Convincing the Davis Instruments Vantage Vue® Wireless Station
to Join the Internet of Things


Background:

Acronyms used in this article:

Drawing of Station

DIVVW = Davis Instruments Vantage Vue® Wireless Station

SFAQT = Super Fun Adventure Quest Time (This group's blog.)

Cost of the project:

$35--Wireless adapter for remote logging Davis Instruments Vantage Vue® Pro.

Plus the variable costs of the weather station and a computer upon which to receive data.

Our tale:

“How much rain did you get?,” drawled the leathery-skinned old farmer.

Viktor gritted his teeth and said, “1.43 inches.”

“Ha! I got 2.5 inches! Haw haw haw!”

“How in tarnation can you possibly have gotten an inch more of rain, when your rain gauge is less than fifty feet away from mine?”

Such was the ongoing feud into which SFAQT personnel found themselves embroiled.The farmer that grazed his cows on the Lab's land always managed to report an inch more than anyone else after a rainstorm. This was a problem, since the Lab was engaged in an in-depth study of local and regional weather patterns. The Lab tracked hurricanes, rainfall, average wind speeds, lightning frequencies, and all the other nifty weather-related occurrences that can be tracked, followed, quantified, recorded, or measured.

The farmer's reported extra inch of rain was destroying our data set.

“That weather-hating curmudgeon is destroying my scientific survey! I will bury that mocking rustic! I will show him! I will show them all! I will buy the most sophisticated weather station I can find, and prove to him and all the mocking mockers and lying liars that his data-collecting is flawed!,” proclaimed Viktor, sounding more than a little like the raving mad scientist Bela Lugosi played in "Bride of the Monster."

But the years years went by, and Viktor seemed no closer to having his revenge.

Finally, one day, a kind associate, who knew of the rain gauge contretemps, called with important news. He had found a fantastically sophisticated, reasonably-priced weather station: the Davis Instruments Vantage Vue® Wireless Station (DIVVW Station).

It was and is perfect. A truly great investment. The DIVVW Station is an incredible weather-collecting machine that collects weather-related data in both wide varieties and impressive amounts.

No doubt, Gentle Reader, you know that SFAQT Laboratories lives and breathes data. It is the cream to our coffee, the butter to our bread, the AC to our DC. It is vital to our mission, viz, to know the secrets of the Universe, and to smite without mercy the enemies of Science. And how, we ask you, can we smite down the ill-conceived arguments of our enemies without without first collecting quivers full, nay, formidable arsenals full, of data?

And so, to return to our narrative, it was with great anticipation that we set up our weather station. The sensors were placed on a hill on the Lab's campus, and the receiver was placed in the window of one of the Lab's buildings.

The installation proved to be so easy, I was sure that the station couldn't possibly work when powered up. But I was wrong--the data poured in like a mighty river after the spring thaw.

After a quick celebration to welcome the new data-collecting unit to our scientific family, Viktor decided that the unit was worthy of being connected to what he so charmingly still calls "The Internets." Not all data collecting units get that honor, but the DIVVW Station had already proved itself special.

Now Davis, the company that sells this unit, already has modules for connecting to the Internet.

And it has helpfully included software, as well.

Viktor wanted to see if we could get the data in the SFAQT way, according to that saying we have around here, “There's the right way, the wrong way, and the SFAQT way.”

But could we connect the weather station without using the commercially available product?

After making a few online searches, Viktor stumbled across this inspiring article:

Mad Scientist Labs - Davis Weatherlink Software Not Required

We learned that we could hack this machine. Our excitement built up. The mere thought that every employee at the Lab would soon have weather data streaming into his or her consoles made my heart flutter.

Conclusion:

Now the data can be used to to make charts, graphs, and it becomes accessible to the people with whom you want to share it.

This data is extremely useful in convincing the enemies of Science that they are absolutely wrong.



PROJECT NOTES:

Note on project notes, Here Viktor describes the project in his own words:

I noticed that most of the hacks for the weather station seem to be of two types. You could either make your own serial interface, or use wireless modules, like the Digi Xbee modules.

The first hack to make your own serial interface is straightforward enough and is outlined in the . above-mentioned article

The second hack, using the wireless Digi Xbee modules, was quite intriguing.

First, you need two modules: one on the remote end, and one on the receiving end.

Second, you need an adapter for the second module to convert the data back into a usable form for a desktop computer.

Using the Digi Xbee module and USB-to-Digi adapter means that the remote station shows up via radio as a serial port. So, it easily integrates with the Davis software and other online software. This is great if you're into that sort of thing. Which we here at the Lab aren't.

This particular hack is handy in that it removes the need for the second radio module, provided that you already have an existing 802.11 network.

Digi recently started making a 802.11 module in the same form factor as the previous Xbee modules. It's called the XBee Wifi module

UPDATE: that model has been superseded by a new one that we have not yet been able to obtain.

This module does take a bit of configuring to get it to work. We recommend using a static IP address. Just pick one outside the range that your Wifi interfaces give out on dhcp.

How to configure the interface:

For help configuring the interface see this article or this one.

The first time you configure it, you'll need a way to talk to it via serial. You can use one of Digi's demo boards or use an Arduino Wireless Shield

The Arduino should be running a blank sketch.Make sure the the switch is set to USB mode on the shield. See this Page for clarification.

My config:

Notes on Source and Destination Port:

The radio module listens internally on port 9001 and transmits to a server also on port 9001.

The Digi software is confusing here. The number it wants should be in HEX, so 9001 = 2329 in HEX.

To connect the Digi to the weather station we used jumper wires and headers, instead of a breakout board.

Photo of Hookups

The only wires necessary are for TX,RX, 3.3V, and GND. The whole hack will tuck nicely inside the unit with no external wiring.

At this point it is possible to telnet to the device using the address and port that was assigned to it.

telnet 192.168.1.156 9001

Now, you can issue such commands as HELP, TEST, and most importantly STRMON and its counterpart STRMOFF.

Once STRMON is activated you should start seeing codes sent every 2.5 seconds.

Madscientistlabs and others decoded the format of STRMON data: format of the STRMON data

Finally, the real magic happens by using the Wifi module to send data to a server.

I wrote a quick python script to listen on port 9001 and told the Wifi module to send data to that machine on port 9001.



Schematic:

Schematic



Source:

collect_strmon.py


CODE NOTES:

The code listens to a port. When a connection is detected it waits 500ms for the packet to fully arrive, then decodes it.

Once it has seen an update for temperature, humidity, wind speed, and wind direction, it forwards that data to a remote server to be logged.



Licenses:

Software Copyright (c) 2013 Viktor Criterion

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

MIT-License

Hardware Copyright (C) 2013 Viktor Criterion
Licensed under CERN v1.1

Artwork Copyright (C) 2013 Viktor Criterion Licensed under Creative Commons.
Attribution 3.0 Unported (CC BY 3.0)

Vantage Vue® is a registerd trademark of Davis Instruments Corporation CORPORATION CALIFORNIA 3465 Diablo Avenue Hayward CALIFORNIA 94545. No ownership of the the name is implied here.

XBee® , XBee Pro® , and XBee Wifi are registered trademarks of Digi International Inc.