Need help connecting via LSL

Known Issues and Problems with BCI2000
Post Reply
ssaxena
Posts: 5
Joined: 19 Dec 2022, 05:35

Need help connecting via LSL

Post by ssaxena » 19 Dec 2022, 07:48

Hi, I am trying to connect an OpenBCI cyton board to BCI2000 via LSL. The connection is established (as per the Operator log) but the Source Signal window is always blank (just a moving vertical line). Please help how can this issue be resolved.

mellinger
Posts: 1210
Joined: 12 Feb 2003, 11:06

Re: Need help connecting via LSL

Post by mellinger » 19 Dec 2022, 08:07

Hi, our expert is on vacation, so I will try to help you with this. If you have a moving line, this means that data is coming in. If no signal is visible, two possibilities exist: 1) there is NaN data coming in, 2) the data has a large offset. To see what is the case, please right-click on the display and enable the high pass filter. If you can see a signal then, everything is ok, you might need to adapt SourceChOffset to account for unsigned vs signed integer data.

ssaxena
Posts: 5
Joined: 19 Dec 2022, 05:35

Re: Need help connecting via LSL

Post by ssaxena » 20 Dec 2022, 06:01

Sample block size is 8 and all other signal properties are set to auto. I set filters to the following configuration: HP filter: 0.1Hz; LP filter: 30Hz; Notch filter: 50Hz. Here's a copy of the operator log:

2022-12-20T16:18:36 - Application error, P3SpellerTask::Preflight:
Invalid unit prefix "ms" in 1ms.
2022-12-20T16:18:37 - SignalSource warning, DataIOFilter::Resting: LSLADC::Process:
Data acquisition timeout.
2022-12-20T16:18:37 - SignalSource warning, DataIOFilter::Resting: LSLADC::Process:
Write buffer overflow, data loss occurred (current buffer size is 62 blocks == 1.984s), inserting NaNs -- SourceBufferSize is reasonably large, processing may be too slow to keep up with incoming data.
2022-12-20T16:18:39 - SignalSource warning, DataIOFilter::Resting:
Average block duration is off by more than 5%.
Nominal: 32.0001ms, Actual: 0.564367ms.
2022-12-20T16:19:46 - SignalSource warning, DataIOFilter::Resting: LSLADC::Process:
Write buffer overflow, data loss occurred (current buffer size is 62 blocks == 1.984s), inserting NaNs -- SourceBufferSize is reasonably large, processing may be too slow to keep up with incoming data.
2022-12-20T16:20:07 - SignalSource warning, DataIOFilter::Resting: LSLADC::Process:
Write buffer overflow, data loss occurred (current buffer size is 62 blocks == 1.984s), inserting NaNs -- SourceBufferSize is reasonably large, processing may be too slow to keep up with incoming data. (twice).
2022-12-20T16:20:07 - SignalSource warning, DataIOFilter::Resting:
Average block duration is off by more than 5%.
Nominal: 32.0001ms, Actual: 30.3532ms.
I only see a moving vertical line in source signal window.

ssaxena
Posts: 5
Joined: 19 Dec 2022, 05:35

Re: Need help connecting via LSL

Post by ssaxena » 23 Dec 2022, 01:30

Any suggestions??

ssaxena
Posts: 5
Joined: 19 Dec 2022, 05:35

Re: Need help connecting via LSL

Post by ssaxena » 23 Dec 2022, 04:35

mellinger wrote: 19 Dec 2022, 08:07 Hi, our expert is on vacation, so I will try to help you with this. If you have a moving line, this means that data is coming in. If no signal is visible, two possibilities exist: 1) there is NaN data coming in, 2) the data has a large offset. To see what is the case, please right-click on the display and enable the high pass filter. If you can see a signal then, everything is ok, you might need to adapt SourceChOffset to account for unsigned vs signed integer data.
This didn't work. Please see the above post. Any other suggestions?

mellinger
Posts: 1210
Joined: 12 Feb 2003, 11:06

Re: Need help connecting via LSL

Post by mellinger » 23 Dec 2022, 10:55

It seems that the source module is unable to make a connection to the OpenBCI stream.
It looks for a stream of type "EEG" which seems not to be available.

Did you compile BCI2000 yourself? If so, you might update to the latest version of the SVN source tree, and recompile. This will give you more informative error information in the LSL source module.

Also, this thread might be of interest to you:
https://openbci.com/forum/index.php?p=/ ... -in-bcilab

Post Reply

Who is online

Users browsing this forum: No registered users and 26 guests