SeaLevel SeaLINK.SC User manual

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© Sealevel Systems, Inc. 2123 Manual | SL9200 11/2021
SeaLINK.SC
User Manual | 2123

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© Sealevel Systems, Inc. 2123 Manual | SL9200 11/2021
Contents
CONTENTS............................................................................................................................................................................................................................2
INTRODUCTION...................................................................................................................................................................................................................3
BEFORE YOU GET STARTED..............................................................................................................................................................................................4
INSTALLATION & CONFIGURATION.................................................................................................................................................................................7
HARDWARE DESCRIPTION .............................................................................................................................................................................................14
SEALATCH™ USB .............................................................................................................................................................................................................15
ELECTRICAL SPECIFICATIONS ........................................................................................................................................................................................17
TECHNICAL SPECIFICATIONS.........................................................................................................................................................................................19
APPENDIX A –TROUBLESHOOTING.............................................................................................................................................................................20
APPENDIX B –HOW TO GET ASSISTANCE..................................................................................................................................................................24
APPENDIX C –ELECTRICAL INTERFACES....................................................................................................................................................................25
APPENDIX D –ASYNCHRONOUS COMMUNICATIONS.............................................................................................................................................26
APPENDIX E –CAD DRAWINGS - 2123.......................................................................................................................................................................27
APPENDIX F –COMPLIANCE NOTICES.........................................................................................................................................................................28
WARRANTY ........................................................................................................................................................................................................................29

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Introduction
Overview
Sealevel’s SeaLINK® 2123 USB to serial interface adapter offers an easy way to connect a DB9 serial device
to a USB port. All configuration and electrical interface selections are handled through the driver,
eliminating the need to open the enclosure to set jumpers or switches. The serial port is software
configurable for RS-232, RS422, or RS-485 (full and half duplex) with the electrical interface settings
maintained locally, allowing the host computer to be repaired or upgraded without reconfiguring the serial
ports. Additionally, the 2123 can be configured at one computer and deployed to other computers.
Sealevel SeaCOM USB software drivers and utilities make installation and operation easy for Windows 98SE,
ME, 2000, XP, and Vista operating systems. Once the software is installed, plug the 2123 into an available
USB port and the serial port is recognized as a standard COM port by the host system enabling compatibility
with legacy software. Serial data rates to 921.6K bps are supported.
To prevent accidental cable disconnection, the 2123 integrates a patent-pending SeaLATCH locking USB
port, which is fully compatible with standard USB cables. When used with the included USB cable with a
SeaLATCH USB type B connector, the metal thumbscrew provides a secure connection to the device.
Standard operating temperature range is 0°C to 70°C and extended temperature range (-40°C to +85°C) is
optional. Status LEDs display electrical interface selection and serial data activity.
Features
Serial port is software configurable for RS-232, RS-422, and two-wire or four-wire RS-485
Electrical interface settings maintained across multiple computers
High speed UART with 128-byte Tx FIFO and 384-byte Rx FIFO
Automatic hardware RS-485 enable/disable
DB9M connector –serial port supports data rates to 921.6K bps
Powered by USB host connection
Full modem control signals implemented in RS-232 mode
Status LEDs indicate power, electrical interface, and serial data activity
Flexible mounting options
DIN rail clips are available as an option.

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Before You Get Started
The SeaLINK.SC is shipped with the following items. If any of these items is missing or damaged, please
contact Sealevel for replacement.
•2123 –USB to RS-232/422/485 Two Port Serial Interface Adapter
•CA356 –USB Type A to SeaLATCH USB Type B Device Cable, 6’ in Length
Advisory Conventions
Warning
The highest level of importance used to stress a condition where damage could result to the
product, or the user could suffer serious injury.
Important
The middle level of importance used to highlight information that might not seem obvious or a
situation that could cause the product to fail.
Note
The lowest level of importance used to provide background information, additional tips, or other
non-critical facts that will not affect the use of the product.

