After Professor Fzz’s wireless base station died, he found himself continually looking at where it use to be to monitor the activity lights during downloads. He wanted to replace it with something else to help him visualize this data — the Internet Pressure Gauge was born.

The electronics are probably overkill for this application, but they work well. A Devantech USB-to-I2C convertor takes commands from the Mac over USB, and sends them via an I2C bus to an SD21 21-channel servo controller board. I’m only using one channel at the moment, so expect more computer controlled hardware in the not too distant future.

The software is pretty trivial, comprising a 40 line program in C to send commands to the servo controller, and a 30-line script to get the network statistics and call the C program.

Too bad you could do pressure gauges for blog comments, with a pressure valve whistle that releases when things get over-heated.

Internet Pressure Gauge