Paul Hubbard pfhubbard@ucsd.edu
June 21 2010

UPDATE March 15 2011 - updated for the JSON interface in buildbot 0.8.3. Working well.

Picture: 
 http://github.com/phubbard/arduino-buildbot/raw/master/a-b.jpg

This project is an evolution of the 'office-weather' project:

http://github.com/phubbard/office-weather

This version is a complete re-write
* Switch from USB communications to TCP over ethernet, by using the 
  Arduino ethernet shield: http://www.sparkfun.com/commerce/product_info.php?products_id=9026
* Add a 3-color LED as status indicator: http://www.sparkfun.com/commerce/product_info.php?products_id=8579
* Python code is much more complex - more below

Goals:
* Use Arduino to monitor our Buildbot and the latest build. If it breaks, red light, if all tests are passing, green light, maybe other colors if useful.
* Include the previous weather station functionality
* Be a fun hack

Hardware requirements:
* Arduino
* Ethernet shield
* BlinkM RGB LED (URL above)
* LM35CAZ Nice, TO-92 cased, temperature sensor with 0-5VDC output and no
   external components required. A few bucks from National.
   http://www.national.com/mpf/LM/LM35.html#Overview
 * Ohmic Instruments SC-600 humidity sensor and signal conditioning module.
   http://www.ohmicinstruments.com/pdf/SC-600.pdf
   About $15, quite cheap for a sensor this nice. You need an external RC
   lowpass, so two more components in the circuit. See the PDF.
* Optional mini breadboard

Software requirements:
* Python
* Twisted
* Arduino plus BlinkM libaries

Current status and functionality:
* The python code polls the buildbot, extracts build status and merges the most 
  recent builds. From this, it chooses an LED color.
* In parallel, the python code connects to the Arduino, sends the current color 
  as a 3-byte RGB string, and then reads two ADC counts that correspond to temp
  and humidity readings. Units and calibration are done in the python code, as
  before.
* Nifty animated BlinkM startup sequence when you hit reset. ;)
* TAC file from deldotdr for running as a daemon

To-do:
* Tweak and tune