2 = Normal Operation
0 = Force Alarm Always ON
1 = Force Alarm Always OFF
2 = Normal Operation
0 = Force Alarm Always ON
1 = Force Alarm Always OFF
2 = Normal Operation
0 = Force Alarm Always ON
1 = Force Alarm Always OFF
2 = Normal Operation
Mapping of Satellite Channels to dropped Terrestrial Timeslots
Bit 0 = Terrestrial Frame Lock Fault (all modes)
Bit 1 = Terrestrial Multiframe Lock Fault (PCM-30 and
PCM-30C only)
Bit 2 = Terrestrial CRC Lock Fault (PCM-30C and PCM-31C
only)
Bit 3 = Terrestrial Yellow Alarm Received (T1 only)
Bit 4 = Terrestrial FAS Alarm Received (E1 only)
Bit 5 = Terrestrial MFAS Alarm Received (PCM-30 and PCM-
30C only)
Bit 6 = Loss of T4errestrial Signaling (reported by DSP)
Bit 7 = Spare
Bit 0 = Backward Alarm Received from Drop Terrestrial
Bits 2 – 7 = Spares
Force D&I Satellite Backward Alarm to be transmitted
Edit mapping of Satellite channels to dropped Terrestrial Time
Status Bytes
Decimal Point Implied
Bit 0 = Transmit Processor Fault Major Alarm
Bit 1 = Transmit Output Power Level Fault
Bit 2 = Transmit Oversample PLL Lock Fault
Bit 3 = Transmit Composite Clock PLL Lock Fault
Bit 4 = IF Synthesizer Lock Fault
Bit 5 = Transmit FPGA Configuration Fault
Bit 6 = Transmit Forced Alarm
Bit 7 = External Reference PLL Lock Fault
(0 = Pass, 1 = Fail)
Bit 0 = Terrestrial Clock Activity Detect Fault Minor Alarm
Bit 1 = Internal Clock Activity Detect Fault
Bit 2 = Tx Sat Clock Activity Detect Fault
Bit 3 = Tx Data Activity Detect Fault
Bit 4 = Terrestrial AIS (Tx Data AIS Detect Fault)
Bit 5 = Transmit Ext BNC Clock Activity Detect Fault
Bit 6 = Transmit Reed-Solomon Fault
Bit 7 = Tx BUC Fault, LBST Only
(0 = Pass, 1 = Fail)
Bit 0 = -12 V Alarm
4-52 TM065 – Rev. 3.3
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Latched Common
<1>
<1>
<1>
<1>
<1>
<1>
<1>
<2>
<4>
Latched Alarm 1
Major Alarm
Latched Alarm 2
Minor Alarm
Alarm
Online Flag
+5V Voltage
+12V Voltage
-12V Voltage
Temperature
Reserved
Bit 1 = +12 V Alarm
Bit 2 = +5 V Alarm
Bit 3 = Temperature Fault
Bit 4 = Interface FPGA
Bit 5 = Battery Fault
Bit 6 = RAM/ROM Fault
Bit 7 = Spare
(0 = Pass, 1 = Fail)
Bit 0 = Transmit Processor Fault Major Alarm
Bit 1 = Transmit Output Power Level Fault
Bit 2 = Transmit Oversample PLL Lock Fault
Bit 3 = Composite Clock PLL Lock Fault
Bit 4 = IF Synthesizer Lock Fault
Bit 5 = Transmit FPGA Configuration Fault
Bit 6 = Transmit Forced Alarm
Bit 0 = Terrestrial Clock Activity Detect Fault Minor Alarm
Bit 1 = Internal Clock Activity Detect Fault
Bit 2 = Tx Sat Clock Activity Detect Fault
Bit 3 = Tx Data Activity Detect Fault
Bit 4 = Terrestrial AIS (Tx Data AIS Detect Fault)
Bit 5 = Transmit Ext BNC Clock Activity Detect Fault
Bit 6 = Transmit Reed-Solomon Fault
Bit 7 = Tx BUC Fault, LBST Only
(0 = Pass, 1 = Fail)
Bit 0 = -12 V alarm
Bit 1 = +12 V alarm
Bit 2 = +5 V alarm
Bit 3 = Temperature Fault
Bit 4 = Interface FPGA Fault
Bit 5 = Battery Fault
Bit 6 = RAM / ROM Fault
-12 V, Implied Decimal Point and Minus Sign
(ex: 118 = -11.8 V)
Degrees C, Implied Decimal Point (ex: 490 = 49.0 C)
(Temperature is measured at the output amplifier, and does
not represent the overall internal temperature)
Ignore These Bytes
Note: The following three bytes apply only if an
asynchronous interface card, IDR or IBS interface card is
installed, and the AUPC option is installed and the AUPC
is enabled. If not, ignore this byte.
