RFM HN-591 User manual

HN-591
900MHz Desktop Wireless Modem
User’s Guide

Important Regulatory Information
Cirronet Product FCC ID: HSW-910M
IC 4492A-910M
Note: This unit has been tested and found to comply with the limits for a Class A digital
device, pursuant to part 15 of the FCC Rules. These limits are designed to provide
reasonable protection against harmful interference when the equipment is operated in a
commercial environment. This equipment generates, uses, and can radiate radio
frequency energy and, if not installed and used in accordance with the instruction manual,
may cause harmful interference to radio communications. Operation of this equipment in
FCC s MPE Requirements
Information to user/installer regarding FCC s Maximum Permissible Exposure (MPE) limits.
Notice to users/installers using the 8.5 dBi Yagi antenna with the WIT910.
FCC rules limit the use of this antenna, when connected to the WIT910 module, to point-to-point
applications only. It is the responsibility of the installer to ensure that the system is prohibited
from being used in point-to-multipoint applications, omni-directional applications, and
applications where there are multiple co-located intentional radiators transmitting the same
information. Any other mode of operation using this antenna is forbidden.
Notice to WIT910 users/installers using the following fixed antennas:
Cushcraft 8.5 dBi Yagi
The field strength radiated by this antenna, when connected to a transmitting WIT910, may
exceed FCC mandated RF exposure limits. FCC rules require professional installation of these
antennas in such a way that the general public will not be closer than 23 cm from the radiating
aperture of this antenna. End users of these systems must also be informed that RF exposure
limits may be exceeded if personnel come closer than 23 cm to the aperture of this antenna.
Notice to WIT910 users/installers using the following fixed antennas:
Cushcraft 6 dBi Monopole Cushcraft 3 dBi Omni Ace 2dBi dipole
The field strength radiated by any one of these antennas, when connected to a transmitting
WIT910, may not exceed FCC mandated RF exposure limits. FCC rules require professional
installation of these antennas in such a way that the general public will not be closer than 20 cm
from the radiating aperture of any of these antennas. End users of these systems must also be
informed that RF exposure limits may be exceeded if personnel come closer than 20 cm to the
apertures of any of these antennas.
Changes or modifications not expressly approved by the party responsible may void the users ability to
operate the equipment.

Table of Contents
Introduction .....................................................................................................................1
HopNet Frequency Hopping Spread Spectrum Advantages........................................1
HopNet Data Integrity...................................................................................................1
Flexible Power Management........................................................................................1
Data Transmission .......................................................................................................2
LED Status...................................................................................................................2
Power Connection........................................................................................................2
Antenna Connection.....................................................................................................2
Configuring the HN-591...................................................................................................3
Overview......................................................................................................................3
Introduction ..............................................................................................................3
HopNet Configuration Wizard (HNWizard)......................................................................4
Parameters Tab .......................................................................................................6
Network Tab.............................................................................................................9
Protocol Tab...........................................................................................................12
RF Tools ................................................................................................................14
Saving Configurations............................................................................................18
Modem Commands.......................................................................................................18
Serial Commands.......................................................................................................19
Set Data Rate Divisor.............................................................................................19
Set Protocol Mode..................................................................................................20
Network Commands...................................................................................................21
Set Transceiver Mode............................................................................................21
Set Default Handle.................................................................................................21
Enable Global Network Mode ................................................................................22
Set Hopping Pattern...............................................................................................22
Set Transmit Power................................................................................................22
Read Receive Signal Strength Indicator (RSSI).....................................................22
Protocol Commands...................................................................................................23
Set Alternative Frequency Band.............................................................................23
Set Hop Duration....................................................................................................24
Set Minimum Data Length......................................................................................24
Get Maximum Data Length (read only)..................................................................24
Set Maximum Number of Remotes (base only) .....................................................24
Set Packet Attempts Limit......................................................................................24
Set Data Transmit Delay........................................................................................25
Set Slot Assignment Mode (base station only).......................................................25
Set Base Slot Size (base station only)...................................................................25
Set ARQ Mode.......................................................................................................25
Status Commands......................................................................................................26
