connect anemometer to pico

I am a total newbie to microcontrolers but I have lots of experience as a js web dev - thats how I came here :)

I would love to build a web applicaiton that would show weather data, specificly wind speed. Do you think it would be easy/possible to connect http://www.maplin.co.uk/p/maplin-replacement-anemometer-for-n25fr-n76nf to pico? Its very cheap and would be great if it worked out.

As soon as I get it to work and im in js im sure that I can figure out a way to compute any input from the sensor to meaningful information and send it to some web server. Or even send raw data and process it on the web server.

Any help would be greatly appreciated.

Wow, good find! That's amazingly cheap!

I had a quick google and I couldn't find much information about the sensor. I'm pretty sure it'd be easy enough to connect, but it's finding out how.

I think realistically, unless you can find someone else who has connected it to a Pi, Arduino, or something, you'd have to take it to bits, take some photos, and post them up.

I guess for £2.50 you could probably afford to buy two and break one apart if it's not obvious how to get into it.

Most likely it'll be a hall effect device - there'll be 3 wires you need to connect, one will be GND, one power, and one will be an output that pulses once for each revolution. It's then pretty easy to count that with the Pico...

Hi,
looks like there are only the scales and the RJ11-connector,
but the following info may be helpful from the http://www.maplin.co.uk/p/maplin-replacement-anemometer-for-n25fr-n76nf

· 10 months ago
Internally, it is just a reed switch that is closed by a magnet on the rotating head. This means that there is one brief switch closure for every complete revolution of the head. The 2-wires to the RJ-11 connector (positions 3&4) come from the two terminals of the reed switch.

Oh perfect - I didn't look there! So yeah, wiring it up will be trivial.

You could wire to anything but let's say you chose to wire one side to GND and one to B3:

var lastRotation = getTime();
function anemRotated(e) {
  var d = e.time-lastRotation;
  lastRotation = e.time;
  console.log("Speed = "+(60/d)+" rpm");
}
pinMode(B3, "input_pullup"); // activate pullup resistor
setWatch(anemRotated, B3, {repeat:true, edge:"falling"});

You'd need to run something every few seconds that's check whether it had in fact stopped turning, but otherwise that's it...