TM065 - Rev. 3.3 4-53
User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
<1>
<2>
<1>
<1>
<1>
<1>
Remote AUPC
Status
Remote AUPC
Eb/No
Daughter Card
Fault
Transmit IDR
Backward Alarms
Control Mode
Drop Alarm
Status
Drop Backward
Alarm Status
Bit 0 = AUPC Communication Error
Bits 1-2 = Eb/No Status
0 = Eb/No is Invalid
1 = Eb/No is Valid
2 = Eb/No is Smaller Than Indicated Value
3 = Eb/No is Larger Than Indicated Value
Unsigned Binary Value Decimal Point Implied
Note: The following byte applies only if an asynchronous
interface card, IDR or IBS interface card is installed, and
the AUPC option is installed and the AUPC is enabled. If
not, ignore this byte.
0 = Daughter Card OK
1 = Daughter Card Faulted
The following byte applies only if an IDR or IBS interface
card is installed and the modem is in IDR mode. If not,
ignore this byte.
Bit 0 = Backward Alarm 1
Bit 1 = Backward Alarm 2
Bit 2 = Backward Alarm 3
Bit 3 = Backward Alarm 4
Bits 4 – 7 = Spare
(0 = Not Transmitted, 1 = Transmitted)
0 = Front Panel, 1 = Terminal, 2 = Computer
Bit 0 = Terrestrial Frame Lock Fault (all modes)
Bit 1 = Terrestrial Multiframe Lock Fault (PCM-30 and
PCM-30C only)
Bit 2 = Terrestrial CRC Lock Fault (PCM-30C and PCM-31C
only)
Bit 3 = Terrestrial Yellow Alarm Received (T1 only)
Bit 4 = Terrestrial FAS Alarm Received (E1 only)
Bit 5 = Terrestrial MFAS Alarm Received (PCM-30 and PCM-
30C only)
Bit 6 = Loss of T4errestrial Signaling (reported by DSP)
Bit 7 = Spare
Bit 0 = Backward Alarm Received from Drop Terrestrial
Bits 2 – 7 = Spares
Opcode: <240Bh> Query a Modulator’s Status
Query Response
<1>
<1>
Revision Number
Alarm 1 Major
Alarm
Decimal Point Implied
Bit 0 = Transmit Processor Fault
Bit 1 = Transmit Output Power Level Fault
Bit 2 = Transmit Oversample PLL Lock Fault
Bit 3 = Composite Clock PLL Lock Fault
Bit 4 = IF Synthesizer Lock Fault
Bit 5 = Transmit FPGA Configuration Alarm Fault
4-54 TM065 – Rev. 3.3
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Bit 0 = Terrestrial Clock Activity Detect Fault
Bit 1 = Internal Clock Activity Detect Fault
Bit 2 = Tx Sat Clock Activity Detect Fault
Bit 3 = Tx Data Activity Detect Fault
Bit 4 = Terrestrial AIS (Tx Data AIS Detect Fault)
Bit 5 = Transmit Ext BNC Clock Activity Detect Fault
Bit 6 = Transmit Reed-Solomon Fault
Bit 7 = Tx BUC Fault, LBST Only
(0 = Pass, 1 = Fail)
Bit 0 = -12 V Alarm
Bit 1 = +12 V Alarm
Bit 2 = +5 V alarm
Bit 3 = Temperature Fault
Bit 4 = Interface FPGA Fault
Bit 5 = Battery Fault
Bit 6 = RAM/ROM Fault
Bit 7 = Spare
(0 = Pass, 1 = Fail)
Bit 0 = Transmit Processor Fault
Bit 1 = Transmit Output Power Level Fault
Bit 2 = Transmit Oversample PLL Lock Fault
Bit 3 = Composite Clock PLL Lock Fault
Bit 4 = IF Synthesizer Lock Fault
Bit 5 = Transmit FPGA Configuration Alarm Fault
Bit 6 = Transmit Forced Alarm
