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OpenBCI / OpenBCI_GUI

A cross platform application for the OpenBCI Cyton and Ganglion. Tested on Mac, Windows and Ubuntu/Mint Linux.
MIT License
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Channel 4 of Ganglion v3 firmware produces noisy data #1200

Closed philippitts closed 11 months ago

philippitts commented 11 months ago

Problem

Channel 4 appears to produce noisy data. The data artifacts appear to be similar to those produced in the v2 version of the firmware, but this hasn't been confirmed experimentally. More information can be found in this forum post.

Channels 1-3 appear to function as expected.

This appears to be a OpenBCI GUI issue. The data comes through correctly in BrainFlow.

Below is a 12Hz sine wave on channel 4 with no filtering using the BrainFlow plot_real_time.py example.

275626514-32652499-9ee8-4c87-8551-80f2e4f6523c

Expected

Channel 4 should produce accurate results like channels 1-3 when Ganglion v3 firmware is used.

Operating System and Version

Windows 10

GUI Version

v5.2.2

Are you running the downloaded app or from Processing/VSCode?

The downloaded app

Type of OpenBCI Board

Ganglion

Console Log and Screenshots

Paste any relevant text from the console window here, as well as any helpful screenshots of the GUI.

12Hz sine wave driven through channel 4 on Ganglion v3 firmware: image

12Hz sine wave driven through channel 3 on Ganglion v3 firmware: image

philippitts commented 11 months ago

After further testing, it appears that this is actually a lower level problem and not an issue with the OpenBCI GUI itself. The problem occurs when accelerometer data is enabled. This is done by default in the GUI and not done by default in the BrainFlow plotting utility.

Keeping this issue open to include a possible BrainFlow jar update.

philippitts commented 11 months ago

Problem has been identified and the fix is isolated to a firmware update. No need to update BrainFlow. Closing this issue as no changes are required to the GUI.