Synapse SNAPlink User manual

USER GUIDE
SNAPlink
Wireless Serial Adapter for RS-232 and RS-
485/RS-422 Devices
©2008-2017 Synapse Wireless, All Rights Reserved. All Synapse products are
patent pending. Synapse , the Synapse logo, SNAP, and Portal are all registered trademarks
of Synapse Wireless, Inc.
Doc# 116-081614-031-B000
6723 Odyssey Drive // Huntsville, AL 35806 // [phone] // Synapse-Wireless.com

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NOTE: This equipment is meant to be installed in accordance with all applicable local, state, and national
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Instructions
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Table of Contents
Introduction 1
Download Supporting Materials 1
Document Conventions 1
Getting Started 2
Powering the SNAPlink 2
Understanding Point-to-Point Mode 2
Understanding Multipoint Mode 2
Defaulting to Broadcast State 4
SNAPlink LED Indicators 4
Installing and Using the SNAPlink EasySet Software 6
Installing EasySet 6
Using EasySet 7
Connect a SNAPlink Device 7
Selecting Basic Communications Settings 8
Configuring Your Adapter Using DIP Switches 17
DIP Switch 1 17
DIP Switch 2 19
Troubleshooting 20
Signal Strength Problems 20
Multiple Masters 20
Can’t Find a Master 21
Poor Performance 21
Paired But Not Communicating 21
Specifications 22
Pin Outs 25
Regulatory Information and Certifications 27
RF Exposure Statement 27
FCC Certifications and Regulatory Information (USA Only) 27
Declaration of Conformity 28
Industry Canada (IC) Certification 28

Introduction
The SNAPlink family of industrial-class, mesh networking, wireless serial
adapters allows you to wirelessly connect RS-232 and RS-485/422 serial
devices. SNAPlink adapters provide the highest data-rates, longest
distance, and most reliable signal in the industry.
SNAPlink adapters are configured using internal DIP switches or the
SNAPlink EasySet software, an intuitive application running on Microsoft®
Windows®-based computers that allows you to configure the device quickly
and easily. Please refer to the Specifications on page 22 for exact
operating system requirements.
Download Supporting Materials
You can find SNAPlink documentation, including this User Guide and the Quick Start guide packaged with your
device, online at:
http://info.synapse-wireless.com/SNAPlinkintro
You can also download the EasySet software from that site, allowing you even more configuration and control over
your SNAPlink devices.
Document Conventions
Please note the following terminology while reading this document:
lThe term SNAPlink is used to refer to any of the SNAPlink models listed above.
lThe RS-232 models are referred to by their model number, SL232.
lThe RS-485/422 models are referred to by their model number, SL485.
lThe term serial port refers to the data communications port – either the RS-232 port (DE-9F connector) of an
SL232 device or the RS-485/422 terminal block of an SL485 device.
lThe micro-USB port of the SNAPlink adapter may be referred to as simply the USB port.
lThe term RS-232 device or RS-485/422 device refers to the data communications device you are attaching
to the SNAPlink adapter.
lThe term UART Parameter refers to SNAPlink configuration settings that indicate how quickly data is
wirelessly transmitted based on serial data that is received from the serial device.
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Getting Started
SNAPlink devices provide many configuration options for compatibility with nearly any RS-232, RS-422, or RS-485
device. This section provides instructions to get your devices up and running in using the DIP switches inside the
devices, or the EasySet software.
Powering the SNAPlink
You can power your SNAPlink units with 6–30 volts DC connected to the power terminal blocks, or through its
USBconnection.
You may use the terminal blocks to provide power even when you have the device connected to a computer for
configuration (using the EasySet software) or for data transfer, though when connected to a USBport there is no
need for additional power. If you have both power options connected and disconnect one, the SNAPlink seamlessly
switches to the other power source.
Hand-tighten the terminal block screws. (To between 0.35 and 0.40 Nm (3.1 to 3.5 inch pounds) for best results.)
Understanding Point-to-Point Mode
All models of SNAPlink can operate in either point-to-point mode, also known as unicast, or in multipoint mode, also
known as multicast.
