def __init__(self, packetString=None, header=None, data=None, checkCRC=True):
if (packetString != None):
# Sanity check
packetStringLength = len(packetString)
if (packetStringLength < 4):
raise InvalidPacketFormatError( \
'Impossible packet, must have a packet of at least 4 bytes but got {0}' \
.format(packetStringLength))
# The string can either be bytes or an actual string
# Force it to a string if that is the case.
if (type(packetString) == str):
packetString = packetString.encode('iso-8859-1')
# Extract the header information
self.headerLength = 4
headerString = packetString[:self.headerLength]
ctrlByte, packetLength, crc, command \
= struct.unpack(Formatting.CommandData.Header, headerString)
# Extract the value from the subsystem byte
subSystem = ctrlByte & BitMask.SubSystem
# Check if the response byte is an acknowledge
packetTypeCode = ctrlByte & BitMask.PacketType
packetType = packetTypeCode >> BitPosition.PacketType
# See if the packet is a response or a command packet
if (packetType == PacketType.Command):
raise InvalidPacketFormatError('Cannot create a response packet with the string of a command packet.')
self.header = NebHeader(subSystem, packetType, command, crc, packetLength)
# Extract the data substring
dataString = packetString[self.headerLength:self.headerLength + packetLength]
# Perform CRC of data bytes
if (checkCRC):
calculatedCRC = nebUtilities.genNebCRC8(bytearray(packetString))
if calculatedCRC != self.header.crc:
raise CRCError(calculatedCRC, self.header.crc)
if packetType == PacketType.Ack:
self.data = AckData()
else:
# Build the data object based on the subsystem and command.
self.data = ResponsePacketDataConstructors[subSystem][self.header.command](dataString)
elif (header != None and data != None):
self.header = header
self.data = data
def __init__(self, subSystem, commandType, enable=True, **kwargs):
# Logic for determining which type of command packet it is based on the header
if subSystem == SubSystem.Debug and commandType == Commands.Debug.UnitTestMotionData:
self.data = NebUnitTestMotionDataCommandData(kwargs['timestamp'], kwargs['accel'],\
kwargs['gyro'], kwargs['mag'])
elif subSystem == SubSystem.Debug and commandType == Commands.Debug.InterfaceState:
self.data = NebDataPortState(enable, kwargs['interface'])
elif subSystem == SubSystem.Motion and commandType == Commands.Motion.Downsample:
self.data = NebDownsampleCommandData(enable)
elif subSystem == SubSystem.Motion and commandType == Commands.Motion.AccRange:
self.data = NebAccRangeCommandData(enable)
elif subSystem == SubSystem.Storage and commandType == Commands.Storage.Playback :
self.data = NebFlashPlaybackCommandData(enable, kwargs['sessionID'])
elif subSystem == SubSystem.Storage and commandType == Commands.Storage.SessionInfo:
self.data = NebFlashSessionInfoCommandData(kwargs['sessionID'])
elif subSystem == SubSystem.EEPROM:
if commandType == Commands.EEPROM.Read:
self.data = NebEEPROMCommandData(False, kwargs['pageNumber'])
elif commandType == Commands.EEPROM.Write :
self.data = NebEEPROMCommandData(True, kwargs['pageNumber'], kwargs['dataBytes'])
elif subSystem == SubSystem.LED and commandType == Commands.LED.SetVal:
self.data = NebSetLEDCommandData(kwargs['ledValueTupleList'])
elif subSystem == SubSystem.LED and commandType == Commands.LED.GetVal:
self.data = NebGetLEDCommandData(kwargs['ledIndices'])
else:
self.data = NebCommandData(enable)
self.header = NebHeader(subSystem, PacketType.Command, commandType, length=len(self.data.encode()))
# Perform CRC calculation
self.header.crc = nebUtilities.crc8(bytearray(self.header.encode() + self.data.encode()))
def createResponsePacket(self, subSystem, commands, data, dataString):
crc = nebUtilities.crc8(bytearray(dataString))
header = NebHeader(subSystem, False, commands, crc, len(dataString))
responsePacket = NebResponsePacket(packetString=None, header=header, data=data, checkCRC=False)
responsePacket.header.crc = nebUtilities.genNebCRC8(bytearray(responsePacket.stringEncode()))
return responsePacket
class NebResponsePacket(object):
"""docstring for NebResponsePacket"""
@staticmethod
def createResponsePacket(self, subSystem, commands, data, dataString):
crc = nebUtilities.crc8(bytearray(dataString))
header = NebHeader(subSystem, False, commands, crc, len(dataString))
responsePacket = NebResponsePacket(packetString=None, header=header, data=data, checkCRC=False)
responsePacket.header.crc = nebUtilities.genNebCRC8(bytearray(responsePacket.stringEncode()))
return responsePacket
@classmethod
def createEmptyResponsePacket(cls, subSystem, command):
