ganglion: detecting MAC address

Author: jfrey-xx

README.md

@@ -19,6 +19,10 @@ This library includes the main open_bci_v3 class definition that instantiates an
 
 For additional details on connecting your board visit: http://docs.openbci.com/tutorials/01-GettingStarted
 
+### Ganglion Board
+
+The Ganglion board relies on Bluetooth Low Energy connectivity (BLE). You should also retrieve the bluepy submodule for a more up-to-date version. To do so, clone this repo with the `--recursive` flag then type `make` inside `bluepy/bluepy`. Note that you may need to run the script with root privileges to for some functionality, e.g. auto-detect MAC address.
+
 ## Audience:
 
 This python code is meant to be used by people familiar with python and programming in general. It's purpose is to allow for programmers to interface with OpenBCI technology directly, both to acquire data and to write programs that can use that data on a live setting, using python.

open_bci_ganglion.py

@@ -22,7 +22,9 @@ def handle_sample(sample):
 import sys
 import pdb
 import glob
-import bluepy
+# local bluepy should take precedence
+import sys
+sys.path.insert(0,"bluepy/bluepy")
 
 SAMPLE_RATE = 100.0  # Hz
 scale_fac_uVolts_per_count = 1200 * 8388607.0 * 1.5 * 51.0;
@@ -45,7 +47,8 @@ class OpenBCIBoard(object):
   Handle a connection to an OpenBCI board.
 
   Args:
-    port, baud, filter_data, daisy: Not used, for compatibility with v3
+    port: MAC address of the Ganglion Board. "None" to attempt auto-detect.
+    baud, filter_data, daisy: Not used, for compatibility with v3
   """
 
   def __init__(self, port=None, baud=0, filter_data=False,
@@ -54,8 +57,10 @@ def __init__(self, port=None, baud=0, filter_data=False,
     self.streaming = False
     self.timeout = timeout
 
-    print("Connecting to V3 at port %s" %(port))
-    self.ser = serial.Serial(port= port, baudrate = baud, timeout=timeout)
+    print("Looking for Ganglion board")
+    if port == None:
+      port == self.find_port()   
+    self.port = port
 
     print("Serial established...")
 
@@ -80,6 +85,58 @@ def __init__(self, port=None, baud=0, filter_data=False,
 
     #Disconnects from board when terminated
     atexit.register(self.disconnect)
+
+  def find_port(self):
+    """Detects Ganglion board MAC address -- if more than 1 around, will select first. Needs root privilege."""
+  
+    from btle import Scanner, DefaultDelegate
+
+    print("Try to detect Ganglion MAC address. NB: Turn on bluetooth and run as root for this to work!")
+    scan_time = 5
+    print("Scanning for 5 seconds nearby devices...")
+
+  #   From bluepy example
+    class ScanDelegate(DefaultDelegate):
+      def __init__(self):
+        DefaultDelegate.__init__(self)
+
+      def handleDiscovery(self, dev, isNewDev, isNewData):
+        if isNewDev:
+          print ("Discovered device: " + dev.addr)
+        elif isNewData:
+          print ("Received new data from: " + dev.addr)
+  
+    scanner = Scanner().withDelegate(ScanDelegate())
+    devices = scanner.scan(scan_time)
+
+    nb_devices = len(devices)
+    if nb_devices < 1:
+      print("No BLE devices found. Check connectivity.")
+      return ""
+    else:
+      print("Found " + str(nb_devices) + ", detecting Ganglion")
+      list_mac = []
+      list_id = []
+  
+      for dev in devices:
+        # "Ganglion" should appear inside the "value" associated to "Complete Local Name", e.g. "Ganglion-b2a6"
+        for (adtype, desc, value) in dev.getScanData():
+          if desc == "Complete Local Name" and   value.startswith("Ganglion"): 
+            list_mac.append(dev.addr)
+            list_id.append(value)
+            print("Got Ganglion: " + value + ", with MAC: " + dev.addr)
+            break
+    nb_ganglions = len(list_mac)
+  
+    if nb_ganglions < 1:
+      print("No Ganglion found ;(")
+      raise OSError('Cannot find OpenBCI Ganglion MAC address')
+
+    if nb_ganglions > 1:
+      print("Found " + str(nb_ganglions) + ", selecting first")
+
+    print("Selecting MAC address " + list_mac[0] + " for " + list_id[0])
+    return list_mac[0]
 
   def ser_write(self, b):
     """Access serial port object for write"""