Bidirectional Multiplexer

Discussion and support for the Nmea2Wifi multiplexer
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Luis Sa
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Posts: 61
Joined: Thu May 04, 2017 4:12 am

Bidirectional Multiplexer

Post by Luis Sa » Tue Sep 12, 2017 11:19 pm

Hello,

I am releasing firmware version 4.0 of the NMEA2WIFI multiplexer. In this version you can:

1) Send through the serial output port data received by wifi. With this facility you can, for example, control your autopilot using your smartphone

2) Select the data streams that pass through the multiplexer. For example, you can choose serial input port 1 or serial port 2 or both to be transmitted through wifi. Also you select what is output on serial port P#3 (any combination of inputs P#1, P#2 or Wifi). In version 3.0 you only had the options of: Serial Out = ON or OFF; Wifi Out = ON or OFF

If you do not need any of these improvements, you should go on with version 3.0. If you want to try this new firmware you should download the file NMEA2WIFIV40.bin and use the method explained in the previous post of this forum.

When this new firmware is fully tested, new units will be dispatched with it. You can see here the user settings page for the new version.

Note: I released NMEA2WIFIV41.bin which version 4.1 of the firmware. If you have version 4.0 you do not need this new version unless you need to test the operation of the Nmea 183 serial ports as described here.

Regards, Luis

zigakusar
Posts: 1
Joined: Tue Sep 05, 2017 4:41 am

Re: Bidirectional Multiplexer

Post by zigakusar » Tue Oct 03, 2017 8:42 pm

I have made extensive test with new firmware. First at my home with electronic used on my sailboat, and then also at sea.
My setup is:
- NMEA2WIFI (nmea to wifi converter)
- Daisy AIS (AIS receiver, connected via RS-232 TTL built-in interface to NMEA2WIFI on P2)
- Humminbird Matrix 17 with GPS (Fishfinder with serial GPS receiver, connected via RS-232 interfaceto NMEA2WIFI on P1)
- Raymarine ST1000+ autopilot (NMEA autopilot, connected via RS-232 interface to NMEA2WIFI on P3)
- OpenCPN on android smartphone

I have left home test running couple of times. The longest test takes 2 complete days. And I didn't found any issue. The system was stable and reliable all the time.
I have also run a test on my sailboat. Duration of this test was 2 hours without any problem.

With NMEA2WIFI I have advantages:
- Now I have redundancy. If my GPS connected to Fishfinder stop working, I can use GPS on my smartphone.
- If navigation on my Fishfinder stop working, I can drive autopilot from Open CPN on android smartphone.
- If the weather is bad, I have all essential data on my smartphone too.
- I can use andhor alarm and AIS radar on smartphone - that is not supported on my Humminbird.

JohnH
Posts: 3
Joined: Tue Jan 02, 2018 6:19 pm

Re: Bidirectional Multiplexer

Post by JohnH » Wed Jan 03, 2018 3:56 pm

I am delighted with this device, and have tried the test mode and accessing via a tablet, though with no data.

Before visiting the boat and connecting to existing instrumentation (Raymarine, very like the schematic depicted in the SeaTalk-NG topic), it would be useful to have simulated data for testing the setup with a WiFi client device.
Is there any chance you could add a test mode with simulated transmission of one or more parameters such as Depth?
This would allow testing with the Navionics Boating app over WiFi connection.
Or can you suggest simulation software and a simple adapter circuit for a PC with serial port?

For your information I also use Marine Navigator on an Android device, and hope to view live AIS data in future - in the meantime I'm happy with your recommendation of SeaWi which seems very useful except for the basic charts.

Luis Sa
Site Admin
Posts: 61
Joined: Thu May 04, 2017 4:12 am

Re: Bidirectional Multiplexer

Post by Luis Sa » Sat Jan 06, 2018 5:33 pm

Hello John,

Thank you for the suggestion which is most appreciated. Yes it can be done as it is only software. The easier way for me to do that is to add a check box in the main (and single) web page interface . It could be called "Simulation Mode". If the box is checked, the multiplexer would ignore the 2 Nmea 183 entry ports and the wifi UDP receiving ports independently of these particular settings. Instead it would read from its EPROM memory preloaded Nmea 183 sentences and would transmit them through the wifi port at a predefined (and fixed) rate.

If you or someone reading this wants to supply me a set of Nmea sentences (may one for GPS position, one for depth, one for wind speed and direction, one for temperature and two or three for AIS vessels) I could integrate this future in a new firmware version.

Best Regards, Luis

JohnH
Posts: 3
Joined: Tue Jan 02, 2018 6:19 pm

Re: Bidirectional Multiplexer

Post by JohnH » Tue Jan 16, 2018 7:10 pm

Hello Luis, thank you for your quick and constructive reply.

I was going to suggest that a quick and easy solution might be to copy SeaWi's Simulation data file that, according to the documentation, is "..... stored in folder SeaWi/SimLog of your phone or tablet" - though you may have to consider copyright?

Then I realised it should be easy to send simulated data from a PC serial port (actually via a USB to serial converter), wiring the 9-pin connector according to https://goo.gl/images/m2vRuf to port A (at 4800 baud) on the NMEA2WIFI device.

I tried several NMEA simulation programs from http://www.sailsoft.nl/nmea_simulator.html:
- NmeaFileReader Software to play a previously recorded log file from a Raymarine AIS500 that included sentences for Position/SOG/COG and AIS reports of several neighbouring vessels.
- GPSSimul (free limited version): simulates basic GPS data
- NemaStudio (free limited version): simulates GPS data as well as several other instruments - notably depth

I was able to view the data successfully using applications as follows:
- Packet Sender on PC: Initial test following your useful tip in post "Using the NMEA2WIFI multiplexer to test a talker!"
- SeaWi on Android Mobile: displayed Position/SOG/COG correctly, and also depth

I also tried several navigation programs with mixed results (perhaps due to incorrect setup), using data recorded from a Raymarine log:
- OpenCPN on PC: displayed Position/SOG/COG correctly, but not AIS targets
- OpenCPN on Android tablet (with internal GPS disabled): no data, which suggests that the Android version is not yet fully functional.
- Marine Navigator on Android mobile phone (with internal GPS disabled): no data, which suggests that it needs the internal GPS, and that the current AIS demo mode is not yet functional
- Navionics Boating on Android tablet (with internal GPS disabled): displayed both Position/SOG/COG correctly, and also depth - though you have to be careful to disable uploads to their "Community Edits" server!

The latter two Apps are the ones I use in the cockpit, to complement the Plotter in the cabin.

With confidence based on bench testing, I finally installed your device on the boat and it works perfectly with the SeaWi App on my Android mobile - so I'm very happy with my purchase!

And perhaps it's not worth bothering with a simulation mode.

Many thanks! Kind regards, John

Luis Sa
Site Admin
Posts: 61
Joined: Thu May 04, 2017 4:12 am

Re: Bidirectional Multiplexer

Post by Luis Sa » Fri Jan 19, 2018 5:01 am

Hello John,

Thank you very much for your post! My first comment is that I thought I had changed the forum settings to allow posts by registered users (registration accepted by me) without my previous approval. In fact I come here from time to time to delete "new registered users" waiting from my approval which are, in fact, spam users. After deleting 10 of them I saw a post waiting for my approval. So sorry for this. And if someone read this (and if I am not able to correct the forum settings) and have a post waiting for my approval just write me a note!

Regarding the subject, I have been thinking about that. I looked at the simulation file from SeaWi and noticed that it is extremely large. The ESP8266 has 4MB (mega bytes) flash memory but in the module that the multiplexer uses, 3MB are used for a File System. I could reset that division to get more than 1MB for programme space but I have little or no experience on that. Also on the 1MB for programming only a part is reserved for variables (and I am already using about 70% of it). I even though about the user interface. I could just add an extra button "Simulation ON/OFF" side by side with the one called "Set Factory Settings". If the user presses that simulation button, the readings of P1 and P2 would be ignored and values would be read from memory. All the rest would be unchanged. To stop that operation a disconnection from the power supply would suffice or pressing again "Simulation ON/OFF" . When simulation was ON, the color of the web page would be different. So the only problem would be to place that big file in memory (coded as constants) and specify the time interval between every Nmea sentence.

If the SeaWi file was smaller I had it done already and would made it available as optional firmware version. On the developing phase of the multiplexer and since I have my boat in Greece and live in Portugal, I used the NmeaStudio version that you refer to. I copied a set of sentences from the log generated from NmeaStudio (including AIS) and I programmed 2 small Arduinos sending these sentences out. One sending non-AIS sentences at 9600 and the other sending AIS sentences at 38400. Since there are 2 Arduinos they are independent from each other and that is the way I test the multiplexers units that I built. I look in the SeaWI if there are errors. For the simulation I would need to choose the sentences more carefully, with "my boat" stopped at some marina and for AIS with 2 or 3 vessels near by and, may be, "on anchor". The file to be placed in the memory would present no problem.

So your post is extremely valuable for me and users! I will return to it if I go ahead to include a simulation mode (at the moment I am a bit busy writing a manual for a kit version of the multiplexer that I pretend to make available at a reduced price).

I am extremely happy that you find the multiplexer a good purchase!

Best Regards, Luis

JohnH
Posts: 3
Joined: Tue Jan 02, 2018 6:19 pm

Re: Bidirectional Multiplexer

Post by JohnH » Fri Jan 19, 2018 5:47 pm

Luis, thank you for the thoughtful reply. I don't mind the moderation of a new posting, because it allows you to keep the thread succinct and a useful resource for potential users - and any more detail could be discussed directly.

Otherwise, just a few comments:
- You could truncate the simulation file, as it doesn't need to last for more than a few minutes, and perhaps repeat it.
- SailSofts's GPSSimul and NemaStudio applications can also transmit over UDP, so I found them useful for trying display PC and tablet apps such as SeaWi without the multiplexer in circuit.

I shall look forward to using the multiplexer on a real sailing trip, perhaps early March - and will try to record some meaningful GPS/AIS/Depth data! John

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