garbage = ('\000' * 16).encode('utf-8')
data = BlankData(garbage)
dataString = data.encode()
return cls.createResponsePacket(cls, subSystem, command, data, dataString)
@classmethod
def createMAGResponsePacket(cls, timestamp, mag, accel):
data = MAGData(timestamp, mag, accel)
dataString = data.encode()
return cls.createResponsePacket(cls, SubSystem.Motion, Commands.Motion.MAG, data, dataString)
@classmethod
def createIMUResponsePacket(cls, timestamp, accel, gyro):
data = IMUData(timestamp, accel, gyro)
dataString = data.encode()
return cls.createResponsePacket(cls, SubSystem.Motion, Commands.Motion.IMU, data, dataString)
@classmethod
def createEulerAngleResponsePacket(cls, timestamp, yaw, pitch, roll, demoHeading=0.0):
# Multiply the euler angle values by 10 to emulate the firmware behavior
yaw = int(yaw * 10)
pitch = int(pitch * 10)
roll = int(roll * 10)
demoHeading = int(demoHeading * 10)
garbage = '\000\000\000\000'.encode('utf-8')
dataString = struct.pack(Formatting.Data.Euler, int(timestamp), yaw, pitch, roll, demoHeading, garbage)
data = EulerAngleData(dataString)
return cls.createResponsePacket(cls, SubSystem.Motion, Commands.Motion.EulerAngle, data, dataString)
@classmethod
def createPedometerResponsePacket(cls, timestamp, stepCount, stepsPerMinute, walkingDirection):
# Multiply the walking direction value by 10 to emulate the firmware behavior
walkingDirection = int(walkingDirection * 10)
garbage = ('\000' * 7).encode('utf-8')
dataString = struct.pack(Formatting.Data.Pedometer, timestamp, stepCount, \
stepsPerMinute, walkingDirection, garbage)
data = PedometerData(dataString)
return cls.createResponsePacket(cls, SubSystem.Motion, Commands.Motion.Pedometer, data, dataString)
@classmethod
def createRotationResponsePacket(cls, timestamp, rotationCount, rpm):
garbage = ('\000' * 6).encode('utf-8')
dataString = struct.pack(Formatting.Data.RotationInfo, timestamp, rotationCount, \
rpm, garbage)
data = RotationData(dataString)
return cls.createResponsePacket(cls, SubSystem.Motion, Commands.Motion.RotationInfo, data, dataString)
def __init__(self, packetString=None, header=None, data=None, checkCRC=True):
if (packetString != None):
# Sanity check
packetStringLength = len(packetString)
if (packetStringLength < 4):
raise InvalidPacketFormatError( \
'Impossible packet, must have a packet of at least 4 bytes but got {0}' \
.format(packetStringLength))
# The string can either be bytes or an actual string
# Force it to a string if that is the case.
if (type(packetString) == str):
packetString = packetString.encode('iso-8859-1')
# Extract the header information
self.headerLength = 4
headerString = packetString[:self.headerLength]
ctrlByte, packetLength, crc, command \
= struct.unpack(Formatting.CommandData.Header, headerString)
# Extract the value from the subsystem byte
subSystem = ctrlByte & BitMask.SubSystem
# Check if the response byte is an acknowledge
packetTypeCode = ctrlByte & BitMask.PacketType
packetType = packetTypeCode >> BitPosition.PacketType
# See if the packet is a response or a command packet
if (packetType == PacketType.Command):
raise InvalidPacketFormatError('Cannot create a response packet with the string of a command packet.')
self.header = NebHeader(subSystem, packetType, command, crc, packetLength)
# Extract the data substring
dataString = packetString[self.headerLength:self.headerLength + packetLength]
# Perform CRC of data bytes
if (checkCRC):
calculatedCRC = nebUtilities.genNebCRC8(bytearray(packetString))
if calculatedCRC != self.header.crc:
raise CRCError(calculatedCRC, self.header.crc)
if packetType == PacketType.Ack:
self.data = AckData()
else:
# Build the data object based on the subsystem and command.
self.data = ResponsePacketDataConstructors[subSystem][self.header.command](dataString)
elif (header != None and data != None):
self.header = header
self.data = data
def isPacketError(self):
return self.header.packetType == PacketType.ErrorLogResp
def isPacketValid(self, packetType, subSystem, command):
return self.isPacketHeaderValid(packetType, subSystem, command)
def isPacketHeaderValid(self, packetType, subSystem, command):
valid = (self.header.packetType == packetType)
valid &= (self.header.subSystem == subSystem)
valid &= (self.header.command == command)
return valid
def stringEncode(self):
headerStringCode = self.header.encode()
dataStringCode = self.data.encode()
return headerStringCode + dataStringCode
def __str__(self):
stringFormat = "header = [{0}] data = [{1}]"
stringDescriptor = stringFormat.format(self.header, self.data)
return stringDescriptor
