code: def start(self):
  		
  		self.serial_h.flushOutput()
  		self.serial_h.flushInput()
  		self.send(C1218IdentRequest())
  		data = self.recv()
  		if data[0] != 0x00:
  			self.logger.error('received incorrect response to identification service request')
  			return False
  
  		self._initialized = True
  		self.send(C1218NegotiateRequest(self.c1218_pktsize, self.c1218_nbrpkts, baudrate=9600))
  		data = self.recv()
  		if data[0] != 0x00:
  			self.logger.error('received incorrect response to negotiate service request')
  			self.stop()
  			raise C1218NegotiateError('received incorrect response to negotiate service request', data[0])
  		return True
docs: Send an identity request and then a negotiation request.