In point-to-point mode two SNAPlink units are paired, thereby providing a wireless connection between two external
serial devices.
To pair a point-to-point configuration:
1. Make sure both devices are powered.
2. On one SNAPlink device, hold the button for at least 5 seconds, until LEDA turns red. Release the button and
LEDA should be flashing red.
3. Repeat this process on the second SNAPlink device.
You should now find that LEDA on both devices changes to solid green.
NOTE: If you have an exceptionally noisy RFenvironment, you may find that one or both of the devices have
LEDA flashing amber rather than green. If this occurs, you should consider switching your devices to a different
SNAPchannel, which would use a different radio frequency. You can make this change using the EasySet
software or using the DIPswitches inside the SNAPlink device.
Understanding Multipoint Mode
In multipoint mode, one of the SNAPlink devices is designated the master and one or more other devices can be
configured as slaves. In this configuration, messages sent by the master will be sent to all slave devices, while

messages sent by the slaves will be received only by the master unit.
For example, imagine a installation where doors are controlled by access card readers. Each reader uses serial
communications to report access information back to a hub. A single master unit could be used to receive serial
information from each of the individual doors. The master unit could also be used to broadcast information back to all
readers, provided you don't mind them all receiving the same message.
To pair a point-to-multipoint configuration:
In a point-to-multipoint configuration, your master device sends communications heard by each of the slave devices,
but the slaves can only send data back to the master.
1. Make sure all devices are powered.
2. On the master SNAPlink device, press the button four times within a 3-second period. LEDA should switch to
flashing amber. Again, push the button four times within a 3-second period. LEDA should switch to a slow
flash between green and amber, indicating that it is a master unit.
3. For each slave SNAPlink device, press the button four times within a 3-second period. LED A may briefly
switch to flashing amber, but should quickly go to a solid green, indicating that it has found its master. (If you
have an exceptionally noisy RFenvironment, you may find that one or more of the slave devices have LEDA
flashing amber rather than green. If this occurs, you should consider switching your devices to a different
SNAPchannel, which would use a different radio frequency. You can make this change using the EasySet
software or using the DIPswitches inside the SNAPlink device.)
NOTE: If you have an exceptionally noisy RFenvironment, you may find that one or both of the devices have
LEDA flashing amber rather than green. If this occurs, you should consider switching your devices to a different
SNAPchannel, which would use a different radio frequency. You can make this change using the EasySet
software or using the DIPswitches inside the SNAPlink device.
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Canceling Pairing State
If you accidentally put a unit into Pairing state, while LED A is rapidly flashing red, hold down the MODE button until
LEDA goes dark, about 5 seconds. The unit is now back in Broadcast state.
Unpairing Units
If you have SNAPlink devices that are paired to each other and you wish to return them to Broadcast state, hold the
MODE button until LEDA turns red, about 5 seconds. Release the MODE button. This will cause the device to drop
its current partner and go into Pairing state. From there you can cancel the Pairing state to return to Broadcast state,
or introduce it to a new SNAPlink device in Pairing state with which it will connect.
Demoting a Multipoint Mode Master
If you have a SNAPlink device set as a multipoint master, hold the MODE button about 5 seconds until LEDA rapidly
flashes amber. This sets the unit back to multipoint pairing state, seeking a multipoint mode master. Any multipoint
mode slaves that had been pair with this device before its demotion should be re-paired with the new multipoint
mode master.
Exiting Multipoint Mode
For a SNAPlink device in multipoint pairing state or for a multipoint mode slave device, press and hold the MODE
button until LEDA glows steadily, about five seconds, to return the device to Broadcast state. LEDA will turn off. The
device is now ready to be configured for point-to-point mode or multipoint mode.
Defaulting to Broadcast State
To return a SNAPlink to Broadcast state and set its network and serial settings based on the internal DIPswitches,
disconnect power from the device, hold the MODE button, and reapply power. After 5 seconds, the LEDs will rapidly
flash green-amber-red. Release the MODE button.
This should leave LEDB green (indicating power), LED A off (indicating Broadcast state), and LEDC green if an RS-
232 connection is made.
SNAPlink LED Indicators
Each SNAPlink device has three LEDs on it, labeled A, B, and C, on the end with the RP-
SMA antenna connection.

