def _parseLength(self):
# read header and length
head = unpack(self._fmtLength, self._head)[0]
head = bits.bitClear(head, 15)
head = bits.bitClear(head, 14)
# head = bits.bitClear(head, 13)
# head = bits.bitClear(head, 12)
self._length = head
self._header = head >> 14
def __parse(self):
"""
Parses rawData
"""
buffer = self.__rawData
if buffer == None: return
# read header and length
archive = False
header, length = unpack("<BH", buffer[:3])
if self.isHalved(header):
archive = bits.bitTest(length, 15)
length = bits.bitClear(length, 15)
if length > len(buffer) + 5:
raise NeedMoreDataException('Not enough data in buffer')
crc = unpack("<H", buffer[length + 3:length + 5])[0]
crc_data = buffer[:length + 3]
if not self.isCorrectCrc(crc_data, crc):
raise Exception('Crc Is incorrect!')
# now let's read packet data
# but before this, check tagsdata length
body = buffer[3:length + 3]
if len(body) != length:
raise Exception('Body length Is incorrect!')
# apply new data
self.__rawDataTail = buffer[length + 5:]
self.__rawData = buffer[:length + 5]
self.__archive = archive
self.__header = header
self.__length = length
self.__body = body
self.__crc = crc
# parse packet body
self._parseBody(body)
def _parseBody(self):
"""
Parses packet's head
@return: self
"""
super(AvlDataCodec7, self)._parseBody()
self._body = self._rawData
self._params = {}
self._sensors = {}
time = self.readFrom('>L')
priority = bits.bitRangeValue(time, 30, 32)
if priority == 2:
self._sensors['sos'] = 1
time = bits.bitClear(time, 30)
time = bits.bitClear(time, 31)
self._params['time'] = datetime(2007, 1, 1) + timedelta(seconds=time)
globalMask = self.readFrom('>B')
hasGpsElement = bits.bitTest(globalMask, 0)
ioElements = []
ioElementsFormats = ['>B', '>H', '>L']
for index in range(len(ioElementsFormats)):
if bits.bitTest(globalMask, index + 1):
ioElements.append(ioElementsFormats[index])
if hasGpsElement:
mask = self.readFrom('>B')
# Latitude and longitude
if bits.bitTest(mask, 0):
self._params['latitude'] = self.readFrom('>f')
self._params['longitude'] = self.readFrom('>f')
# Altitude
if bits.bitTest(mask, 1):
self._params['altitude'] = self.readFrom('>h')
# Angle
if bits.bitTest(mask, 2):
self._params['azimuth'] = self.readFrom('>B') * 360 / 256
# Speed
if bits.bitTest(mask, 3):
self._params['speed'] = self.readFrom('>B')
# Satellites
if bits.bitTest(mask, 4):
self._params['satellitescount'] = self.readFrom('>B')
# CellID
if bits.bitTest(mask, 5):
self._params['gsm_cell_lac'] = self.readFrom('>H')
self._params['gsm_cell_id'] = self.readFrom('>H')
# Signal quality
if bits.bitTest(mask, 6):
self._params['gsm_signal_quality'] = self.readFrom('>B')
# Operator code
if bits.bitTest(mask, 7):
self._params['gsm_operator_code'] = self.readFrom('>L')
items = []
for fmt in ioElements:
cnt = self.readFrom('>B')
for i in range(cnt):
items.append({
'id': self.readFrom('>B'),
'value': self.readFrom(fmt)
})
self._parseElements(items)
self._params['sensors'] = self._sensors
self._ioElement = {
# Event IO ID – if data is acquired on event – this field
# defines which IO property has changed and generated an event.
# If data cause is not event – the value is 0.
'eventIoId': 0,
# List of IO elements
'items': items
}
return self
