Nmea Basics | Raymarine Marine GPS System instruction

RayTech Navigator User’s Guide

Basic NMEA and RS-232 Cabling Principles

This section explains some of the basic principles involved with National Marine Electronics Association (NMEA) and RS-232 electrical connections. Knowledge of this information is not required to connect Navigator to the various peripheral devices; however, it is provided for the advanced user as pertinent technical background.

NMEA Basics

Most marine electronic devices that output data do so over NMEA ports. NMEA ports are known as a “balanced pair,” which means that the data signal is carried over two wires (via an RS-422 electrical layer, in computer/datacom terminology). The signal level is determined by calculating the voltage difference between the two wires, hence the NMEA output signal is called a Differential Data Signal (not to be confused with Differential GPS, which is a GPS system error correction method).

Differential Data Signals are designed to be error-resistant by keeping the positive and negative leads close together for the entire cable run. This means that they both pick up the same levels of noise, which is ultimately subtracted from the signal, preserving the signal’s data integrity. NMEA ports typically have four connections (two for each lead): Transmit (positive/negative) and Receive (positive/negative). Some devices may use a single-direction port, meaning that they can transmit or receive only.

When connecting one NMEA device to another:

1.Connect Device A’s positive Transmit (Tx+) lead to Device B’s positive Receive (Rx+) lead.

2.Connect Device A’s negative Transmit (Tx-) lead to Device B’s negative Receive (Rx-) lead.

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Raymarine Marine GPS System manual Basic Nmea and RS-232 Cabling Principles, Nmea Basics

