text: from . import retina
  
  
  class DVSBoard(retina.Retina):
      def initialize(self):
          super(DVSBoard, self).initialize()
          
      def disconnect(self):
          super(DVSBoard, self).disconnect()
  
  if __name__ == '__main__':
      import connection
      # enable testing for both cameras
      brd1 = DVSBoard()
      brd1.connect(connection.Serial('/dev/ttyUSB0', baud=12000000))
      brd1.track_frequencies(freqs=[50, 100, 150])
      brd1.retina(True)
      brd1.show_image()
      brd1.track_spike_rate(all=(0, 0, 128, 128))
      # brd2 = DVSBoard()
      # brd2.connect(connection.Serial('/dev/ttyUSB1', baud=12000000))
      # brd2.track_frequencies(freqs=[50, 100, 150])
      # brd2.retina(True)
      # brd2.show_image()
      # brd2.track_spike_rate(all=(0, 0, 128, 128))
      
      import time
      while True:
          time.sleep(1)
  