Nanobaro - NMEA/USB barometric sensor, easy DIY electronics project

Andrew_Trayfoot

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Should work without modifications. The Nano outputs the USB-Serial also as TTL level serial output at 4800 bps, see Serial - Arduino Reference

The Raymarine e7 has a 4800 bps NMEA0183 input. You might need a level shifter, although it's safe to try and see if it works by just connecting them. Good luck and let us know if it worked!

So i now have this built and working and can see the MMEA data on my PC on the Arduino serial monitor over USB (once I found a USB cable that actually worked!).

I have tried it directly to my display head (Onwa KMr-6 KMR-6 - ONWA Marine Electronics Co. Ltd.) and it cannot see the 5v serial output from the Nano . Can someone point me at a suitable 'level shifter' to get it up to 12v.

I have found lots on google, but have no idea what is suitable..

Thanks.

Andrew
 

Yngmar

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Hook up the serial output (TX) and GND from the Nano to one of the 4800 bps serial inputs on the Onwa. Try swapping the pins if it doesn't work (RS232 and RS442 use negative voltage for 1). Don't know if you need to enable the port on the Onwa or anything like that. If it doesn't work, you'll have to troubleshoot - see what's coming out of the Nano and what the Onwa expects.
 

Yngmar

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don't you really need level shifting boards for that?

Ideally, yes. But because NMEA0183 is electrically poorly standardized, most marine electronics equipment is fairly liberal in what it accepts as input for a NMEA0183 port and you often get away with just hooking it up like that.

Don't try it the other way though (input on the Arduino side will definitely need a driver circuit). But the Nanabaro is output only.
 

Andrew_Trayfoot

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Hook up the serial output (TX) and GND from the Nano to one of the 4800 bps serial inputs on the Onwa. Try swapping the pins if it doesn't work (RS232 and RS442 use negative voltage for 1). Don't know if you need to enable the port on the Onwa or anything like that. If it doesn't work, you'll have to troubleshoot - see what's coming out of the Nano and what the Onwa expects.
Have tried hooking up the pins but got nothing.
Bit uncomfortable about reversing the pins as I have lots of other NMEA stuff on the same ground that works fine

Have bought some of these to try:

ICQUANZX 10pcs 4 Channels IIC I2C... ICQUANZX 10pcs 4 Channels IIC I2C Logic Level Converter Bi-Directional Module 3.3V to 5V Shifter: Amazon.co.uk: Electronics & Photo

But may go with the recommendation from Vas
 

Yngmar

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Bit uncomfortable about reversing the pins as I have lots of other NMEA stuff on the same ground that works fine

The Onwa page says:

4 input ports are opto-isolated

So should be safe to try. May or may not work if the voltage is too low for the optocouplers, but I reckon it might. But yeah, the proper way is to build yourself a driver circuit.
 

Andrew_Trayfoot

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Thanks

WIll source components this week and put it all together. Was about to cut a big hole for the Nasa Meteoman, but then realised it does not have an NMEA output. Nano box can be out of sight and interfaced into already existing plotter with no hassle. Will let you know if it works.

And thanks for the link. Never know Arduino outputs serial on 0 and 1, which is what I was wondering about...
Did you ever get this working over serial rather than USB?
Can't get mine to output anything. It works fine on usb
 

Skipjohnsen

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Hello,

After some discussions on No Temperature in Dashboard - Cruisers & Sailing Forums i am pleased to present the first version of my Arduino code.

I was experimenting with a bme280 and an Arduino Nano for usage with OpenCPN and adjusted the NanoBaro mentioned above to print NMEA0183 sentences with Values for Pressure. Temperature and Humidity.


The code isn't ready and nice but somehow working.
If interested please have a look:

https://github.com/roaxth/NanoBaro-b...dy-for-OpenCPN


Feedback and improvements are highly appreciated.


Best Regards
 

dolabriform

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Hello,

After some discussions on No Temperature in Dashboard - Cruisers & Sailing Forums i am pleased to present the first version of my Arduino code.

I was experimenting with a bme280 and an Arduino Nano for usage with OpenCPN and adjusted the NanoBaro mentioned above to print NMEA0183 sentences with Values for Pressure. Temperature and Humidity.


The code isn't ready and nice but somehow working.
If interested please have a look:

https://github.com/roaxth/NanoBaro-b...dy-for-OpenCPN


Feedback and improvements are highly appreciated.


Best Regards

Hi there, I've just replied to your message on github, thanks for taking the time to post your fix.
 

AngusMcDoon

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I was experimenting with a bme280 and an Arduino Nano for usage with OpenCPN and adjusted the NanoBaro mentioned above to print NMEA0183 sentences with Values for Pressure. Temperature and Humidity.

I've made a NMEA2000 pressure sensor. I can see the pressure reading from it on my Raymarine i70s and Axiom+ displays. I haven't done temperature or humidity as temperature is just that inside the box and humidity is always on the soggy side of damp.

The device also sends out the pressure reading in NMEA0183 format over Bluetooth so OpenCPN can grab the data and display it. The device does other stuff too - it's a NMEA2000-NMEA0183 via Bluetooth bridge so all my data on my NMEA2000 network can be sent/received to/from OpenCPN on a tablet (or laptop) via Bluetooth. It also reads AIS data in from a transceiver in NMEA0183 format and squirts that out over Bluetooth to OpenCPN.

I'm also developing an Android anchor watcher app. This will receive all the same data from the above device via Bluetooth. Anchor watching will look at any or all of depth, heading, windspeed, pressure change, SOG as well as the usual location. All of these data can have limits set which will set off an alarm if any are exceeded. Running on a phone I can sleep with the app running by my head as I dream of drizzle and midgies.

I'll open source it all when it's complete. I have all the technical hurdles covered now - just need to pad out the missing functionality. The Bluetooth bit was tricksome, and Android development and Java are all new to me. The device runs on a ESP32 based board developed using ESP IDF.
 

Andrew_Trayfoot

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Hello,

After some discussions on No Temperature in Dashboard - Cruisers & Sailing Forums i am pleased to present the first version of my Arduino code.

I was experimenting with a bme280 and an Arduino Nano for usage with OpenCPN and adjusted the NanoBaro mentioned above to print NMEA0183 sentences with Values for Pressure. Temperature and Humidity.


The code isn't ready and nice but somehow working.
If interested please have a look:

https://github.com/roaxth/NanoBaro-b...dy-for-OpenCPN


Feedback and improvements are highly appreciated.


Best Regards
Does it send the data over rs232 or USB or both?
 
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