Banner Display Disable..........................................................................................26
Set Escape Sequence Mode..................................................................................26
Read Factory Serial Number High, Middle and Low Bytes. ...................................27
Set Duty Cycle .......................................................................................................27
Memory Commands...................................................................................................28

Recall Factory Defaults..........................................................................................28
Recall Memory.......................................................................................................28
Store Memory.........................................................................................................28
Modem Command Summary .....................................................................................29
Typical HopNet Applications .........................................................................................30
Introduction ................................................................................................................30
Point to Multipoint...................................................................................................30
Point-to-Point .........................................................................................................31
Troubleshooting ............................................................................................................32
Overview....................................................................................................................32
Introduction ............................................................................................................32
Transceiver Requirements.....................................................................................32
Common System Problems........................................................................................33
Guidelines for Reducing Interference.........................................................................34
Introduction ............................................................................................................34
Guidelines for Selecting Your Site..........................................................................34
Guidelines for Avoiding Terrain Obstructions.............................................................34
Customer Support.........................................................................................................35
Introduction ................................................................................................................35
Technical Assistance..................................................................................................35
Factory Repairs..........................................................................................................35
Glossary of Terms.........................................................................................................36
Technical Specifications................................................................................................37
General ......................................................................................................................37
Mechanical.................................................................................................................37
Mechanical.................................................................................................................38
Environmental ............................................................................................................38
Appendix A....................................................................................................................39
HNWizard INIT.INI File...............................................................................................39
HNWizard’s WinCom Window....................................................................................40
Function Keys ........................................................................................................43
Recover..................................................................................................................43
Restart ...................................................................................................................44
Warranty........................................................................................................................45

HN-591
Introduction
The HN-591 provides reliable wireless connectivity for either point-to-point or point-
to-multipoint applications. The HN-591 is built around the WIT910 radio transceiver,
which employs frequency hopping spread spectrum technology. This technology
ensures:
•Maximum resistance to noise
•Maximum resistance to multipath fading
•Robustness in the presence of interfering signals
In addition, the HN-591 includes a rechargeable battery pack allowing 2+ hours of
operation without mains power. Battery operation makes the HN-591 ideal for site
surveys. The sleek, rugged styling of the HN-591 enclosure enables deployment in
any environment.
HopNet Frequency Hopping Spread Spectrum Advantages
In the frequency domain, a multipath fade can be described as a frequency selective
notch that shifts in location and depth over time. Multipath fades typically occupy
five percent of the band. A conventional radio system typically has a five percent
chance of signal impairment at any given time due to multipath fading.
Frequency Hopping Spread Spectrum reduces the vulnerability of a radio system to
both interference from jammers and multipath fading by distributing or spreading the
signal over a larger region of the frequency band.
The fade resistant, HopNet frequency-hopping technology employs up to 54 channels
and switches channels over 40 times a second to achieve high reliability throughput.
HopNet Data Integrity
An on-board 512B buffer and error correcting over-the-air protocol ensure data
integrity even in the presence of weak signals or jammers. The serial interface
handles both data and control of asynchronous data rates of up to 115Kbps.
Flexible Power Management
The power can be set at 10 milliwatts, 100 milliwatts or 500 milliwatts using the
included software. Reduced power can reduce the size of the coverage zone, which
may be desirable for multiple network indoor applications. You can also place the
transceiver module in a power-save mode, which enables smart power management.
Smart power management allows a remote unit to drop into a lower current standby
mode during transmission or receiving gaps.
This feature also allows Hopnet products to be used in various countries where the
output power requirements may vary due to regulation.
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Data Transmission
The HN-591 can be used as either a base or as a remote. The HN-591 can usually
transmit to 1000 feet indoors and in excess of 20 miles outdoors under ideal
conditions.
