Autopilot and External Output (NMEA0183)

Choose "Data Output" when you want to output NMEA0183 data from TimeZero to an Autopilot or any External Display.

Each autopilot requires that certain, specific information be provided by TimeZero. Most autopilots follow the same basic principles of course to steer and cross track error. Autopilot tries to maintain a heading to a mark while maintaining a minimum Cross Track Error. TimeZero contains a number of specific settings that have been created because not all autopilots work the same way. Consult your autopilot manual to verify what information the device needs.

Output Configuration (NMEA0183)

TimeZero can output NMEA0183 data over a COM port (Serial or USB to Serial Adapter) or over an Ethernet network (using UDP or TCP). Select the appropriate option and click on Next:

Note: UDP is useful when you want to broadcast NMEA data to one or multiple computers located on the same local network (same broadcast domain). Use TCP if you need to route NMEA0183 data through the Internet or if the device or computer you are sending the data only accepts TCP connection. Note that when TimeZero is set to output NMEA data using a TCP port that was not previously configured as an input, it will create and open a TCP port and listen to incoming connection from a remote client (TimeZero becomes a TCP server). Just configure the client to connect to the server (TimeZero in this case) using its IP address and to the port that is configured on the next page.
If you would like to receive and send data on the same port over TCP (for example to receive and send data to a NMEA Multiplexer), first, start by configuring the TCP port as an input in TimeZero. Then, when configuring an output TCP port, you will be able to select the input port you previously configured, allowing TimeZero to send and receive data on the same TCP port.

The top of the output configuration window will automatically adjust according to the output mode (COM, UDP or TCP). In the example below, the serial (COM) output has been selected, allowing you to select a COM port and a baudrate (in case of UDP or TCP, you have to select a network adapter and a TCP/UDP port):

Note: If using a COM port and if the selected Port is already configured as an Input, you cannot select the Baudrate (it will be locked to the same baudrate as the input).

Note: The "Advanced" button is only reserved for Technical Support. Do not adjust any advanced settings yourself.

Once the port has been configured from the top of the page, select the NMEA0183 sentences you want to output from TimeZero to an External Device (including another TimeZero) or an Autopilot.

Most Autopilots only require "APB" and "XTE". If your pilot also needs position and speed information, add "RMC" to the list. It is recommended to read your Autopilot documentation to know what sentence you should select from the list.

IMPORTANT: Never send back position (RMC, GGA, GLL) to a device that already receives or outputs position. This can create a "data loop" and cause erratic behavior.

Note: When switching a Waypoint, TimeZero will always send an AAM (Waypoint Arrival Alarm) sentence to the Pilot. This allows the pilot to properly detect a switching Waypoint condition and notify you. If you want to trigger a notification inside TimeZero, make sure to check "Waypoint Switching Notification" and/or "End of Route Notification" from the Alarms Options.

Press "Next" to validate the settings then "Finish" to close the Wizard.

In order to confirm a good connection in between TimeZero and your Autopilot

  • Activate a route in TimeZero (or create an Active Waypoint using the "Go To" tool)

  • Add three Route NavData to the NavData panel in TimeZero: "CST", "DTW" and "XTE" (Please refer to the NavData chapter for more information)

  • Make sure that the Autopilot and TimeZero are using the same North reference (either "True" or "Magnetic"). You can adjust the North reference in TimeZero by adjusting the "Bearing Display" setting in the Units Options

  • Configure your pilot to show a "Steering Page" displaying at minimum the corresponding information:

    • Distance to Waypoint (usually labeled as "DTW" or "RNG" or "DIST")

    • Bearing to Waypoint (usually labeled "CST" or "BRG" or "Bearing")

    • Cross Track Error (usually labeled "XTE")

  • Confirm that the information displayed in TimeZero and on the pilot matches

If no information appears on the Autopilot ("--" for example), or if the pilot is not steering properly, check the Autopilot Troubleshooting chapter.

Advanced Output Settings:

NMEA Talker:

This setting changes the NMEA talker used in the NMEA sentence generated by TimeZero. The default is set to "II" ("integrated instruments"). Some older pilots or external displays might not recognize the "II" talker. In this case, try to change it to "GP".

APB:

This setting defines the North Reference that will be used inside the APB sentence for the Bearing to Waypoint (or CTS). Usually, if the Autopilots is connected to a Magnetic Heading sensor, you will use "Magnetic North". If the Autopilot is connected to a True Heading Sensor (such as a Satellite Compass), you will use "True North". If set to "Both", the APB sentences will alternatively use Magnetic and True North. If you choose either Magnetic or True North, it is usually recommended to set TimeZero with the same reference. You can adjust the North reference in TimeZero by adjusting the "Bearing Display" setting in the Units Options

MWV:

This setting defines the Wind Reference that will be used inside the MWV sentence. If set to "Both" the MWV sentence will alternatively use Apparent Wind and True Wind (angle & speed).

APB & HSC Heading to Steer:

The APB NMEA0183 sentence contains two bearing references: Course to Steer and Heading to Steer. When "Course to Steer" is selected in TimeZero, the Heading to Steer field inside the APB and HSC NMEA sentences will use the same value as the Course To Steer field (copy). If "Heading to Steer (real time)" is selected, TimeZero will apply the drift vector to the Course to Steer value to compute the proper Heading to Steer that takes into account the real time currents and use that value in the Heading to Steer field of the APB and HSC sentences. Note that for the Heading to Steer (real time) value to be correct, you need a high precision heading source (such as a Satellite Compass). For most application, it is recommended to leave this setting to "Course to Steer".

XTE:

The "Precision" settings indicate the number of digits used for the Cross Track field used in the NMEA sentences. Only decrease the precision if you have an old Autopilot that has trouble adjusting to high precision XTE.

The "ZEUS" mode is only to be used with ZEUS Mercury Autopilot. This setting alters the "end of route" behavior of TimeZero. When the ZEUS mode is selected, all the XTE fields are set to a NULL value (,,) when reaching the end of a route. For any other Autopilots, leave that setting uncheck.

DPT (Depth) Offset:

Indicates the type of transducer offset used in the NMEA Depth output. Make sure that the "Transducer Draft" and "Keel Draft" settings are properly setup in TimeZero from the Initial Setup Options.

TTM Bearing and Course:

Used to output the TTM bearing relative to own ship heading (relative) or relative to North.

To delete an output port:

  • Open the Connection Wizard

  • Select "Data Source" and press "Next"

  • Press "Next"

  • On the Master selection page. press the "Delete" button in front of the output port you want to delete

  • Press "Next" and "Finish" to close the Connection Wizard

 

Autopilot Output (NMEA2000)

When an Actisense NGT1-USB or NGX1-USB is connected to your computer and already setup as an input (NMEA2000 input), the last page of the Connection Wizard allows you to enable or disable the "NMEA2000 Pilot Output" (checked by default):

When "NMEA2000 Pilot Output" is checked, the following PGNs are automatically sent while a route is activated:

  • PGN 129283 - Cross Track Error

  • PGN 129284 - Navigation Data

  • PGN 129285 - Navigation Route/WPT Information (used to transmit the name of the destination waypoint)