# Presentation at BCCE

I’m giving a research talk at the Biennial Conference on Chemical Education, which is being hosted by Purdue University. The presentation is on developing a curriculum for analytical chemistry based upon building scientific instruments using the M4 Express microcontroller. I mentioned a few links in the talk and here they are for those who snapped a picture of the QR code:

Some pics and other relevant info will follow the talk.

# FeAtHEr-Cm Whitepaper

A few people have expressed interest in this project, so I figured I would put together a whitepaper highlighting what problems I’m trying to solve with FeAtHEr-Cm, how I plan to go about doing it, and how others can participate. If you fall in to this category, take a look.

# FeAtHEr-Cm gamma tests

I received the PCBs for the gamma (3rd) version of the FeAtHEr-Cm potentiostat. I really like how this one comes together. Complete with 2 20kohm pots for adjusting virtual ground and iR compensation plus the passives all fit in a single 14-pin socket which allows students to explore how changing these components can influence the performance of the instrument (and to hack it to do things it’s not intended to do). Plus, it’s got buttons! This is the version that students will see this fall.

# Signal processing with Mathematica

I’ve been working on some instrument design projects and have hit a brick wall of sorts. My prototypes are riddled with noise, most likely 60 hz. My thought here was to learn a bit more about signal processing to (a) see if I can get a better understanding of what’s going on and (b) see if this is a possible project for students.

So the setup is as follows. I’ve got an Arduino microcontroller that does one of two things, it either reads the signal from a noisy light detector (in this case, an LED connected to an op amp in a current-to-voltage configuration) or – for debugging purposes – outputs a fixed signal frequency by printing $A0 + A cos(2 Pi f millis()/1000)$ where $A0$ and $A$ are amplitude offset and signal amplitude, respectively, $f$ is the frequency and since millis() returns a value in milliseconds, it is divided by 1000. To enact a sampling rate, I set a delay(dt) in the loop routine where dt is the delay time in milliseconds.

On the *Mathematica* side, it’s pretty easy to read the serial data from the Arduino with d = DeviceOpen["Serial", {<port>, "BaudRate"-><baudrate>}] with replacing <port> and <baudrate> with your values. The code below is a tad clunky, but works well at grabbing data and converting it into a format that Mathematica wants.