Bit 7 = External Reference PLL Lock Fault
(0 = Pass, 1 = Fail)
Bit 0 = Terrestrial Clock Activity Detect Fault
Bit 1 = Internal Clock Activity Detect Fault
Bit 2 = Tx Sat Clock Activity Detect Fault
Bit 3 = Tx Data Activity Detect Fault
Bit 4 = Terrestrial AIS (Tx Data AIS Detect Fault)
Bit 5 = Transmit Ext BNC Clock Activity Detect Fault
Bit 6 = Transmit Reed-Solomon Fault
Bit 7 = Tx BUC Fault, LBST Only
(0 = Pass, 1 = Fail)
Bit 0 = -12 V Alarm
Bit 1 = +12 V Alarm
Bit 2 = +5 V Alarm
Bit 3 = Temperature Fault
Bit 4 = Spare
Bit 5 = Battery fault
Bit 6 = RAM/ROM Fault
Bit 7 = Spare
Temperature is measured at the output amplifier, and does not
represent the overall internal temperature
Ignore These Bytes
Note: The following byte applies only if an asynchronous
interface card or an IDR or IBS interface card is installed,
and the AUPC option is installed and the AUPC is
enabled. If not, ignore this byte.
Bit 0 = AUPC Communication Error
Bits 1-2 = Eb/No Status
(0 = Eb/No is Invalid)
(1 = Eb/No is Valid)
(2 = Eb/No is Smaller than Indicated Value)
(3 = Eb/No is Larger than Indicated Value)
Note: The following two bytes apply only if an
asynchronous interface card or an IDR or IBS interface
card is installed, and the AUPC option is installed and the
AUPC is enabled. If not, ignore Note: The following two
bytes.
Unsigned Binary Value, Decimal Point Implied
Note: The following byte applies only if an IDR or IBS
interface card is installed. If not, ignore this byte.
0 = Daughter Card OK, 1 = Daughter Card Faulted
Note: The following byte applies only if an IDR OR IBS
interface card is installed and the modem is in IDR mode.
Bit 0 = Backward Alarm 1
Bit 1 = Backward Alarm 2
Bit 2 = Backward Alarm 3
Bit 3 = Backward Alarm 4
Bits 4 - 7 Spare
(0 = Not Transmitted, 1 = Transmitted)
0 = Front Panel, 1 = Terminal, 2 = Computer
Bit 0 = Terrestrial Frame Lock Fault (all modes)
Bit 1 = Terrestrial Multiframe Lock Fault (PCM-30 and
PCM-30C only)
Bit 2 = Terrestrial CRC Lock Fault (PCM-30C and PCM-31C
only)
Bit 3 = Terrestrial Yellow Alarm Received (T1 only)
Bit 4 = Terrestrial FAS Alarm Received (E1 only)
4-56 TM065 – Rev. 3.3
DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem User Interfaces
Latched Common
<1>
Drop Backward
Alarm Status
30C only)
Bit 6 = Loss of T4errestrial Signaling (reported by DSP)
Bit 7 = Spare
Bit 0 = Backward Alarm Received from Drop Terrestrial
Bits 2 – 7 = Spares
Opcode: <2405h> Query a Modulator’s Latched Alarms
Query Response
<1>
<1>
<1>
Latched Alarm 1
Major Alarm
Latched Alarm 2
Minor Alarm
Alarm
Bit 0 = Transmit Processor Fault
Bit 1 = Transmit Output Power Level Fault
Bit 2 = Transmit Oversample PLL Lock Fault
Bit 3 = Composite Clock PLL Lock Fault
Bit 4 = IF Synthesizer Lock Fault
Bit 5 = Transmit FPGA Configuration Alarm Fault
Bit 6 = Transmit Forced Alarm
