learning the ropes

I continued my experiments towards one of my final project ideas: sonifying transactions. First, I exported all of my financial data (1999-January 2007) from Quicken into a tab-separated file and brought the file into OpenOffice Calc to tidy it up. After I extracted a selection of gasoline purchase from May 2001-May 2002, I realized there was something missing from the data. I’m interested in the rhythm of the purchases against the backdrop of the days and weeks. Since I didn’t purchase gasoline daily (thankfully), I needed to write a program that would insert the rest of the days into the transaction data. Doing this by hand seemed like a big pain — especially once I start working with the full dataset. To avoid having to make the algorithm aware of the number of days in each month, I simply generated a list of dates in OpenOffice Calc and compared it with the dates in my transaction list.

[ download code ]

After filling out my data, I started working in Processing and cSound to sonify the data. Starting simply, I used oscillators of different frequencies to represent days, weeks, and the transactions. The following Processing sketch is based on a sketch I wrote for my Google vs. Microsoft experiments. The classes were overkill for this application, but they were helpful for keeping the Google vs. Microsoft program legible.

[ download code ]

[ listen ]

If you’re working with an Arduino NG and an SPI controlled device you’re working with is not functioning properly (an AD5206, an accelerometer, etc), you’ll need to perform surgery on your ‘NG to remove the SMD LED from digital pin 13. Idiscovered this while helping YouJeong troubleshoot her AD5206. We looked at everything from the wiring to the AD5206 chips to source code to finally the Arduino itself. The only reason I was able to figure this out is that I saw that YouJeong’s Arduino NG had an LED on pin 13 (which is one of the pins Arduino uses for its SPI interface). I noticed when trying the most basic “blink the LED” program that an LED inserted between digital pin 13 and ground was very dim. When I jumped it in parallel with the SMD LED on the Arduino circuit board it was brighter. Using a multimeter we found that the pin 13 was only giving us 1.92V when pin 13 was set HIGH.

I suggested we search for “Arduino NG SPI” and we found a thread in the Arduino forums about this issue. To rectify the problem, I removed the pin 13 LED from both of her Arduino NG boards and SPI started working properly.