Contents

Distributed by Navigator Disclaimers and Warranty Guide Description Technical Accuracy Conventions Generall Conventtiions Telephone United States Telephone EuropeEmail Address Mailing AddressesPage Table of Contents Using Navigators Interface Customiiziing the Interface Working With Charts and Routes4-1 Measurriing Range and Bearriing Usiing VRM//EBL Usi ing Sonar Wi ith Navi igator Appendix a Connecting Peripheral Instruments Chapter Introduction Welcome to RayTech Navigator Easy Marine Navigation Using Routes and Waypoints Multiple Chart Formats for Flexibility Comprehensive Weather/Oceanographic Reporting Navigator’s Toolbars, Functionbars, and Databoxes Contour Display Optional Modules Sail Racer Module Fishing Pro Module Overview Before You Begin Minimum System Requirements Setting Your PC Monitor’s Colors for Best DisplayHardware Requirements To install Navigator from a CD Installing NavigatorInstalling From a CD InstallShield Wizard Welcome Screen InstallShield Wizard Customer Information Screen InstallShield Wizard Setup Type Screen ISW Custom Setup screen choices are defined as follows InstallShield Wizard Ready to Install Screen Installing From the Internet Chapter Using Navigator’s Interface Main Interface Component Descriptions Navigator’s Main Interface Waypoint Menu Drop-Down MenusFile Menu Route Menu Tools Menu Tools/Pre-Start Menu View Menu Window Menu Help Menu Waypoints and Routes Toolbar ToolbarsStandard Toolbar Charting Toolbar Alarm Toolbar Animation Toolbar Tides/Currents Toolbar View Toolbar Fishing Toolbar Weather Toolbar Yacht Racing ToolbarPre-Start Toolbar Standard Functionbar Functionbar MenusPathfinder Panel Toolbar 22. Standard Functionbar Menu Hierarchy Marks Button Route ButtonGoto Button Top-Level More Button Second-Level More Button File Button Weather Animation Button Setup Button Radar Functionbar 31. Radar Functionbar Menu Hierarchy Marpa Button Heading Mode ButtonTargets Button Gain Button 35. Radar Functionbar Gain Button Descriptions VRM/EBL Buttons 36. Radar Functionbar VRM/EBL Button Descriptions Sonar Functionbar Tune Button 38. Sonar Functionbar Menu Hierarchy Frequency Button Zoom Button Bottom Lock Button Scope Button 43. Sonar Functionbar VRM/EBL Button Descriptions Alarm Buttons 44. Sonar Functionbar Alarm Button Descriptions Using the Customize Dialog Box Customizing the Interface Commands Tab To customize drop-down menus To reset Toolbars to original default settings Toolbars TabTo display the Toolbars tab To create and name a custom Toolbar 46. Customize Dialog Box Toolbars Tab To associate keystrokes with commands Keyboard Tab Menu Tab 48. Customize Dialog Box Menu Tab Options Tab To display the Options tab Installing Charts About Using Charts with Navigator Where to Store Charts Installing MapTech PCX and NOAA/BSB Charts RayTech Settings Dialog Box Chart Installer Screen Chart Manager Screen 1 Showing Installed Charts Working With Routes Creating a Route To create and name a route Beginning a Route Completing a Route To add a waypoint to a route Editing Routes and WaypointsWaypoint Basics Adding, Moving, and Deleting 11. Edit Route Dialog Box Adding a Waypoint to a Route To move relocate a waypoint 12. Moving a Waypoint 13. Moving the Waypoint You Are Approaching To The Vessel To put a new waypoint at your vessel’s current position 15. Placing a Waypoint At The Vessel’s Current Position To put a new waypoint at the cursor’s current position 17. Placing a Waypoint At The Cursor’s Current Position 18. Placing a Man Overboard Marker To delete a waypoint from a route 19. Deleting a Waypoint To modify a waypoint’s display characteristics Modifying Waypoints Working With Charts And Routes Setting Relative Waypoints To set one waypoint as relative to another To temporarily set one waypoint to specific coordinates To return a waypoint to its relative coordinates Working With Waypoint Groups To create a new waypoint group To rename a waypoint group 22. Renaming a Waypoint Group To delete a waypoint group 23. Deleting a Waypoint Group To display or hide a waypoint group 24. Showing or Hiding a Waypoint Group Using the Waypoint Recycle Bin To retrieve waypoints from the recycle bin 26. Retrieving Waypoints From The Recycle Bin Using Radar With Navigator Chapter Advanced Navigator Functions RayTech Navigator User’s Guide To overlay radar data on top of a chart Displaying the Radar ScreenDisplaying the Top Line Status Header To display radar data in a separate window Displaying the Control Panel To display the Control Panel Using the Pathfinder Panel Toolbar Using the Range Control Changing the Range Standard Range Scale Radar Range Scales Determining Actual Radar Range Radar Range Interpreting and Adjusting the Radar Picture Controls to Adjust the Radar Picture Identifying False Echo Returns Side Lobes Indirect False Echoes Multiple Echoes Blind Sectors or Shadow Effect To adjust the Gain Radar Gain Control Sea Clutter Control Radar Sea Clutter Display To adjust Sea Clutter control Rain Clutter Control Radar Rain Clutter Display To adjust the Rain and FTC controls To tune the radar Tuning the ReceiverThat you leave the Tune control in Auto mode To change target mode settings Changing the Target Display Interference Rejection Target Expansion Measuring Range and Bearing Using VRM/EBL Target Wakes RayTech Navigator User’s Guide Using VRM/EBL To access VRM/EBLsMeasuring Range and Bearing to Target from Vessel Click To Move Click Moving a VRM/EBLTo move a VRM or EBL To place a mark symbol at the cursor position To place a mark symbol at the current vessel locationPlacing Marks To remove marks Safety Notices Introduction to Marpa Risk Assessment Target Data Target Vector and History Radar Range Scales Acquiring a Marpa Target To acquire a Marpa target To remove a target from the Marpa database Using the Marpa Dialog BoxDeleting a Marpa Target To acquire a target To clear a targetTo view target data the Marpa List To view selected target data in the Marpa box Using Sonar With Navigator To display sonar data in a separate Navigator window Pathfinder Panel for Sonar Fish Indications To display the depth of the fish Bottom Indications Effect of Frequency and Boat Speed Depth Target ID To toggle on and off the Target Depth ID To change the background color Selecting the Background ColorChanging the Scroll Speed To change the scrolling speed To pause the scrolling display Adjusting the Range Control To adjust the range and shift values Selecting the Frequency Selecting the Power SettingTo change the power setting Adjusting Display Gain Sensitivity To change the frequency Adjusting Color Gain To adjust the Color Gain To remove the A-Scope image Using the A-ScopeTo display the A-Scope image Using Bottom Lock To display the Bottom Lock image Using the White Line Using ZoomTo switch the white line feature on and off To use zoom Using Alarms Using VRM To set an alarm To use the VRM Using Waypoints To Place a Waypoint Using Polars to Optimize Your Performance 13. Typical Polars Plot Screen Collecting Data Entering and Editing Data Polar Parameters Screen 14. Polar Parameters Screen Advanced Navigator Functions Data Tests Screen 15. Data Tests Screen Advanced Navigator Functions RayTech Navigator User’s Guide ForestayStrain Displays only those tests that How to Graph and Read a Polar Plot To graph a Polar plot, do the following RayTech Navigator User’s Guide 18. Polar Plot Example Screen Using the Upwind, Downwind, and Vmc Plot Screens 19. Upwind Plot Screen 20. Downwind Plot Screen 21. Vmc Plot Screen Calibrating to Ensure Data Accuracy Boat Speed Calibration Compass Calibration Apparent Wind Angle Calibration True Wind Angle Calibration 22. Twa Corrections Screen True Wind Speed Calibration 23. Tws Corrections Screen Using the Engine Instrument Panel Displaying the Panel 24. Single Engine Instrument Panel with Tachometer Configuring the Panel 25. Engine Panel Settings Screen Showing Instruments Tab 26. Engine Panel Setting Screen Showing Panel Tab Appendix a Connecting Peripheral Instruments Connecting to Instruments Via an Nmea Cable Figure A-1. Raymarine Nmea Connection Cable, Part No. E86001 Connecting Directly to a GPS Table A-1. Connecting Navigator Directly to GPS System Connecting Directly to NMEA-Equipped Instruments Connect Cable Color To Nmea Instrument Lead Connecting Directly to Radar Table A-3. Connecting Navigator Directly to Radar System Connecting Directly an Autopilot Table A-4. Connecting Navigator Directly to Autopilot System Connecting Specific Instruments and Devices Connecting to a Raymarine Direct SeaTalk Interface Connecting to a Raytheon Autohelm System Figure A-1 and Table A-5 Table A-7. Connecting Navigator to a B&G Nmea FFD Display Connecting to B&G InstrumentsTable A-6. Connecting Navigator to a B&G Performance Board Connecting to KVH Instruments Table A-8. Connecting Navigator to a KVH Race Box Connecting to Ockam Instruments Basic Nmea and RS-232 Cabling Principles Nmea Basics RS-232 Basics RayTech Navigator User’s Guide Preventing Interference and Crosstalk Circuit Grounding IssuesProper Cable Shielding Connecting With a KiwiTech Cable Pin Serial Direct RayTech Navigator Version Raymarine Interim Sheet Click Save Now Click Send Now Create Route Charting Enhancements New Databoxes Other Vessel Tracking DataTrak Enhancements