Send pulse from one Photon to another 30 feet away


I need to send a pulse from one Photon to another. The second Photon is about 30 feet away.

Will this work or will the voltage drop prevent this from working? What is the best way of doing this?

Thanks in advance.


If you have a use case that requires this to be a physical link you would normally use a dedicated transceiver of somesort like RS485, that would then be capable of full data transfer rather than just a pulse. I would think that trying to do that driven directly from the Photon pins would be a bad idea, a cable that long can easily pickup all sorts of interference which could even damage your device. However you could probably knock something up using an opto-isolator at each end that worked…


Yes @ScruffR, certainly, WiFi is always an option but I was hoping for a wired approach to avoid potential radio interference and simplify the installation. Also, I am trying to minimize transmission delays.

Thank you @Viscacha. I agree with you that a RS485 is a better approach.

Would I in this case use 2 units of something like this? How would these be wired? Do I swap the A+&B- between the two Photons?

I have not used opto-isolators before and would appreciate a link of how it can be used.


The answer to your wiring question is right on the Amazon page for that board :slight_smile: