Android Open Source - OpenBCI-AndroidApp Save Bytes To File

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License

The source code is released under:

Copyright (c) 2014 OpenBCI(TM) Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Softwa...

Java Source Code

/* Copyright (c) 2014 OpenBCI
 * See the file license.txt for copying permission.
 * *///from ww w.  j  a va2 s  .c o m

package com.openbci.BLE;

import java.io.DataOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Arrays;

import android.os.AsyncTask;
import android.os.Environment;
import android.util.Log;

public class SaveBytesToFile extends AsyncTask<byte[], Void, Void> {

  @Override
  protected Void doInBackground(byte[]... arduinoData) {
    // Get file name for current session
    String filename = new String(arduinoData[0]);
    // Store data from RFduino
    byte[] packet = arduinoData[1];
    // Store packet data
    // The first byte is the sample counter
    byte sampleCounter = packet[0];
    // Next we have 6 data values 3 bytes each
    byte[] packetDataChannel1 = Arrays.copyOfRange(packet, 1, 4);
    byte[] packetDataChannel2 = Arrays.copyOfRange(packet, 4, 7);
    byte[] packetDataChannel3 = Arrays.copyOfRange(packet, 7, 10);
    byte[] packetDataChannel4 = Arrays.copyOfRange(packet, 10, 13);
    byte[] packetDataChannel5 = Arrays.copyOfRange(packet, 13, 16);
    byte[] packetDataChannel6 = Arrays.copyOfRange(packet, 16, 19);
    // The last byte is an Auxiliary byte
    byte packetDataAux = packet[19];

    // Data Conversion for File Writing
    // Get the sample number
    int sNumber = sampleCounter & 0xFF;
    String sampleNumberString = Integer.valueOf(sNumber).toString();

    // Get Channel data in micro Volts
    float[] channel = new float[6];
    channel[0] = OpenBCIDataConversion
        .convertByteToMicroVolts(packetDataChannel1);
    channel[1] = OpenBCIDataConversion
        .convertByteToMicroVolts(packetDataChannel2);
    channel[2] = OpenBCIDataConversion
        .convertByteToMicroVolts(packetDataChannel3);
    channel[3] = OpenBCIDataConversion
        .convertByteToMicroVolts(packetDataChannel4);
    channel[4] = OpenBCIDataConversion
        .convertByteToMicroVolts(packetDataChannel5);
    channel[5] = OpenBCIDataConversion
        .convertByteToMicroVolts(packetDataChannel6);

    // Get Auxiliary byte
    int auxNumber = packetDataAux & 0xFF;
    String auxNumberString = Integer.valueOf(auxNumber).toString();

    // Create the file for the current session
    File directory = new File(Environment.getExternalStorageDirectory(),
        "OpenBCI");
    File file = new File(directory, filename);
    DataOutputStream dos;
    try {
      dos = new DataOutputStream(new FileOutputStream(file.getPath(),
          true));
      dos.writeChars(sampleNumberString);
      dos.writeChars(", ");
      dos.writeChars(FormatDataForFile.convertFloatArrayToString(channel));
      dos.writeChars(auxNumberString);
      dos.write(System.getProperty("line.separator").getBytes());
      dos.close();
    } catch (FileNotFoundException e) {
      Log.e("Save to File AsyncTask", "Error finding file");
    } catch (IOException e) {
      Log.e("Save to File AsyncTask", "Error saving data");
    }
    return null;
  }

}

Java Source Code List

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