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Optional Items
Depending upon your application, you are likely to find one or more of the following items useful. All items
can be purchased from our website (www.sealevel.com) or by calling our sales team at [phone].
Cables
DB9F to DB25M (RS-232) Extension Cable (Item# CA177)
The CA177 is a standard AT-style RS-232 modem cable
with a DB9F connector on one end and a DB25M
connector on the other. This cable is 72 inches length.
DB9F to DB9M Extension Cable (Item# CA127)
The CA127 allows users to extend a DB9 cable up to six
feet. The connectors are pinned one -to-one so the cable
is compatible with any device or cable that has DB9
connectors.
DB9F (RS-422) to DB25M (RS-530) Cable (Item#
CA176)
The CA176 allows users to convert any Sealevel
RS- 422 DB9 Male asynchronous adapter to an
RS-530. DB25 Male pinout. This cable is ten
inches in length.

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Terminal Blocks
Terminal Block –DB9F to 9 Screw Terminals (Item# TB05)
Terminal Block –DB9F to 9 Screw Terminals (Item#
TB05) The CA127 allows users to extend a DB9 cable up
to six feet. The connectors are pinned one -to-one so the
cable is compatible with any device or cable that has DB9
connectors.
Terminal Block –Dual DB9F to 18 Screw Terminals (Item# TB06)
The TB06 terminal block breaks out dual DB9 connectors
to 18 screw terminals to simplify field wiring of serial
connections including RS-422 and RS-485 networks. The
TB06 is designed to connect directly to Sealevel dual port
DB9 serial cards or any cable with DB9M connectors.
Adapters and Converters
DB9F to RJ45 Modular Adapter (Item# RJ9S8)
The RJ9S8 is a DB9 female to RJ45 adapter. It can be
configured without tools, and it is an excellent choice for
using available infrastructure wiring.

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Installation & Configuration
Software Installation
Windows 98/ME/2000/XP/Vista™ Operating Systems
1. Begin by locating, selecting, and installing the correct software from the Sealevel software
driver database.
2. Select the Part Number (2123) for your device from the listing.
3. Click the ‘Download Now’ button. The SeaCOM software is available for Windows and Linux.
4. The setup file will automatically detect the operating environment and install the proper
components.
To confirm that the SeaCOM driver has been successfully installed, click on the ‘Start’ button, and then
select ‘All Programs.’ You should see the ‘SeaCOM’ program folder listed.
You are now ready to proceed with connecting the 2123 to your system. Refer to the Hardware
Installation section for details.
Windows NT is not USB aware and thus cannot support this device.

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Hardware Installation
Do not connect the device to a USB port until the software has been successfully installed.
To install the 2123, plug the device into an available USB port using the supplied USB cable. The following
instructions were tested with Windows XP and may vary based on your version of Windows.
Once the device has been connected, the Found New Hardware wizard will appear first for the root hub and
then for each port that you are installing. Follow the instructions on the following page to finish installation.
The installation will repeat twice for the COM port. This is a limitation in the way Windows installs
external serial devices.
1. Click on ‘Install the software automatically’ followed by the ‘Next’ button.
2. Windows will show a warning message that the hardware has not passed Windows
logo testing. Click on ‘Continue Anyway.’
3. Click on ‘Finish.’
All applications and drivers have been fully tested to maintain the integrity of your operating
system. Clicking on ‘Continue anyway’ will not harm your system in any way.
Verifying Installation
To confirm that the drivers have been successfully installed, you can look in Device Manager under ‘Ports
(COM & LPT)’ and the port you installed will be included on the list with the associated COM number. To
access Device Manager, follow the steps below:
1. Right-click on the ‘My Computer’ icon on your desktop or in the Start menu.
2. Click on ‘Properties’ in the fly out menu to launch the ‘System Properties’ window.
3. Click on the ‘Hardware’ tab and then click on the ‘Device Manager’ button.
4. When Device Manager launches, look under ‘Ports (COM & LPT)’ to verify that the serial port has
been correctly installed (screenshot of 2833 shown; only one port will be listed for the 2123).

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Your system will assign the next available COM numbers which may vary for each computer used.

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Hardware Configuration
Electrical Interface Mode Selection
The 2123 offers RS-232, RS-422, and RS-485 (full and half duplex) modes. The electrical interface is a
software selectable feature that can be accessed and changed using the Sealevel SeaCOM driver via Device
Manager. To select the electrical interface, follow the steps below:
1. Open Device Manager and locate ‘Ports (COM&LPT)’ following the steps above. You should see
the 2123’s port listed.
2. Select the port by right-clicking on it and selecting ‘Properties’ from the fly out menu. The serial
port properties menu will appear.
3. Click on the ‘Interface Settings’ tab (screenshot of 2833 shown).
The Sealevel SeaCOM driver adds the ‘Interface Settings’ tab. If this tab is missing, SeaCOM is not
correctly installed.

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Hardware Configuration, Continued
4. Select the appropriate electrical interface for your application and click on ‘OK.’
The electrical interface settings are maintained across multiple computers. Once the SeaCOM
software driver has been installed on target computers, the 2123 can easily be moved from one
computer to another without having to configure the electrical interface at each computer.
lnterface Biasing
1K-ohm pull up/pull down combination resistors bias the receiver inputs and are handled automatically
for each mode. The pull-up (PU) and pull-down (PD) resistor settings are shown in the table below.
Mode
PU Setting
PD Setting
RS-232
Always Off
Always Off
RS-422
Always Off
Always Off
RS-485
Always On
Always On
Line Termination
A 120-ohm resistor is across the RS-422/485 input. If multiple devices are configured in an RS-485 network,
only the devices on each end should have the termination in place.
Termination configuration is software selectable for both full- and half-duplex RS485. By default, line
termination is disabled, and this configuration can be set by placing a check next to ‘Enable Termination’ in
the ‘RS-485 Advanced Configuration’ field, as shown in the image below.

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Hardware Configuration, Continued
Line Termination

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Hardware Configuration, Continued
Echo
The RS-485 ‘Echo’ is the result of connecting the receiver inputs to the transmitter outputs. Each time a
character is transmitted; it is also received. This can be beneficial if the software can handle echoing (i.e.,
using received characters to throttle the transmitter), but it can also confuse the system if the software
cannot support echoing.
Echo configuration is software selectable for half-duplex RS-485. By default, ECHO is disabled, and this
configuration can be set by placing a check next to ‘Enable Echo’ in the ‘RS-485 Advanced Configuration’
field, as pictured below.

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Hardware Description
SeaLATCH™ USB Port
The 2123 integrates a patent-pending SeaLATCH USB port, which is fully compatible with standard USB
cables. When used with the included USB cable with a SeaLATCH type B USB connector, the metal
thumbscrew provides a secure metal-to-metal connection to the device and prevents accidental cable
disconnection.
Status LEDs
Status LEDs on the front of the 2123 indicate the following information:
oMODE (Red or Green) –Indicates the electrical interface selected o Green indicates RS-232
mode o Red indicates RS-422 or RS-485 mode
oDATA (Green) –Blinks to indicate data is being transmitted or received
oEN[able] (Green) –Lights when the hub is properly powered through the
USB port and communication between the device and host has been enabled
DB9M Serial Connectors
The 2123 includes a single DB9M serial connector with full modem control signals implemented in RS-232
mode. Pin outs for the connector are included in the following Electrical Specifications section.

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SeaLATCH™ USB
The 2123 integrates a patent-pending SeaLATCH USB port, which is fully compatible with standard USB
cables. When used with SeaLATCH locking USB cables, the metal thumbscrew provides a secure metal-to-
metal connection and prevents accidental cable disconnection.
Sealevel incorporates SeaLATCH locking USB ports on many USB I/O devices. Accidental cable
disconnection is the most common point of failure with USB industrial I/O devices and SeaLATCH cables
and connectors prevents that while being fully compatible with standard USB cables.
The image below shows the 2123 secured with the included SeaLATCH cable.

