Ethernet connectivity (RJ45) on a Cyton Board
Good afternoon everyone.
I hope you're doing well wherever you are.
I'm involved in a art performance merging science and art (here), where we are gathering a bunch of biological data from the artist. In some configuration we're expecting to have some issue with the wireless/Bluetooth communication from Cyton because of electrostatic noise (or spectator with their Bluetooth activated).
Thus I need to be sure that there is a reliable backup solution where I can collect the cyton data with confidence if the wireless connection malfunctions. Is it then possible to adapt and arduino ethernet shield (or affiliate) to connect an RJ45 ethernet cable directly to the card?
All the best
Comments
Hi Remi,
I noticed that your video showed the Emotiv EPOC, which only has Bluetooth connectivity. If that works ok in your performance, I would expect the Cyton to behave similarly. One strategy for your audience would be to suggest they either turn their devices off, or place in airplane mode. Actually cell phone radio frequency bands are NOT in the same region as Bluetooth and wireless. So they could just turn off Bluetooth and Wifi.
There is a Wifi Shield available for Cyton. Another possibility, but it has no RJ45 ability.
If you run a usb extension cable from your laptop, this can place the Cyton dongle (RFduino), very close to the RFduino on the back of the Cyton mainboard. Thus making the signal strength very strong between dongle and Cyton, and less able to be influenced by other Bluetooth. Such usb extensions are available in various lengths, up to about 20 feet.
If you examine this other thread below, you can see a small cardboard box that could enclose both the Cyton and dongle. Be sure the circuit traces do not touch / short each other out. It then may also be possible to wrap a layer of aluminum foil around such a box, which could prevent external Bluetooth from entering.
https://openbci.com/forum/index.php?p=/discussion/2392/safety-housing-for-cyton-resolved
Regards, William
Hello there,
Thanks for your quick feedback.
As you guessed right we used an Emotiv Epoc in the last performance. That being said we're not big fan of their outsourcing policy regarding our data, thus OpenBCI seems to be a great choice.
Using a Bluetooth repeater close to the cyton board seems to be one option, but it's still wireless communication.
Plugin the computer directly to Cyton with a long USB cable could be another wired option, but carrying a USB signal over a long distance isn't recommended. Thus à shielded Ethernet cable (cat 6) plugged to some sort of Cyton Shield seem to be the only good wired option for our need.
As Cyton seems to be based on an Arduino-compatible board, do you think an arduino ethernet shield (like this one ) will do the job if I do some custom wiring ?
All the best
I did not suggest a "Bluetooth repeater", but using the actual Cyton dongle on an extension cord. Since the actual data rate of the serial data on the usb-serial port is fairly slow (~100K bits/sec), it should not be pushing the usb spec excessively. And at least a 20 foot cable should work. The dongle is only usb-2, not usb-3 speeds. I also mentioned enclosure and shielding options.
The shield you reference is NOT designed to mate physically or logically or firmware wise with Cyton. You can certainly experiment with lashing it up. But then you have the whole area of firmware mods, which would be daunting to say the least.
What about the suggestion of just reducing WIFI / Bluetooth usage in the room for your performance? If it worked for EPOC, it should work for OpenBCI.
Also see this, 50 feet.
https://www.amazon.com/PTC-USB2-0-Active-Repeater-Extension/dp/B0040IG1A6
I'm sorry If I misunderstood.
What do you recommend then if I want a physical connection between my Cyton board and my computer unit ?
All the best
There is no easy "physical connection" option. Did you see the 50 foot usb cable link above? Many positive reviews on Amazon, only $25 and your problem is likely solved. Also see previous comments about box for Cyton, and shielding around box.