Receiving and decoding weather stations in Colorado

[jeromeinco]

I've had some fun recently receiving signals from nearby weather stations in Colorado : http://scalaeveryday.com/?p=4

[cooper]

I bow to your inventiveness and perseverence.

I had a little trouble going from the binary data and the description you provided to the actual numbers you report.

As you said, you have to reverse the bits. After that the leftmost of the 6 data bits from the second byte is the most significant bit and the rightmost of the 6 data bits from the first byte the least (the text suggests to me you need to chop off the 01/11 for only the first of the two bytes but your github code set me straight).

Also, the site id produced isn't so much the site id but rather the sensor id and setting the last numerical value to 0 gives you the site id, so those 3 readings you present on your page are all for 140 - the Blue Mountain site.

The shown JSON data doesn't match the binary data presented. The numbers for the provided binary are, respectively:

000010 001110 (142) 000010 101100 (172)

000010 001101 (141) 000000 011110 (30)

000010 001111 (143) 000101 011000 (344)

I believe that the 6 most significant bytes of the value indicate what's represented here. So that 000010 means it's the air temperature in fahrenheit and 101100 is the real value which would be 44.

000000 (for 141) means it's the humidity in percent which has a value of 011110 or 30. Finally 000101 means it's the fuel moisture (dafuq??) and 011000 means a value of 24.

According to the website the presented values are within the expected range for the timestamp given (and your clock is off by at least 6 minutes).

Do these observations match the data you've collected from the other sites?

Truly an awesome find, this. Thanks for that. :)

Edited April 9, 2014 by Cooper