recording from Cyton with Python, values stuck at 8388607

isozyesilisozyesil
edited December 2017 in Software
Hello,

I have a Cython + Daisy Board. I want record channel data using Python. However  my data stucks on those voltages. When I use the OpenBCI_GUI and turned on SRB, there is no railed or any problem. 

How can I get over from this problem?

You can see in the below a sample from recieved data. 

Thanks in advance. 

131.000000
[-8388608, 8388607, -8388608, -8388608, -8388608, -8388608, -8388608, -8388608, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607]
[104, 3904, 880]
----------------
----------------
133.000000
[-8388608, 8388607, -8388608, -8388608, -8388608, -8388608, -8388608, -8388608, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607]
[0, 0, 0
----------------
----------------
135.000000
[-8388608, 8388607, -8388608, -8388608, -8388608, -8388608, -8388608, -8388608, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607, 8388607]
[0, 0, 0]
----------------

Comments

  • wjcroftwjcroft Mount Shasta, CA
    8388607 in hex is 0x7FFFFF, which implies that your Python may be misconfigured, did you follow the tutorial?

  • isozyesilisozyesil
    Hi @wcroft, I think I did.

    When I run the test.py without putting the headset to my head, it is working normal but when I put it on Result is 8388607 :)
  • wjcroftwjcroft Mount Shasta, CA
    What did you mean when you said: "When I use the OpenBCI_GUI and turned on SRB" -- there is no problem? The default on power up should be reference on SRB2 (closest to board). Are you making some other changes to the settings?  Where are your reference and bias electrodes?

    William

  • isozyesilisozyesil
    edited December 2017


    @wjcroft As OpenBCI GUI the application that is provided by OpenBCI. When I use it,  on the hardware options there is a button for SRB On/Off buttons.  Headset works fine while SRB1  is ON ( All 16 channels).


    BIAS (Black cable) is connected to Cython Board closest the main board (if I am getting it correct, same level with board surface) at the where BIAS is written. 

    SRB1 is connected to Cython Board closest the main board at the first pin where SRB is written.

    SRB2 is connected to Daisy Board closest the main board at the first pin where SRB is written. 

    I am very very newbie and on electronics... 

    If you want to, I can send pictures of pins and screenshots from GUI later.
    Thanks 
    Sefa
  • wjcroftwjcroft Mount Shasta, CA
    Are you using a Y-cable with your Daisy? 


    BOTH SRB pins next to the board are called SRB2. The SRB pins away from the board are SRB1 and should not be used. BOTH SRB2 pins connect with the Y cable, then the output of the Y cable goes to your reference wire, which should be on one ear clip. The other ear clip to Bias.

    You DO NOT need to mess with hardware options, everything defaults to correct settings that both the GUI and Python expect.

    William
  • isozyesilisozyesil
    Hello again @wjcroft

    you can find my SRB2 and BIAS connection pictures in the below. White one is Y cable. Black One on the Cython Board is my BIAS. 

     


    If I don't turned SRB1 On, I got railed from all data. What should I do the fix it If I correct SRB and BIAS Pins correctly?

    Regards

  • wjcroftwjcroft Mount Shasta, CA
    I thought you said you were using the pins CLOSEST to the board. These photos show you are using the pins AWAY from the board. That is your problem. All pin connections should be made on the pins the lay closest to the surface of the board.
  • isozyesilisozyesil
    My reference point as close was solder locations. This is why I was thinking as closest. Sorry for that.

    I will change and try, and let you know soon. Thank you @wjcroft. 
  • isozyesilisozyesil
    @wjcroft Thank you so much!!! I was struggling with this issue such a long period and it was my fault that getting SRB1 and SRB2 different. 

    Thanks a lot again! Only Channel 15-16 coming railed now. What should I check again? :))
  • wjcroftwjcroft Mount Shasta, CA
    If individual channels are railed, you need to adjust those specific electrodes. It's possible wires may be broken, you can check continuity with an ohmmeter.
  • pushtheworldpushtheworld
    @wjcroft +1
  • zhangleizhanglei China
    @wjcroft , I read your discussion. And I want to ask your a question about EMG. I find that the data in txt in File "C:\Program Files\OpenBCI_GUI\SavedData" is very large. For example, "7239.39, 24733.61, 37785.15, -15300.68, 50106.62, 32389.17, 19340.49, -159318.77". In fact, I find the GUI's show is small. Why is the difference so great. I know that the GUI can do some job such as filter. In fact, if I do not click the filter button, the data is not large as GUI. How can I do to make the data like GUI.

    •  Thank you very much.

  • wjcroftwjcroft Mount Shasta, CA
    @zhanglei, please read,


  • zhangleizhanglei China
    Thank you。@wjcroft I have read the information.
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