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SeaLATCH Locking USB Cables / SeaLATCH USB Connectors
SeaLATCH locking USB cables integrate a small thumbscrew into each USB connector.
SeaLATCH USB Connectors
SeaLATCH USB cables are fully interchangeable with
standard USB cables. The thumbscrew provides a
secure metal-to-metal connection preventing accidental
disconnection. SeaLATCH USB cables are available in
three configurations.
72” USB Cable with SeaLATCH type B connector and a standard USB type A connector (Item# CA356)
The CA356 is a 72” USB cable with a SeaLATCH type B
connector and a standard USB type A connector. This
cable provides a secure connection between Sealevel
products with a SeaLATCH type B port and legacy USB
type A ports. The CA356 is included with Sealevel
devices with a SeaLATCH type B port.
72” USB cable with both SeaLATCH Type A and B connectors (Item# CA332)
The CA332 is a 72” cable with both SeaLATCH type A
and B connectors. This cable secures both ends of the
cable to devices with SeaLATCH USB ports and offers
complete protection against accidental cable
disconnection.
72” Cable with standard USB type B and SeaLATCH type A connector (Item# CA355)
The CA355 is a 72” cable with a standard USB type B
and a SeaLATCH type A connector. This cable provides
a secure connection between legacy USB devices and
Sealevel products with a SeaLATCH type A port, such as
the isolated USB hub (Item# 270U).

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Electrical Specifications
The 2123 connects to a single USB port and provides a single RS-232/422/485 software configurable serial
port. The 2123 utilizes high speed USB/UARTs with 128-byte Tx FIFOs and 384-byte Rx FIFOs. The chips
feature programmable baud rates and data rates to 921.6K bps.
Connector Pinouts
RS-232 (DB9 Male)
Pin #
Signal
1
DCD
2
RX
3
TX
4
DTR
5
GND
6
DSR
7
RTS
8
CTS
9
RI
RS-422 & RS-485 Four-Wire (DB9 Male)
Pin #
Signal
1
RX+
2
RX-
3
TX-
4
TX+
5
GND
Pins 6 –9 are “no connect’

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Electrical Specifications, Continued
RS-485 Two-Wire (DB9 Male)
Pin #
Signal
3
DATA-
4
DATA+
5
GND
Pins 1, 2, 6-9 are ‘no connect’

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Technical Specifications
Physical Dimensions
Package Length
4.3 inches (10.9 cm)
Package Width *
3.4 inches (8.6 cm)
Package Height
1.3 inches (3.3 cm)
Environmental Specifications
Specification
Operating
Storage
Temperature Range
0º to 70º C (32°F –158°F)
-50º to 105º C (-58°F –221°F)
Humidity Range
10 to 90% R.H. Non-Condensing
10 to 90% R.H. Non-Condensing
Power Requirements
This device is a high power USB device. It must be plugged directly into a USB port on your computer or a
self-powered hub capable of supplying 200 mA per port. Some laptop computers running on battery power
and non-powered USB hubs may not provide the 200mA necessary to power this device.
Manufacturing
All Sealevel Systems Printed Circuit boards are built to UL 94V0 rating and are 100% electrically tested.
These printed circuit boards are solder mask over bare copper or solder mask over tin nickel.

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Appendix A –Troubleshooting
The adapter should provide years of trouble-free service. However, in the event that it appears to be
functioning incorrectly, the following tips can eliminate most common problems without the need to call
Technical Support.
1. Ensure that the Sealevel Systems SeaCOM software has been installed on the machine so that
the necessary files are in place to complete the installation. To confirm installation, click on the
Windows ‘Start’ button and then select ‘All Programs.’ You should see the ‘SeaCOM’ program
folder listed.
The SeaCOM driver must be installed before the adapter is connected to your computer.
2. Check to make sure that USB support is enabled and functioning properly in the operating system.
The presence of the ‘Universal Serial Bus controllers’ listing in Device Manager will confirm that
USB support is enabled in Windows 98SE, ME, 2000, XP, or Vista operating systems.
3. While Device Manager is open, locate the COM ports (described under “Verifying Installation” in the
Installation and Configuration section of this manual).
4. Once you have confirmed that the COM ports are listed in Device Manager, you can use the Sealevel
WinSSD utility, and a loopback plug to test communications. Detailed help is included in the
WinSSD utility.
oIf you have a loopback plug, put it on the DB9 connector that you want to test. If you do not
have a loopback plug, contact Technical Support for assistance.
oIf you are testing RS-485 mode, you will need to have ECHO enabled otherwise the
following test will fail. Refer to the Hardware Configuration section for instructions on
enabling ECHO.
oTo test communications, launch the WinSSD utility in the SeaCOM folder under the ‘Start’
menu.