Help with commands to OpenBCI Cyton+Daisy

a1eks · April 2018

Hi,

I am using OpenBCI Cyton+Daisy in combination with OpenVibe. In the Acquisition Server I can add custom commands that will be sent to the board to configure channels; and for that purpose I was following the instrunctions available on http://openbci.com/index.php/forum/#/post/discussion/cyton

For our BCI application we are using 12EEG channels + 1 EMG in bipolar configuration. However, i struggle to get proper EMG data.

First I turned off channels 13 14 15 by sending:

t y u

Then, I changed I want to change gain, remove bias and change to bipolar the last 16th channel. To do so, I was sending the following command:

xI040000X

To make sure that the I (16channel) is up, i also sent:

I

But I didn't get any signal on 16th electrode, only noise! The same configuration done via OpenBCI GUI works normally.

Thnx. Aleks

wjcroft · April 2018

Aleks, hi.

Have you tried sending the commands from terminal emulator, to see if any error messages are generated? Or does the Acquistion Server show you any output during the setup process?

Note with v2, v3 firmware, you need to send groups of commands within 1 second, otherwise firmware will time out. So sending your xI040000X should be done with a paste operation. This command does look ok.

If you happen to have v1 firmware, there is an additional caution at,

http://docs.openbci.com/OpenBCI Software/04-OpenBCI_Cyton_SDK#openbci-cyton-sdk-command-set-channel-setting-commands

William

a1eks · May 2018

Sorry for the late response.

I have firmware v3.1.0. I tried using terminal emulator and commands are accepted and work well. However, with OpenVibe not really, there is no response there eighter. It seems that OpenVibe driver needs to be updated!

For this reason, I changed to LSL streaming via OpenBCI_GUI.

Now, I want to know if there is a way, eighter in Firmware or in OpenBCI_GUI to have channels 15 and 16 pre-configured for EMG (as default option)?

wjcroft · May 2018

The firmware has no built-in commands for saving a certain setting as the power-up default. But since the source of the firmware is available, you could create such a custom Cyton firmware, by looking carefully at the code and performing the setup operations in your "setup()" function.

https://github.com/OpenBCI/OpenBCI_32bit_Library

As far as I'm aware there are no commands in the GUI to save / restore settings from a file. But similarly to the firmware mod mentioned above -- instead you could modify the GUI source to mimic what happens when settings are changed.

https://github.com/OpenBCI/OpenBCI_GUI/tree/master/OpenBCI_GUI

https://github.com/OpenBCI/OpenBCI_GUI/blob/master/OpenBCI_GUI/HardwareSettingsController.pde

GUI has a setup() also,

https://github.com/OpenBCI/OpenBCI_GUI/blob/master/OpenBCI_GUI/OpenBCI_GUI.pde

Regards,

William

Help with commands to OpenBCI Cyton+Daisy

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