May 12
Hard to get machine-readable weather data
Today, I interfaced an Arduino to a stepper motor – the hardest bit in the end was figuring out which pins of the Unipolar stepper motor do what. The motor, available as Jameco 171601, has six wires – yellow, red, orange, black, green, brown – which come out in a connector. The most useful reference I found was Tom Igoe’s Stepper Motor Control page. In the color sequence above, the wires are those numbered 1, 5, 2, 3, 6, 4 in Igoe’s diagram.
As a demonstration I wanted to turn it into a little weather toy, but it has been very difficult finding machine-readable real-time weather data on the web. The NOAA site is chaos. Eventually, I settled on this:
It was easy to grep and sed the data I wanted out of its text and tables. God forbid that whoever produces this should take a more literary turn – then I would need NLP! 