many simultaneous Cytons in same room [resolved]
MatthiasWill
Ger
Dear all,
we are using our OpenBCI devices in a students lab course. That means we have multiple devices running at the same time.
Recently I upgraded the firmware of the RFduinos and the Cyton board in order to use the new GUI.
Using just a single system works without any problems now. But as soon as an additional dongle is available we experience problems with our streams.
I suspected that the pairing that we used to have between dongle and board was broken in the process of updating the firmware.
I just checked that and can confirm that the pairing is not working any more. Any dongle and board are going together.
So the question is now:
How can I pair a dongle with a specific board?
Kind regards,
Matthias
Comments
Please read this section of the tutorial. Click the arrow to expand:
https://docs.openbci.com/GettingStarted/Boards/CytonGS/#5-optional-settings
First turn off all Cytons and dongles except the one you are configuring. Then use Autoscan to ensure the channel setting agrees between mainboard RFduino and the dongle RFduino. Use the other commands (channel setting) to pick a unique radio channel for that Cyton. Place an adhesive label on the Cyton and dongle with this channel number.
Now do the same procedure for each additional Cyton/dongle pair. Only have one Cyton/dongle pair powered up at a time, until you have them all on unique radio channels.
Does that make sense?
Regards, William
I bought three sets of cyton boards (with dongle) twice. I found that the dongle can connect different cyton boards.
If multiple boards are used together, will there be connection interference?
@TL730, hi. I've merged your new thread, into this existing thread. Please read comments above.
William
I'm also teaching a course with 5 systems running in the same large room. I've had 3 sets of problems:
1 - problems connecting
2 - jittery data streaming in the GUI
3 - excessive railing of the signal when it should be clean
It looks like manually setting the radio channel of each Cyton is the way to avoid #1. I will try that. For jittery data, it mentions the FTDI buffer. I can edit that. And the excessive railing could be signal quality and poor grounds. But I'm not sure about each of those. Would radio interference cause #2 and #3, or is that only in the startup phase? That is, once the Cyton is connected, if other people are streaming and connecting/disconnecting their Cytons, could that case jittery data streams and weird signal values? I will try working on the connection problems of isolating channels, but I'm trying to determine how much our other problems could be a symptom of just that first one.
Matt, hi.
First fix the overlapping radio channels issue. That will likely correct the packet loss you are seeing (jitter). The FTDI fix is essential for bypassing the default FTDI "latency timer".
'Railing' on the Ultracortex has a separate thread.
https://openbci.com/forum/index.php?p=/discussion/1481/how-to-become-de-railed
Regards, William
Also, make sure to put some distance between the dongles. Having them be right next to each other when plugged into USB ports might not be the ideal environment.
This worked well, thanks!