LED LEDState Description
A
OFF Default State
Rapidly flashing Red Unit is seeking a pair
Solid Green Unit is paired with a strong signal
Solid Amber Unit is paired with a weak signal
Solid Red Unit is paired with a weak or no signal
Any Color and flickering Wireless communications are occurring
Flashing Amber Unit is in multipoint mode and seeking a master
Slowly alternating between
green and amber Unit is in multipoint master mode.
Slowly alternating between
red and amber
Unit is in multipoint mode and has detected another master on
the same channel and network
B
Solid Green Unit is powered
Flickering Green Unit is communicating on the USBport
C
Solid green An RS-232 device is attached and idle
Flickering green An RS-232 device is attached and data is being transferred
Off (while powered) An RS-485/422 device is attached and idle
NOTE: It may be difficult to differentiate an amber colored LED from one showing green or red, depending upon
your viewing angle. When viewed from above, an amber LED may look red and when viewed from below it might
look green. If in doubt, try viewing the LED at different angles.
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Installing and Using the SNAPlink EasySet Software
The SNAPlink EasySet software provides a graphical interface for configuring the SNAPlink and accessing settings
like bps rate, flow control, and parity bits.
EasySet is currently available for Microsoft Windows 7 and newer operating systems, and can be downloaded from
the Synapse Wireless website at:
http://info.synapse-wireless.com/SNAPlinkintro
After downloading the software launch the installer to guide you through the installation process.
NOTE: The EasySet software overrides the dip switches on the SNAPlink device. If you use EasySet, any
configurations made with switches must be repeated within the software.
Installing EasySet
Launch the installer and step through the installer process, accepting the software license, to complete the software
installation.
You will be offered the opportunity to install SNAPUSBdrivers, as shown on this screen:
These drivers are needed for EasySet to communicate with the SNAPlink device. If you configure your SNAPlink to
use the USBconnection as its serial input source, you will also need these drivers installed on the computer sending
data. Be sure to disconnect any Synapse USBdevices from your computer as the installer runs. (The installer will
prompt you with a reminder for this when it is appropriate.)

Using EasySet
Launch EasySet by selecting EasySet from the Windows Start menu. EasySet
will start up and present this window. You will see four icons in the tool bar
across the top of the window. Most of these are inactive (grayed out) until
EasySet is connected with a SNAPlink adapter. There are also five tabs in a tab
bar below the tool bar.
Toolbar
The four toolbar commands are:
Connect / Disconnect Serial Port – connects or disconnects from
the attached SNAPlink device. Because this icon changes when you
connect or disconnect, it also serves as a quick
status indicator.
Ping – causes EasySet to make a quick connectivity test to the
attached SNAPlink device.
Refresh Node Information – causes EasySet to poll the attached
SNAPlink device for configuration information.
Upload SNAPpy Image – prompts EasySet to upload the SNAPlink
operating software into the attached SNAPlink device. This is only
necessary on release of new SNAPlink software, or if instructed by
technical support.
Connect a SNAPlink Device
Connect a SNAPlink device to your computer using the supplied USB cable. The micro-B USB end of the cable fits
into the back of the SNAPlink device, and the type-A USB end fits into any standard USB port on your PC. This
connection supplies power to the SNAPlink and also allows EasySet to communicate with it.
Press the Connect Serial Port button. EasySet will scan all serial ports and will stop when it has found a SNAPlink
device.
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When EasySet finds a Synapse device, click the Connect button. If it failed to find the correct device type, press the
Scan button ( ) to the right of the port identifier. This will instruct EasySet to continue the scan.
When successfully connected to a SNAPlink device, EasySet populates the communication fields with the data
currently set in the SNAPlink device.
When the SNAPlink device is powered up for the first time, you will see the factory default settings set internally by
the DIP switches. Once the configuration is changed by EasySet, the SNAPlink device will retain the new
configuration in flash memory.
Tab Bar
There are five tabs across the top of the window — Basic, Mesh, UART, Pairing, and Advanced — which allow you to
match the communications settings of your SNAPlink adapter to the serial device you're connecting to.
