##What is this page about: The WheeStat is a potentiostat, which is an instrument used to study electron transfer reactions between species in solution and electrodes. There is a PublicLab wiki page that discusses potentiostats [here](http://publiclab.org/wiki/potentiostat). ##Other pages on the WheeStat: The history of the project was first described [here](http://publiclab.org/notes/JSummers/11-02-2013/potentiostat-notes-1-wheestat-history). Discussions of how to build the WheeStat hardware are described [here ](http://publiclab.org/notes/JSummers/12-30-2013/potentiostat-notes-3-wheestat-5-1-fabrication)and [here](http://publiclab.org/notes/JSummers/01-08-2014/potentiostat-notes-4-fabrication-made-easy). While the former note discusses how to build your own pcb, the latter tells how to order the pcb from OSH Park. Some early discussion on the software and graphic user interface are [here](http://publiclab.org/notes/JSummers/12-20-2013/potentiostat-software) and [here](http://publiclab.org/notes/JSummers/01-04-2014/potentiostat-notes-3a-timing-de-bugged). A discussion of making low cost electrodes is [here](http://publiclab.org/notes/JSummers/01-09-2014/potentiostat-notes-5-how-to-make-low-cost-electrodes). Use of the WheeStat and low cost electrodes in monitoring airborne hydrogen sulfide is [here](http://publiclab.org/notes/JSummers/03-10-2014/quantifying-airborne-hydrogen-sulfide). ##Setup: To run the WheeStat, you need to install the appropriate drivers on your computer and have the application file for the GUI installed. **Drivers:** The WheeStat is based on the Stellaris or Tiva microcontroller development board from Texas Instruments. The first thing you will need to do is download and install drivers from Texas Instruments. Drivers for the In-Circuit-Debug-Interface (ICDI) can be downloaded from this web page found [here](http://www.ti.com/tool/stellaris_icdi_drivers). At the same web page is a link to instructions for installing the drivers on windows machines. I recommend you print out the instructions and have them handy when installing the drivers. **GUI Application Files** You should be able to get this software from our GitHub page ([here](https://github.com/WheeSci). You will need the application file (.exe) and the folders containing the source code, the libraries, and the data files. These will all need to be in one folder on your computer. ##Source Code## While the files described above can be used to run the WheeStat, some users may wish to change the functionality of the microcontroller or GUI. In addition, if you are building the potentiostat yourself, you will need to install firmware on your microcontroller board. **Microcontroller Code:** The firmware was written using the program Energia, which can be downloaded from www.energia.nu. You will need the most recent version of the WheeStat source code and the altSPI library. As of this writing, the most recent version is WheeStat5_4a. You should be able to get this software from our GitHub page ([here](https://github.com/WheeSci) Let me know if you have trouble with this. I am a little slow on updating software.). Once you download the program, you will need to have the altSPI library (altSPI.h and altSPI.cpp files) in a folder called "libraries" inside your sketchbook folder. **GUI Code:** The Graphic user interface (GUI) was written using a program called Processing that can be downloaded from processing.org. Source code for the GUI can be downloaded from the same GitHub page described above ([here](https://github.com/WheeSci)). As of this writing, the most current version was WheeStat5_4. ##Graphic User Interface: The following video shows the setup of the GUI and some of it's functionality. It shows the expected behavior of the instrument, tested using a resistor of known value. The demonstration shows that Ohm's Law can be used to predict the current / voltage behavior of the voltage ramp experiment. The following video demonstrates some of the experiments that the WheeStat is programmed to do: