def _handle_async(self):
"""
Handles async (usually sensor) messages form sphero,
It calls the a parser function which will call any regstered
callback for each type of data
"""
id_code = ord(self.bluetooth.receive(1))
length_msb = ord(self.bluetooth.receive(1))
length_lsb = ord(self.bluetooth.receive(1))
length = (length_msb << 8) + length_lsb
array = self._read(length, offset=3)
array[0] = id_code
array[1] = length_msb
array[2] = length_lsb
checksum = check_sum(array[0:-1])
if array[-1] != checksum:
eprint("Malfromed Packet, recieved: {0} expected: {1}".format(
array[-1], checksum))
return
else:
data = array[3:-1]
tocall = self._asyn_func.get(id_code, nothing)
thread = threading.Thread(target=tocall, args=(data, ))
thread.start()
return
def _handle_acknowledge(self):
"""
Parses response packets from sphero. Response added to a response dictionary
as a Response tuple where tuple[0] indicates success and tuple[1] is the data,
the thread waiting on the response is alerted to it via an event registered
in the response_event_lookup dictionary, and is responsible for parsing the data.
all access should be done with the response_lock.
"""
msrp = ord(self.bluetooth.receive(1))
seq = ord(self.bluetooth.receive(1))
length = ord(self.bluetooth.receive(1))
if length == 0xff:
pass
# raise Exception("NOt Implemented _MSRP: {0}".format(_msrp))
# TODO cover oxff cases
array = self._read(length, offset=3)
array[0] = msrp
array[1] = seq
array[2] = length
checksum = check_sum(array[0:-1])
if array[-1] != checksum:
eprint("Malfromed Packet, recieved: {0} expected: {1}".format(
array[-1], checksum))
return
else:
event = None
with self._response_lock:
if seq in self._response_event_lookup:
event = self._response_event_lookup[seq]
del self._response_event_lookup[seq]
else:
return
if msrp == 0:
self._responses[seq] = Response(True, array[3:length + 3 - 1])
else:
self._responses[seq] = Response(
False, _MSRP.get(msrp, "UNKNOWN ERROR"))
event.set()
def _send(self, did, cid, data, response):
"""
sends data to sphero `did` is the device id, `cid` is the virtual core id
for more information view sphero Docs.
`data` is the data to send
`response` indicates if a response is expected or not if it is it handles
working with the event system, and blocks until response is recieved,
or `self.response_time_out` elapses
"""
event = None
seq_number = 0
data_length = len(data)
if response:
with self._response_lock:
seq_number = self._seq
event = threading.Event()
self._response_event_lookup[seq_number] = event
with self._msg_lock:
self._msg[1] = _ANSWER if response else _NO_ANSWER
self._msg[2] = did
self._msg[3] = cid
self._msg[4] = seq_number
self._msg[5] = data_length + 1
self._msg[6:6 + data_length] = data
checksum = check_sum(self._msg[2:6 + data_length])
self._msg[6 + data_length] = checksum
self.bluetooth.send(buffer(self._msg[0:6 + data_length + 1]))
if response:
if event.wait(self._response_time_out):
with self._response_lock:
return self._responses[seq_number]
return Response(True, '')