Thanks, for the suggestions. Just for clarification, I'm using 1WE, 1CE, 1RE (or 1WE - 1 CE/RE) for each rodeostat. For now I'm running each rodeostat in individual beakers.

Anecdotally, I ran the same experiment using a research-grade multi-channel potentiostat (from GAMRY) and didn't see cross-talk in a single beaker. Specifically, I ran high currents using a single Ag/AgCl wire (reference+aux) for each channel. The stability of each cell degraded randomly. Previously, when using a few rodeostats, all WE signals decayed at the same time (suggesting the 3 wires were acting as a shared reference/aux).

Ordered a USB isolator, will wait before splicing my teensy boards. They're cheap enough to replace, but I'd rather not need to if I can help it.

For setup reasons, I've been using a USB hub to power and operate a few rodeostat teensy PCBs simultaneously on my laptop.

1. I tried to run multiple sensors within a single experiment cell (shared buffer solution), but have observed what I think is cross-talk between the devices (particularly when running 2 electrodes for electrodeposition). Are there any issues I'll need to consider here?

2. I sometimes experience more noise in my experiments. I was thinking about just swapping in larger caps on the TIA but it doesn't seem to happen all the time. Another thought was that the power being supplied by my USB hub might be contributing. Any reason to worry? What's the best way to power the rodeostat externally while using USB for serial comm? I see the P15, P16 (5/3.3V jumpers) next to the expansion headers as one option. However, I assume I would need to somehow physically disable the USB-provided +5V power away from the board?

Thanks in advance! brad

Updated to 0.0.4 and it works. Thanks again!

Hi Will,

Thanks for the tip. For now I'm going to manually disconnect CTR from my sensor.

I did run into a minor problem where the commands aren't recognized by the device. I'll try to refresh the device with newer firmware.

OSError: command, getRefVolt, not found, {'success': False, 'message': 'command, getRefVolt, not found', 'response': {}}

Brad

Looking at the example file get_ref_volt.py, I believe it is relatively easy to create a test to measure the potential between two electrodes. Unfortunately, the firmware itself doesn't support open circuit ("floating") potentials; the working-reference (output) potential is set to 0V at initialization.

Will there be issues if I remove the setVolt(..) commands defined in these methods?

• SystemState::initialize()
• AnalogSubsystem::initialize()

To evaluate the changes, I plan to run a simple python script like this:
port = '/dev/ttyACM0'
sample_period = 5
dev = Potentiostat(port)
t_start = time.time()
while True:
ref_volt = dev.get_ref_volt()
t_current = time.time()
print('%05.0f,%04.2f' % (t_current - t_start, ref_volt))
time.sleep(sample_period)

Any thoughts?