Selecting Basic Communications Settings
Below the icons and immediately above the tab bar is the SNAPlink
adapter type: either RS-232 or RS-485/422. To the right of that is the
last three bytes of the adapter’s MAC (media access control) address.
(The MAC address is also in the title bar, and printed on a label on the
device.)Finally, the PC-assigned COM port is listed to the right of the
MACaddress.
Basic Tab
The Basic tab provides information and configuration options for how
your SNAPlink device will communicate with other SNAPlink devices
and with the connected serial device.
The first three options indicate the loaded device script, and the
network ID and channel on which it will communicate.

Firmware The Firmware field displays the name of the script loaded into your SNAPlink device.
This will be SNAP_Link unless Synapse Customer Support has provided an alternate.
Network
ID
The Network ID can be thought of as a logical channel. This 16-bit integer may be
assigned any hexadecimal value from 0x0001 through 0xFFFE. Devices in a SNAP
network must share both the same channel and same network ID to communicate. This
allows multiple SNAP networks to share the same channel if required, although it is
preferred to place independent networks on separate physical channels to reduce
collisions. SNAPlink defaults to network ID 0x1C2C.
Channel
The Channel number can range from 0 to 14, and corresponds to specific radio
frequencies in the 2.4 GHz band. (Channel 15 cannot be used for data transmission due
to FCCregulations.) All SNAPlink devices that you wish to include in the same network
must be set to identical channel numbers.
SNAPlink devices default to channel 4. If you do not have EasySet available, you can
modify your channel setting using DIPswitches inside the SNAPlink enclosure. See the
DIP Switch 1 section for details. Defaulting the device by holding the button while
powering up will set it to use the channel specified by the DIPswitches.
The remaining fields on the Basic tab relate to the connected serial device. Typically these values will depend on the
target device. Set the items under the Basic tab to match the connected serial device.
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Data
UART
SNAPlink adapters contain two UART (Universal Asynchronous Receiver/Transmitter)
connections, one for the USB port and one for the serial communications (RS-232 or RS-
485/422) port. This setting indicates which port is connected to your serial device and
where the serial data should be transmitted or received. The factory default is to send all
serial data through either the RS-232 DE9 or RS-485/422 terminal block and NOT through
the USB cable. This leaves the USB port as the means to communicate with EasySet.
You can change this arrangement, but it will make your device unreachable via the USB
port for further programming by EasySet. If you choose "USB" using this Data UART
setting in EasySet and later need to reprogram the device, the easiest method is to reset
the device to its default settings. Alternately, if your computer has an RS232 port or if you
have an adapter to connect to the RS-232 or RS-485 port on your SNAPlink device, you
could use that connection to connect to EasySet.
Bps
Rate
Set the SNAPlink bps rate to match that of your serial device. The bps rate for all devices
can range from 300 to 115,200. Adapters can send chunks of data in bursts up to 115,200,
and safely sustain a maximum of 19,200 bps if one device is sending data, or 9,600 if two
devices are constantly sending data to each other.
SNAPlink devices default to 9,600 bps. If EasySet isn't available, you can modify your bps
rate using DIPswitches inside the SNAPlink enclosure. See the DIP Switch 1 section for
details. Defaulting the device by holding the button during power-up will set it to the value
specified by the DIPswitches and clear other routing configuration changes to defaults.
Changing the DIP switches and power cycling the device will change the bps rate (and/or
SNAP radio channel) without affecting other configuration changes.
Data
Bits Set the number of data bits to 7 or 8. The default is 8.
Parity Set the parity to none, odd, or even. The default is none.
Stop
Bits Set the stop bits to 1 or 21. The default is 1.
Flow
Control
This setting should only be enabled for devices needing flow control. RS-485 and RS-422
devices always have flow control enabled. For RS-232 devices, the default is disabled.
If you do not have EasySet available, you can modify your flow control setting using a
DIPswitch inside the SNAPlink enclosure. See the DIP Switch 1 section for details.
Defaulting the device by holding the button during power-up will set it to the value
specified by the DIPswitch.
1Early SNAPlink devices required that stop bits always be set to 1. The current version allows either 1 or 2.

Mesh Tab
The Mesh tab allows you to tune your network to accommodate unusual environments, such as when you need
intermediate nodes to forward your data in case of great distances or interference.
Typically one of the two preconfigured options, "Mesh" or "No Mesh" will be appropriate for your application.
Mesh Routing Settings
SNAP-based nodes in a complex environment will constantly update
their communication routes to provide the best path for getting all
messages from origin to destination. These routes expire (every
minute, by default) and are re-established to be certain that the most
efficient path is always in use.
If you configure your SNAPlink device as a mesh device, you are
allowing the device to assist other SNAP-based nodes in its
environment (with the same channel and network) with their
communications. This can make those communications more robust,
but does so at the potential expense of interrupting or bottlenecking
communications between your SNAPlink devices. If you have fairly
low data throughput requirements for your SNAPlinks, you are not
likely to have problems with the Mesh configuration enabled. If you
have only your network of intercommunicating SNAPlink devices (two
paired, or a point-to-multipoint collection), and each node is able to communicate reliably with each of its partners,
there is no need to enable the Mesh configuration.
If, however, you have a point-to-multipoint configuration where one or more of the slaves is not able to reliably reach
the master, or vice versa, it can help to have an intermediate device (including another slave device in your network)
set to enable the mesh configuration to help pass data along.
Configuring your devices with the Mesh settings can also be helpful in an environment where you have multiple
paired devices on the same channel and network ID, where one (or more) of the pairs may be at the limits of their
ranges. Paired SNAPlink devices will still be willing to assist other SNAPlink devices with their communications, even
though they will not act on those communications themselves.
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No Mesh
In contrast, the No Mesh configuration tells a device to not aid other devices when they are trying to establish routes.
With the No Mesh configuration, each node is still perfectly happy to make use of other willing participants in the
mesh network, but will not volunteer to forward messages for other nodes.
The advantage of this configuration, even in an isolated environment without outside nodes asking for assistance, is
your devices will perform their route discovery tasks once and then not allow those found routes to time out,
reducing a small amount of overhead every minute or so. This means if your devices spend a significant amount of
time idle and then need to send a burst of data, that burst will not be subjected to increased latency by the need for
route discovery.
Mesh Routing Maximum Timeout
The Mesh Routing Maximum Timeout setting specifies how long a discovered route can survive before it is
discarded and route discovery has to happen again. The Mesh configuration sets this to 60,000 milliseconds, or one
minute. (The maximum value is 65,535 milliseconds.) Setting the value to zero instructs that routes should never
time out, and will only be discarded if they are found to be unusable. The No Mesh configuration sets this to zero.
Mesh Override
The Mesh Override setting specifies whether a device is willing to pass along directly addressed messages for
other devices. Devices that are directly paired and slave nodes in a point-to-multipoint arrangement send their
messages as addressed messages, so these could be affected by this setting. If you have multiple paired point-to-
point devices, these devices could also be configured to route and relay messages for each other.
Turning Mesh Override off does not mean that the device is unable to take advantage of the mesh network for its
own purposes. It only means that it will not be a polite citizen in its mesh environment, forwarding directly addressed
messages for other nodes.
Disabling this setting on an intermediate SNAPlink device in an environment where one or more devices have
difficulty communicating reliably with another device can allow that intermediate device to relay the other slaves'
messages to the master.
In an environment where every SNAPlink device can directly communicate with every other device this setting is
irrelevant.
Multi-cast Forwarded Groups
The Multi-cast Forwarded Groups setting performs a similar function as the Mesh Override setting, only for
multicast messages rather than for directly addressed messages. In the context of SNAPlink devices, the only
multicast messages typically sent are from the master to the slave(s) in a point-to-multipoint configuration.
Enabling this setting on an intermediate SNAPlink device in an environment where the master has difficulty
communicating with one or more slaves can allow that device to relay the master's messages to the more slaves.
In an environment where every node can directly communicate with every other node, this setting is unnecessary,
and enabling it can add overhead to any device on which it is enabled.

Mesh Routing Initial Hop Limit
The Mesh Routing Initial Hop Limit specifies how close a device expects its target device to be when it starts
performing a route discovery.
Setting this value to zero indicates that the node expects its target node to be within direct radio range, which means
any other nodes in the vicinity who might overhear the route request will not attempt to assist with the initial route
discovery request, even if they do not have Mesh Override enabled.
Setting this to 1 instructs the SNAPlink device to send its route discovery requests in such a way that other nearby
nodes that do not have Mesh Override enabled will repeat the device's call for a mesh route, increasing the radio
chatter during the route discovery process.
In an environment where every node can directly communicate with every other node, zero is an appropriate setting.
However, in environments where direct communications may not always be possible, setting this to zero will
significantly increase the latency as the network will have to allow the first (unassisted) route request to time out
before sending a second route request with a broader appeal for assistance.
Mesh Reject LinkQuality Below
When establishing a mesh route, it is possible that a node may have inconsistent link quality with another node,
sometimes being able to reach it and other times encountering interference from the environment. It is possible,
then, for a node to establish a route where the link quality is at the fringes of what might be considered reliable.
In an environment like this, you can tell a node that it should require a certain standard of link quality (measured in
negative dBm) when performing route discovery.
The closer to the -100 dBm end of the scale, the more willing a node is to accept weak signals for its routes. The
closer you set a SNAPlink device to the -50 dBm end of scale a node is set to use, the stronger the radio signal it
requires for its route discovery process.
In an environment where every node can directly communicate reliably with every other node, changing this from its
default of -100 dBm serves no purpose.
WARNING: Adjusting these settings too far to the left or right can result in no communications getting through.
Multicast TTL (Master Setting)
The Multicast TTL setting is only meaningful in the context of master nodes in a point-to-multipoint configuration. It
specifies how many "hops" a message should be willing to take as it tries to find any willing listener. Each hop
represents an intermediate SNAPlink device that has heard the message from the master than then forwards it on to
others within range of it before acting on it.
For example, consider an environment where there are four SNAPlink devices in a long line: Master, Client1, Client2
and Client3. Assume the Master device's transmissions cannot get all the way to the farthest device, Client3; but it
appears Client1 could get it to Client2 and Client2 could get it to Client3 since each client is about a third of the
distance away from its neighbors. In this example, setting the Master TTL to 3 in the Master adapter, and setting
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Client 1 and Client 2 to On for the Multi-cast Forwarded Groups should help make sure all transmissions are received
by Client3. (Note that return messages from Client3 to the Master will also require that Client1 and Client2 have Mesh
Override disabled.)
In a point-to-multipoint environment where the master device can directly communicate reliably with all of the slaves,
the default value of 0 is appropriate. Setting the value higher will cause devices that do not have the Multi-Cast
Forwarded Groups feature disabled to unnecessarily forward the data packet, increasing radio chatter. In point-to-
point environments, this setting does not affect communications.
In a directly paired environment, this setting has no effect.
UART Tab
The UART tab contains three parameters for fine tuning data transmission. These can be set according to the needs
of the serial device. You may have to adjust them depending upon transmission speed and the size of data packets.
Buffering Timeout
This setting controls the overall serial data timeout. The value is in
milliseconds with the default being 0, indicating no timeout enforcement.
The Buffering Timeout controls the elapsed time between an initial
character being received and a packet of serial data being enqueued for
processing. When the timeout passes, regardless of the number of
characters buffered (other than zero) or the rate at which they are
received, the buffered data will be sent. The larger this value, the more
buffering that will take place. While this allows for more data to be sent per
packet, which might be more efficient depending upon your application, it
also increases latency.
Note that other events, controlled by Buffering Threshold and Inter-
character Timeout, can also trigger the buffer of data to be sent.
Buffering Threshold
This setting indicates the level where the SNAPlink device will decide that it has enough data to send a packet. If
data comes in faster than the threshold checks it is possible the packet size may be larger than the size specified.
The default is 100 bytes, and the maximum is 123 bytes. Values over 100 are not recommended as they could result
in buffer overrun.
Buffering Threshold causes buffered data to be sent whenever the threshold is reached. However, triggering the
Buffering Timeout or Inter-character Timeout settings could cause data to be sent before the threshold is reached.
Each packet of data includes a header, which comprises 12 bytes for multipoint packets and 15 bytes for point-to-
point packets. So, the actual number of data bytes sent will be either 12 or 15 bytes fewer.

If you set Buffering Threshold to a large number, then larger, more efficient packets will be sent, but with greater
latency. At higher bps rates setting this value too high can result in dropped characters, as the SNAPlink device may
receive more characters than it can fit in a packet before it has an opportunity to realize that the packet is full.
Inter-character Timeout
This setting allows you to tune the inter-character serial data timeout. This value is in milliseconds and defaults to 10.
Inter-character Timeout is the maximum elapsed time that should pass before sending the enqueued packet after
receiving a character. It restarts with every received character. This parameter can trigger transmission of buffered
data before Buffering Threshold is reached. Conversely, if the timeouts are high or disabled altogether, then data
will be transmitted when the Buffering Threshold is reached.
Setting a large Inter-character Timeout can give better reliability but with greater latency.
Pairing Tab
The Pairing tab indicates whether the SNAPlink device is paired with another device, which is denoted by displaying
the other device's SNAP address.
State
This is the paired state. The value can be:
lSimple Broadcast – Unit is in a reset state and is waiting
to be configured.
lSearching for Master – Unit is in multipoint mode and is
searching for a master unit to pair with..
lMaster – Unit is in multipoint mode and is the master. It is
now willing to accept slave units.
lSlave – Unit is in multipoint mode, is a slave, and has
paired with a master.
lReady to Pair – Unit is in point-to-point mode and is
looking for another unit to pair with.
lPaired – Unit is in point-to-point mode and has been paired
with another.
Address of Pair
When paired, this will be the last three bytes of the MAC address of the unit paired with this device. If a slave, this will
be the address of the master. If a master, this field will be blank.
Time Between Status Messages
SNAPlink devices will routinely ping paired partners to confirm that the connection remains valid. This ping
information is used for things like setting the color of the RF LED to indicate signal strength between nodes.
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This field specifies the number of seconds between pings. The default value is 3 seconds.
Advanced Tab
The Advanced tab contains a single checkbox labelled Button Lockout. When checked, the MODE button on the
front of the SNAPlink adapter will be disabled.
This means the pairing state or point-to-multipoint state of the device cannot be modified using the button.
However, the MODE button can still be used to perform a reset, putting the SNAPlink device back into broadcast
state. (After such a reset, the button will be enabled for pairing and configuration again.)

Configuring Your Adapter Using DIP Switches
If you do not have access to a computer running EasySet, you can configure some communication parameters using
the DIP switches located inside the unit.
Changing DIP switch settings will override the default
parameters, or parameters previously configured using
the EasySet software. However, EasySet can also
override the DIP switch settings from DIPswitch 1.
SNAPlink adapters have built-in intelligence to
determine if EasySet or the DIP switches were last used
to change the configuration. The general rule is: the last
method used to change the settings is the one that takes
precedence.
All SNAPlink models have a set of 8 internal switches
that set Flow Control, Bps Rate, and SNAP Channel.
The SL485 has a second set of 6 switches that configure
the device for either 2- wire or 4-wire operation, and to
specify whether the RS-485 or RS-422 standard should
be used.
To access the DIP switches, remove the screw adjacent to the serial connection (DE-9 connector or terminal block)
and lift the top of the enclosure off to expose the switches.
When you reassemble your device, the enclosure screw should be tightened to a torque of 0.5 to 0.9 Nm (4.4 to 8
inch pounds) for best results.
DIP Switch 1
DIP switch 1 is applicable to all SNAPlink devices. It has 8 individual switches, controlling the serial bps rate, flow
control, and SNAPradio channel.
Switch 1 controls flow control on SL232 devices. Move this switch "up" to the position labeled "ON" to enable flow
control. (Flow control is always enabled for SL485 devices.)
Switches 2, 3, and 4 collectively control the serial bps rate. There are eight speeds you can set with these switches.
Bps Rate Switch 2 Switch 3 Switch 4
300 On Off On
1,200 Off On On
2,400 On On On
9,600 Off Off Off
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