Info on Rodeostat



  • Hi,

    I'm interested in using rodeostat for my project, which is trying to use screen printed electrode and combine it with 2 LED that will light up one at a time according to the reading from rodeostat.

    I'm new to this potentiostat and if anyone willing to share their knowledge on rodeostat is much appreciated :smile:

    Thanks :grin:



  • Hi @eonesyafie, I designed the Rodeostat and wrote the firmware and software for it. I'm happy to try and field any questions you have. We've used it with both the Pine and Zensor screen printed electrodes with good results.

    Currently, controlling the potentiostat requires a little bit of programming (in Python) as there isn't any PC software with a graphical user interface (GU) I'm working on the GUI software at the moment. We have Python library which can be used to write programs to set test parameters, acquire data, etc

    The repository for the library (and hardware designs) is here https://bitbucket.org/iorodeo/potentiostat/src The library is in "software/python" and more examples can be found in "software/python/potentiostat/examples".

    There are a couple of ways you might synchronize your LEDs and the Rodeostat.

    • First, if your timing requirements aren't too precise - if within a few ms is good enough - then you might use the Rodeostat in manual/direct mode. In this mode the output voltage is set via the (Python) program on the PC (which you write) using the "set_volt" method. Similarly, the current is set with the "get_curr" method. Then you could perhaps have a second device - such as a Arduino, Teensy, etc. - controlling the LEDs from the same program. That way you could turn the LEDs on/off when you need to based on the reading. There are some example programs demonstrating manual/direct mode here http://stuff.iorodeo.com/docs/potentiostat/examples.html#manual-direct-control

    • The second option is to use the DIO expansion header on the Rodeostat to control the LEDs. This would give you really good timing, but it would also be more work as it would require some modifications to the firmware.



  • @Will-Dickson thank you for the links.
    May i know, rodeostat has option where teensy is already mounted in it right? Is it possible to use that to control the LED?



  • @eonesyafie

    The Rodeostat comes with the teensy 3.2 pre-programmed and already mounted here
    https://iorodeo.com/collections/cheapstat-open-source-potentiostat/products/potentiostat-shield

    Yes you could definitely use the Rodeostat's teensy 3.2 to control the LEDs. On the Rodeostat PCB there are two 5x2 expansion headers which expose various DIO pins on the teensy which you can use. The ability to toggle the expansion header IO pins via USB commands from the host PC is not included in the standard firmware . So you would need modify the firmware to toggle these pins - to control the LEDs - yourself.

    The firmware for the Rodeostat is just an Arduino sketch. so if you are comfortable programming Arduinos modifying it should be pretty straight forward. You could probably quickly hack in this feature by adding a few lines to the SystemState's "updateTestOnTimer" method - just check the time and set desired digital outputs for the LEDs using digitalWrite based on time or the current measurement, etc. The "updateTestOnTimer" method can be found in firmware/libraries/potentiostat/ps_system_state.cpp starting on line 353. With the default settings it is called at 5kHz - so every 200us.


Log in to reply