The automatic repeat requests (ARQ) and multinode protocol are transparent to the
user equipment. User data rates of 115Kbps are supported with built-in CRC/ARQ
error protocols. Data signals are EIA RS-232 standard for Data Communications
Equipment (DCE) devices.
Data and control of the radio are passed through a standard DB9 connector. See the
following illustration for the signal description.
LED Status
The four LED indicators are included on the front panel to provide the status of the
HN-591 Indoor Base/Remote station. See the illustration below. These built-in flow
control indicators allow you to quickly check the operational status.
PWR TX RX CD
The table below describes the function of each LED.
Name Color Description
PWR Green/Red Continuous DC power is applied
TX Red RS-232 signal input
RX Red RS-232 signal output
CD Red Normal operation is asserted
Power Connection
The HN-591 is supplied with a 110VAC wall mount power supply. However, you can
operate the HN-591 from any well-filtered 5 VDC power source. The power supply
should be capable of providing 1 Amp of current.
The HN-591 also has a built in battery pack that allows use of the modem without
being tethered to a power source. The battery pack charges any time the unit is
plugged in. An amber colored LED on the rear of the unit next to the power
connector indicates that the internal battery pack is charging.
Antenna Connection
The RF signal is brought in on a reverse male SMA jack connector located on the
back panel. The HN-591 comes with a 2 dB omni-directional antenna. Be sure to
securely fasten the antenna.
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Configuring the HN-591
Overview
Introduction
You can configure the HopNet network using the HNWizard software provided or a
PC running a terminal emulation program. HNWizard is a software package that runs
under Windows 98/NT/2000/XP. This chapter provides the information you need to
configure your HN-591.
The HN-591 is shipped from the factory initially configured as a remote with a 9600
baud rate.
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HopNet Configuration Wizard (HNWizard)
Open the Wizard by double-clicking on the icon on the desktop. When the Wizard
boots up, it will automatically detect the serial port to which the HopNet radio is
connected and its baud rate. This process takes a few seconds to complete. During
this process, the “Please wait” screen is displayed. Once the radio has been found and
the Baudrate determined, the “Finished” screen is displayed. Click on the Continue
button to enter the Wizard.
NOTE: HNWizard is used with a variety of Cirronet radios. Not all radios support
all the functions and features of every Cirronet radio. Thus, some selections in the
Wizard will be grayed out if they are not applicable to the radio in use.
After detecting the serial port and baud rate of the HopNet radio, the Wizard reads the
settings of the HopNet radio that is connected to the PC and will display them in the
various parameter windows. In the bottom left corner of the Wizard window, the
Base/Remote status, the serial number and the communication port are always
displayed.
NOTE: The S/N displayed in the bottom left corner is the serial number of the
radio inside the unit and is different from the serial number of the HopNet unit.
Both the HopNet unit serial number and the radio serial number are on the radio
unit of the HopNet product. The Wizard will also prompt to save the configuration
settings to a file.
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When a parameter value is changed from the value currently in the HopNet radio, the
parameter label and value will turn red and the Apply Settings button will appear.
When the value is changed back to the value that is currently in the attached HopNet
radio, the label and parameter value will return back to black. When new values are
applied to the HopNet radio, the red values will turn black indicating the updated
values in the radio.
NOTE The changes are not sent to the HopNet radio until the Apply Settings
button is clicked.
Context sensitive help is available through the F1 key or Help menu.
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Parameters Tab
The Wizard program opens the main screen with the Parameters Tab displayed. The
parameters screen of the Wizard allows the following variables to be set;
1. Base or Remote
2. Point-to-Point or Multipoint
3. Baud rate
4. Network number
5. Lockout Key
6. Roaming Mode
7. Protocol Mode
Depending on whether HopNet radio is configured as a Remote or Base when first
connected, the heading on the Parameters page will display either “Remote
Parameters” or “Base Parameters.”
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Network Number
This parameter is also known as Set Hopping Pattern. By using different network
numbers or “hopping patterns”, nearby or co-located networks can avoid interfering
with each other’s transmissions.