Bit 1 = Internal Clock Activity Detect Fault
Bit 2 = Tx Sat Clock Activity Detect Fault
Bit 3 = Tx Data Activity Detect Fault
Bit 4 = Terrestrial AIS (Tx Data AIS Detect Fault
TM065 - Rev. 3.3 4-57
User Interfaces DMD2401/DMD2401L/DMD2401 IBS/IDR Satellite Modem
<1>
Common Alarm
Bit 5 = Transmit Ext BNC Clock Activity Detect Fault
Bit 6 = Transmit Reed-Solomon Fault
Bit 7 = Tx BUC Fault, LBST Only
(0 = Pass, 1 = Fail)
Bit 0 = -12 V Alarm
Bit 1 = +12 V Alarm
Bit 2 = +5 V alarm
Bit 3 = Temperature Fault
Bit 4 = Interface FPGA Fault
Bit 5 = Battery Fault
Bit 6 = RAM/ROM Fault
Bit 7 = Spare
(0 = Pass, 1 = Fail)
Opcode: <2433h> Query a Modulator’s RTS Level
Query Response
<1> RTS Level Bit 0 = Level
0 = Off, 1 = On
Bits 1 – 7 = Spares
Opcode: <2601h>Command a Modulator’s Configuration
<4>
<3>
<4>
<4>
<1>
<1>
<1>
<1>
<1>
<1>
<1>
Frequency
Reserved
Data Rate
EXC Clock
Modulation Type
Convolutional
Encoder
Reed-Solomon
Reed-Solomon N
Reed-Solomon K
Reed-Solomon T
RS Interleaver
Depth
Unsigned Binary Value in Hz
Set to Zero
Unsigned Binary Value in BPS
Unsigned Binary Value in Hz
0 = QPSK, 1 = BPSK, 2 = 8PSK, 4 = OQPSK
Note: The following command will also turn the carrier off
to protect the satellite.
Note: The following byte applies to all DMD2401 modems,
regardless of interface type.
0 = Normal, 1 = Swapped
Note: The following byte applies only if an Asynchronous
Interface Card, or an IDR OR IBS Interface Card is
installed, AND the AUPC option is also installed. If not,
set to zero.
Note: AUPC minimum power level < AUPC default power
level < AUPC max. power level.
0 = Disabled, 1 = Enabled
Note: The following two bytes apply only if an
Asynchronous Interface Card, or an IDR OR IBS Interface
Card is installed, AND the AUPC option is also installed.
If not, set to zero.
Note: AUPC minimum power level < AUPC default power
level < AUPC max. power level.
Unsigned Binary, 1 Decimal Point Implied
Note: The following two bytes apply only if an
Asynchronous Interface Card, or an IDR OR IBS Interface
Card is installed, AND the AUPC option is also installed.
If not, set to zero.
Note: AUPC minimum power level < AUPC default power
level < AUPC max. power level.
Signed Value, –50 to –300 (–5.0 to –30 dBm), Implied Decimal
Point
Note: The following two bytes apply only if an
Asynchronous Interface Card, or an IDR OR IBS Interface
Card is installed, AND the AUPC option is also installed.
If not, set to zero.
Note: AUPC minimum power level < AUPC default power
level < AUPC max. power level.
Signed value, –50 to –300 (–5.0 to –30 dBm), Implied Decimal
Point
Note: The following two bytes apply only if an
Asynchronous Interface Card, or an IDR OR IBS Interface
Card is installed, AND the AUPC option is also installed.
If not, set to zero.
TM065 - Rev. 3.3 4-61
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