Brookhouse NMEA 0183 multiplexer setup.

The setup procedure is only required if one or more of the special functions of the multiplexer need to be activated. In many cases the multiplexer can be used "out of the box", without any optional settings. The setup procedure does not necessarily have to be executed on board the vessel. As only 12V DC  power and a computer connection are required, the setup can be done anywhere. However, for more complicated installations whereby perhaps different settings have to be tried out and scripts have to be uploaded, a permanently wired on-board computer connection is advantageous.  

Multiplexer models with AIS and USB

A computer with Windows XP and terminal program Hyperterminal is assumed because this is the most common. Other terminal programs can be used instead. For the MAC, program ZTERM is a suitable terminal program. Note that a multiplexer with USB does not have to be set up via a USB connection, only if the computer  has no other than USB ports. If an RS232 port is available, all multiplexers, with or without USB, can be set up via an RS232 link. Setup through USB is assumed from here on.

  1. The blue wire has to be inserted as shown in the picture. This makes computer output to the multiplexer via USB possible.



  2. Plug the multiplexer USB cable in a free computer USB port. The multiplexer does not have to be powered on at this stage, because USB power is supplied by the computer USB port. If Windows detects "new hardware" and no suitable driver is found, first follow the driver installation procedure.
  3. Check in Windows Device manager which virtual COM port has been assigned. If the Brookhouse supplied driver for XP has been installed, the COM port will show as follows:





    The Brookhouse mux USB is based on the Prolific chipset. If there is already a suitable driver available, the multiplexer com port may show up as follows:





    To make sure that this is the multiplexer COM port if other USB devices are also connected, unplug and plug back in the multiplexer while observing the device manager window.
  4. Start Hyperterminal. The following screen will appear:




  5. Enter a name for the connection. It is useful to choose a descriptive name if you want to save the Hyperterminal setup for later use.
  6. Click OK, the following window will appear:





  7. In the "Connect using" menu, select the COM port that you found in step 3.
  8. Click OK, the following window will appear:




  9. Select the settings as indicated.
  10. Click OK. This completes the required basic settings for Hyperterminal. The main Hyperterminal screen is now displayed. If you intend to upload a script to the multiplexer later, it is useful to change one other setting. If not, skip to step 13.
    Click on "File" at the top left corner of the Hyperterminal screen and choose "Properties" from the menu. The following window will appear:




  11. Click on ASCII Setup. The following window will appear:



  12. Tick "Send line ends with line feeds". The purpose of this is that when you upload a script later on, each line is displayed.
  13. Click OK, click OK again, you are now back on the main Hyperterminal screen. Communication with the multiplexer for the setup can now commence.
  14. Prepare for tapping the ESC or / (forward slash) key.
  15. Apply power to the multiplexer. The red light will turn on and the green light will flash 3 times to indicate start-up. Tap the ESC or /-key during the start-up phase, i.e at any time before the green led has flashed for the 3rd time. The following menu, sent by the multiplexer, will appear on the Hyperterminal screen:





  16. At this point multiplexer options can be selected. Menu selections can be made by entering a single digit or letter. Do not press the Enter key after entering the code. If the required function is selected by a letter, it has to be upper case. Therefore, for convenience, press the "Caps Lock" key on the keyboard first. We'll proceed with an example: Typically for AIS multiplexers, often a baudrate conversion option is required. Read the page that describes Baudrate Conversion Options first, before entering your selection. Let's assume you have determined that baudrate conversion option 2 with channel block mask E is required. This option is selected by entering 6, not by entering 2. The latter would change the baudrate to 9600. Press 6 and the multiplexer will respond with "6 selected, enter channel block mask". Now enter E and the multiplexer will respond with "E selected, press ESC to continue: "  Never press the Enter key for channel block mask. It has to be a valid code.  The bottom of the screen now looks as follows:




  17. The selection of the option is now complete. By pressing ESC, the menu is displayed again as in step 15 and the multiplexer is ready for selection of the next option. Let's assume you also want to upload a script. The script in the example  is a typical script, often used for AIS transponders. It programs the mux to use the GPS of the transponder as a backup if the GPS on input port 1 stops. It also cleans the transponder output data stream by removing !AIVDO and proprietry sentences. The script has been prepared and is stored as a text file with the name ais_xponder_script in a folder mux_script_files on the F-drive. To upload the script, select option F from the menu. The Hyperterminal screen now looks as follows:






    Click on Transfer at the top of the Hyperterminal window and select Send text file. The following window appears:




  18. Navigate to the folder containing the script to be uploaded. Select the script file ais_xponder_script (the only one in this case) and click on Open. This will start the upload to the multiplexer. After completion, the screen looks as follows:






  19. After pressing ESC the multiplexer is ready for the next menu selection, etc.
  20. If the letter X is selected, no confirmation is given as with the other options. The multiplexer leaves setup mode, resets and starts normal operation mode. Entering X is equivalent to turning the power off and re-starting the mux.

Setup for standard multiplexer model with USB

The set up procedure is the same as described above for AIS models, with 2 exceptions:

  1. The baudrate in Hyperterminal has to be set to 4800 for the first time setup. If the baudrate is changed to another value, next time a setup is done, the new baudrate has to be set in Hyperterminal.
  2. The setup menu is different.

Setup using RS232

For AIS models and the standard model multiplexer. 

The same procedures as for setup via USB apply, see above, but steps relating to USB can be skipped. For multiplexers with USB, the blue wire (step 1 above) should not be connected for setup via RS232.