BaudRate
Sets the serial bit rate between the modem and the host.
Lockout Key
This parameter allows further network segregation beyond the network number. This
feature allows multiple co-located networks in which global roaming is enabled. By
using different lockout keys, the bases to which remotes link can be limited or
segregated.
Serial Port Settings
This parameter is only available on radios with Modbus adapters.It allows the setting
of even, odd or no parity, 7 or 8 data bits and 1 or 2 stop bits.
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Roaming Mode
This parameter allows remote radios to link to any base station or only link to specific
base stations.
Protocol Mode
This parameter enables the base station to operate in a multipoint network.
Depending on the user application, more or less acknowledgment may be desired by
the application. Remotes can operate in transparent mode even though the base
station is operating in one of the nontransparent modes. When using a protocol mode,
make sure to count in packet overhead when calculating network performance. Refer
to the section on Protocol Modes for details on each format.
When the radio is linked to another radio, a communications test can be run by
clicking on the Send Data button (shown below) on both radios. The remote radio’s
Transmit Data window (above left) will display the message, “This is a test message
from the Base radio”, which will repeat until the Stop button is pressed (on the base
radio’s HN Wizard main screen). The base radio’s Transmit Data window (above
right) will display the message, “This is a test message from the Remote radio” which
will repeat until the Stop button is pressed (on the remote radio’s HN Wizard main
screen).
Send Data
The Send Data button (shown below) initiates the transmission of data.
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Default
The Default button (shown above) returns all parameters to Factory settings.
Network Tab
Clicking on the Network tab will bring up a second configuration screen. From this
screen it is possible to change the dwell time at which the HopNet radio hops, set a
minimum number of bytes of data the radio must receive before it will transmit, set a
maximum amount of time the radio will wait to receive the minimum number of bytes
before transmitting what is in the radio’s buffer and set the number of times the radio
will repeat a transmission that is not acknowledged before discarding the data.
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Set Data Transmit Delay
When used in conjunction with the minimum data length parameter, sets the amount
of time from the receipt of a first byte of data from the host until the radio will
transmit in transparent mode. Default is 0.0ms which causes transmission to occur
without any delay. When a host is sending a group of data that needs to be sent
together, setting this parameter will provide time for the group of data to be sent by
the host before the radio transmits. If the length of data to be sent together is longer
than the time slot can send, the data will not be sent together but will be broken up
over multiple hops. The length of time the radio will wait is equal to the specified
value times the hop duration.
NOTE: The Transmit Delay is specified as a number of hop durations and thus will
be an integer multiple of the Hop Duration. The Maximum Base Packet can only
be set in radios set as a base. If the radio is a remote, this value cannot be changed.
Maximum Base Packet (base station only)
This command sets the amount of time allocated for transmission on each hop for the
base station time slot in 4-byte increments. If using a protocol mode, attempting to
send a packet with a length longer than this setting will cause the packet to be
discarded.
Set Minimum Data Length
This command sets the minimum threshold number of bytes required to form a packet
in transparent mode. The radio will wait until the data transmit delay elapses before
sending a data packet with less than this number of bytes. This parameter can be used
to keep short, intermittent transmissions contiguous. In packet modes, the length
parameter in the data packet will override this value. This value is subject to the
maximum data length even in packet mode.
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Set Packet Retries
If ARQ Mode is set to 0, it sets the number of times the radio will attempt to send an
unsuccessful transmission before discarding it. If ARQ Mode is set to 1, it is the
number of times every transmission will be sent, regardless of success or failure of a
given attempt. When this parameter is set to 255, RF flow control mode is entered for
transmissions from the radio. This mode can be entered for one or both radios in a
point-to-point system. Using this mode in a point-to-multipoint system will stop
transmissions to all radios when any one radio has a full buffer.
