USB to Serial Gateway User Manual USG-1-B-422 For use with NMEA 0183 and IEC 61162-1 connections Issue 1.04 Create a safe serial port connection to an NMEA 0183 system that may be on a different power circuit.
USB to Serial Gateway - USG-1-B-422 Contents Important Notices Notices Foreword Introduction USG-1 solutions 4 4 4 4 5 Features Software updates NMEA 0183 interfacing The basics 5 5 6 6 Opening the USG-1 USG-1 connections Connecting NMEA 0183 devices 6 7 8 Solution #1 - Ground loops Solution #2 - Different standards Solution #3 - PC has no serial port The NMEA signals The different NMEA standards NMEA 0183 Input NMEA 0183 (ISO-Drive) Output 5 5 5 6 6 8 8 Connecting to a Personal Computer RS232
Important Notices Foreword Actisense and the Actisense logo are registered trademarks of Active Research Limited. All rights are reserved. The contents of this manual may not be transferred or copied without the expressed written permission of Active Research Limited. All other trademarks are the property of their respective owners. Actisense recognises that instructions are often skipped, so we have aimed to write this document in an informative, yet direct manner that will aid the user.
USB to Serial Gateway - USG-1-B-422 USG-1 solutions Solution #1 - Ground loops The first problem encountered when using a standard USB to serial converter (or a standard RS232 port) is that the ground of the PC is then shared with the NMEA 0183 system ground. PCs are often powered from a mains inverter, generator set or direct from mains supply when in dock, whereas the marine electronics are normally connected to the current marine battery set.
NMEA 0183 interfacing The basics NMEA data is transmitted from an information source such as GPS, depth sounder, gyro compass etc. These data sending devices are called “Talkers”. Equipment receiving this information such as a chartplotter, radar or NMEA display is called a “Listener”. Unfortunately, only one Talker can be connected on to a single NMEA 0183 system at any one time.
USB to Serial Gateway - USG-1-B-422 USG-1 connections 5 4 1 2 3 Figure 1 – Inside the USG-1 case Figure 1 shows an internal view of the USG-1 Printed Circuit Board (PCB). The USG-1 has screw-terminal “Phoenix” type connectors with a pre-installed cable. The Phoenix-style connectors are provided for use when the customer needs to use their own cable. 1 2 1. An NMEA 0183 input. Two screw-terminal Phoenix-style connectors are provided to connect the NMEA 0183 input.
Connecting NMEA 0183 devices B/-/GND A/+/TX NMEA Talker B/-/GND A/+/RX NMEA Listener Do not connect Figure 2 – NMEA 0183 connections NMEA 0183 Input The NMEA 0183 differential Opto-isolated input is designed to handle a variety of NMEA 0183 device output specifications. The user must determine (from device manufacturer’s information) if the device(s) required to be connected to the Actisense USG-1 conforms in full to the NMEA 0183 network communication standard.
USB to Serial Gateway - USG-1-B-422 Connecting to a Personal Computer RS232 port TX Pin 3 RX Pin 2 Do not connect GND Personal Computer ( 9 PIN 'D' RS232 Port) Pin 5 Figure 3 – Personal Computer / RS232 port connections The USG-1 can be connected to a PC communications port using a cable conforming to the following specification: 1. A D-type female (socket) connector for the PC end of the cable 2. A minimum of 3-cores are required in a shielded cable.
USB Driver Installation The Actisense USG-1 makes use of a virtual serial port driver (know as the Virtual COM Port Driver) to interface between the USB port on the PC and the Actisense product. This driver allows software running on a PC to communicate with the Actisense USG-1 as if it was connected to a standard serial port on the PC, when in fact all communication is done over the USB connection. Step by step guide 1. Make sure the Actisense USG-1 is connected to an available USB port on the PC.
USB to Serial Gateway - USG-1-B-422 3. Make sure the ‘Include this location in the search’ option is ticked, and use the ‘Browse’ button to locate the ‘USB Drivers’ directory on the Actisense CD. 5. The ‘USB Serial Converter’ driver is now installed, click ‘Finish’ to complete the wizard, and wait for the ‘Found New Hardware Wizard’ to appear again. 4.
USB Configuration To communicate with the USG-1, the COM port number that Windows has allocated to the USB port needs to be determined. The following guide will walk the user through this standard operation. Step by step guide 1. Make sure the Actisense USG-1 is connected to an available USB port on the PC. From the Windows ‘Control Panel’, open the ‘System Properties’ window and click on the ‘Hardware’ tab.
USB to Serial Gateway - USG-1-B-422 3. Double click on the port icon for the ‘Actisense USG’ and the port properties window will appear. Click on the ‘Port Settings’ tab. Here you can set the default settings for the USG-1 device. It is not necessary to change the default settings here - as each software program will define these settings itself. 4. Click on the ‘Advanced’ button and choose a different COM Port number if required (to make it compatible with the software requiring the USG-1 NMEA data).
Troubleshooting guide This guide will concentrate on all relevant troubleshooting issues above simple cable connection faults. Therefore, the cables between the USG-1 hardware and any other devices should be checked as a matter of course, before continuing with this guide. Diagnostic LED The USG-1 hardware has a bright LED that can be seen through the case to indicate when data is either received or transmitted. It can be used to debug potential problems.
USB to Serial Gateway - USG-1-B-422 Specifications The USG-1 ISO-Drive output is a very flexible output that is RS485, RS232, RS422 and NMEA 0183 compatible. Parameter Conditions Min. Max. Unit From USB port 4.75 5.25 V Supply voltage = 5v (no load) 40 46 mA Supply voltage = 5v (output shorted) 75 80 mA -15.0 0.5 V 4.0 15.0 V 2.0 9.0 mA 1.8 2.
Order codes: USG-1-422 USG-1-485 USG-1 for use with NMEA 0183 and RS422 interfaces USG-1 for use with RS485 industrial interfaces Company Information Active Research Limited 5, Wessex Trade Centre Ringwood Road Poole Dorset UK BH12 3PF Telephone: Fax: 01202 746682 (International : +44 1202 746682) 01202 746683 (International : +44 1202 746683) Actisense on the Web: For advice, support and product details E-mail: Website: support@actisense.com www.actisense.
