Implementing Comparators with Hysteresis

You need to implement a comparator circuit with hysteresis, and you pull up some app notes. They look something like this, credit to Analog Devices:

If you have a circuit in hand, there are a dozen or so discussions online to determine the comparator’s characteristics: high threshold \$V_{TH}...

Smoothing Rates of Change

This is probably something that would have been obvious to everyone else, but stumped me for a bit when I came across it the other day. I was looking at the rate of change of a sequence, and my smoothing algorithm wasn’t doing any better than just subtracting two points in the sequence farther ap...

Writing a Raspberry Pi Image Using the Ubuntu DiskUtil

The basic steps for loading a Raspberry Pi image after downloading and unzipping the image (to /dev/sdg1 for example) are:

sudo umount /dev/sdg1
sudo dd bs=4M if=2013-09-10-wheezy-raspbian.img of=/dev/sdg1
sudo sync

This didn’t work for me. It seemed to write the data but left the card unbo...