Set Hop Duration
This command sets the length of time the transceiver spends on each frequency
channel. A smaller value will allow the remote to lock on to the base signal faster at
system startup, and will generally decrease packet latency. A larger value increases
network capacity, due to decreased overhead in channel switching. This Set Hop
Duration value only needs to be set in the base which broadcasts the parameter to all
remotes. However, link time can be reduced if this value is also programmed into the
remotes, which use it as a starting value when scanning for the base.
The speed at which the radio hops affects both latency and throughput. The faster the
radio hops, the shorter the latency but the lower the throughput. The minimum packet
length and packet timeout allow fixed-length packets of data to be transmitted on a
single hop without leaving data stuck in the radio’s transmit buffer.
NOTE: If the hop speed is too fast, there may not be time to send a long packet on a
single hop.
Refer to the Protocol Commands section of this manual for details on these
commands.
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Protocol Tab
The Protocol tab brings up the configuration screen above. On the next page are
descriptions of the commands/parameters that are available for modification.
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Set the Frequency Operating Range
by clicking on the drop-down menu
and making a selection. ¹
Set Radio Power Setting up by
clicking on a selection. ²
Note: This list will change depending
on which radio is being used.
Set Maximum Number of Remotes
from1 to 62.
Set Redundant Transmit by
selecting either ARQ enabled or ARQ
disabled.
Choose to have the Banner Display
or not by selecting Banner disabled or
Banner enabled.
Choose the type of Escape Sequence
by selecting Once after reset or
Unlimited times.
¹ The selections in this field will change depending on the frequency band the radio operates in. For 2.4GHz
radios, selecting one of the 802.11b bands in which to operate, the HopNet radio can be used in locations with
802.11b networks without causing interference with those networks. If there are no 802.11b networks present, it
is recommended that the radio be set to operate in the entire band which is the default. For 900MHz radios, there
will only be two bands to select.
² The Radio Power Setting controls how much power is used to transmit data. Unless the HopNet radio operates in
the 2.4GHz band and is being used in the European Union (EU) this setting should be left at the default High
Power. Because of the built-in antenna of the HopNet radio, the 10mW power setting must be used when
operating in an EU country.
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RF Tools
Clicking on the RF Tools tab brings up a screen that allows the receive signal strength
to be monitored and the link quality to be observed. Range Optimization may be
grayed out on certain radios.
NOTE: RF Tools only work on HopNet radios operating as remote radios. The
radio must be linked with its base radio for the functions on this screen to work.
Range Optimization (HopNet 10 Series only)
This command automatically applies an adjustment factor to the over-the-air timing
of remotes to compensate for the effects of propagation delay at long ranges. Simply
click on the radio button opposite Range Optimization and the following screen will
display.
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Click on OK and the Select Connect Range screen will appear.
Click on the estimated distance between radios and click OK.
A bar will appear showing the progress of Range Optimization. Once the process has
completed, the Range Optimization radio button will clear and the Done radio button
will fill in indicating that adjustment factor has been applied.
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Receive Only and Bi-Directional Transmissions
The Receive Only function displays the percentage success rate for receiving
transmissions from the base. This is an indication of how well the remote HopNet
radio “hears” the base. The Bi-Directional function provides a round-trip success rate.
That is, the base must successfully receive data from the remote and the remote must
successfully receive data from the base. In theory, this percentage should be the
square of the Receive Only percentage. If it is substantially less, it is an indication
that the base HopNet radio is having difficulty “hearing” the remote. Good RF links
will have the Receive Only percentage above 95% and the Bi-Directional percentage
above 90%. These functions operate with the Automatic Retransmit Request (ARQ)
disabled and as such provide an indication of link quality but do not provide an
indication of how often data will get through since in normal operation ARQ is
enabled and the radio automatically and transparently will resend data that was not
received on the first attempt.
NOTE: The Options menu allows for bar graph display (in addition to the pie chart
display) of the Receive Good Packets and Bi-Directional Good Packets data.
Received Signal Strength Indication.
This function will display on a channel basis, the strength of the signal received from
the base by the remote. The values on the Y-axis are only approximate and should not
be used as absolute reading values.
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