Eric

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Eric
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  • metamotion_user

    Hi Eric, I am sorry to disturb but I encounter a problem using c++ sdk in my vs2017 for win32 application.

    I built the sdk using command : msbuild MetaWear.Win32.vcxproj, Then I built an win32 application project in my vs2017 and add lib and header file to my project.

    The full code is here. But it corrupted when I run the code .
    https://codeshare.io/addK4e

    Could you give me some suggestions?
    Thanks!

    April 12
  • StevenWoodward

    Hi Eric, I have two MetaWearRG boards. The one I bought 5 years ago works fine with two tablets, a Huawei tablet running Android 6 and with an older Samsung Tab3 running Android 4.4. The newer one RG, less than a year old, runs only with the older tablet and Android version. I want to purchase 20 RGs for a project, but I am concerned about which Android tablets they will work with. Any ideas? Thanks, Steve

    March 27
  • RyanM
    Hi Eric,

    In reference to pymetawear logging I am getting this error:

    libmetawear.mbl_mw_logging_download(c.board, 20,pointer(download_handler))
    ctypes.ArgumentError: argument 3: <type 'exceptions.TypeError'>: expected LP_LogDownloadHandler instance instead of LP_LogDownloadHandler

    when I run this:

    from pymetawear.mbientlab.metawear.cbindings import *

    backend = 'pygatt'
    sensor = sys.argv[1]
    c = MetaWearClient(sensor, backend)

    def progress_update_handler(self,entries_left,total_entries):
            self.updates.append(entries_left)

    def unknown_entry_handler(self, id, epoch, data, length):
            data_ptr=cast(data,POINTER(c_uint))

    libmetawear.mbl_mw_logging_start(c.board,1000)
    signal = libmetawear.mbl_mw_acc_get_acceleration_data_signal(c.board)

    c.logger_created = FnVoid_VoidP(c.logger_ready)

    libmetawear.mbl_mw_datasignal_log(signal,c.logger_created)

    time.sleep(5.0)
    libmetawear.mbl_mw_logging_stop(c.board)


    c.progress_update = FnVoid_UInt_UInt(progress_update_handler)
    c.unknown_entry = FnVoid_UByte_Long_UByteP_UByte(unknown_entry_handler)

    download_handler = LogDownloadHandler(received_progress_update =c.progress_upda$

    libmetawear.mbl_mw_logging_download(c.board, 20,pointer(download_handler))

    The following was added to client.py

        def logger_ready(self,pointer):
            self.loggers.append(pointer)


    and 
    self.loggers = [] 
    to __init__


    I suspect it has something to do with the cbindings.py file that I copied over after building the C++ API.

    Would you happen to have any insights on the fix/as to when pymetawear.logging will be up and running?

    Thanks!
    July 2017
    • RyanM
      RyanM
      Never mind, I just learned a ton about the Python interpreter and back on some hot leads
  • TomAllen


    Hi Eric,


    I am using the MetaWear CPro. I am trying both of the available apps to log my data on an iPad.



     



    I
    have a query related to sampling frequency, which seems to be a common issue. I set the required sampling
    frequency (e.g. 800 Hz) in the app, log and then download the data. However,
    when I check the time spacing in excel, it does not match the frequency which I
    set in the app. In addition, it is often inconsistent changing with time.

    I am trying to use the sensor to obtain the frequency of an oscillated object, such as a pendulum. To do this I load the acceleration data into Matlab and run an fast Fourier transform to obtain the frequency. When I do this I am using a constant sample rate, as set in the app. However, I am concerned that this might not be correct, based on the time stamp I am getting.

    Please can you clarify.

    Tom

    June 2017