def __init__(self, channel, *args, **kwargs):
"""A PCAN USB interface to CAN.
On top of the usual :class:`~can.Bus` methods provided,
the PCAN interface includes the `flash()` and `status()` methods.
:param str channel:
The can interface name. An example would be PCAN_USBBUS1
:param int bitrate:
Bitrate of channel in bit/s.
Default is 500 Kbs
"""
if channel is None or channel == '':
raise ArgumentError("Must specify a PCAN channel")
else:
self.channel_info = channel
bitrate = kwargs.get('bitrate', 500000)
pcan_bitrate = pcan_bitrate_objs.get(bitrate, PCAN_BAUD_500K)
hwtype = PCAN_TYPE_ISA
ioport = 0x02A0
interrupt = 11
self.m_objPCANBasic = PCANBasic()
self.m_PcanHandle = globals()[channel]
result = self.m_objPCANBasic.Initialize(self.m_PcanHandle,
pcan_bitrate, hwtype, ioport,
interrupt)
if result != PCAN_ERROR_OK:
raise PcanError(self._get_formatted_error(result))
if HAS_EVENTS:
self._recv_event = CreateEvent(None, 0, 0, None)
result = self.m_objPCANBasic.SetValue(self.m_PcanHandle,
PCAN_RECEIVE_EVENT,
self._recv_event)
if result != PCAN_ERROR_OK:
raise PcanError(self._get_formatted_error(result))
super(PcanBus, self).__init__(*args, **kwargs)
def start(self):
"""Starts the connection."""
self.bus = pcan.PCANBasic()
self.bus.Initialize(Channel=self.channel,
Btr0Btr1=self.b_rate,
HwType=self.hw_type,
IOPort=self.io_port,
Interrupt=self.interrupt)
self.msg_read.start()
time.sleep(1)
self.open_all(force=True)
time.sleep(1.5)
def close_finger(self, finger, velocity=None, force=True):
"""Closes single digit at specified velocity."""
velocity = self.def_vel if velocity == None else int(velocity)
finger = finger_dict[finger] if type(finger) == str else int(finger)
if self.finger_status[finger - 1] in ['closing', 'stalled close'
] and force is False:
pass
else:
CANMsg = pcan.TPCANMsg()
CANMsg.ID = self._get_send_id(finger)
CANMsg.LEN = 4
CANMsg.MSGTYPE = pcan.PCAN_MESSAGE_STANDARD
msg = self.__get_message(finger, action='close', velocity=velocity)
for i in range(CANMsg.LEN):
CANMsg.DATA[i] = int(msg[i], 16)
self.bus.Write(self.channel, CANMsg)
def stop_finger(self, finger, force=True):
"""Stops execution of digit movement."""
finger = finger_dict[finger] if type(finger) == str else int(finger)
if self.finger_status[finger - 1] is 'stop' and force is False:
pass
elif self.finger_status[finger - 1] in [
'stalled open', 'stalled closed'
] and force is False:
self.finger_status[finger - 1] = 'stop'
else:
CANMsg = pcan.TPCANMsg()
CANMsg.ID = self._get_send_id(finger)
CANMsg.LEN = 4
CANMsg.MSGTYPE = pcan.PCAN_MESSAGE_STANDARD
msg = self.__get_message(finger, action='stop', velocity=290)
for i in range(CANMsg.LEN):
CANMsg.DATA[i] = int(msg[i], 16)
self.bus.Write(self.channel, CANMsg)
class PcanBus(BusABC):
def __init__(self, channel, *args, **kwargs):
"""A PCAN USB interface to CAN.
On top of the usual :class:`~can.Bus` methods provided,
the PCAN interface includes the `flash()` and `status()` methods.
:param str channel:
The can interface name. An example would be PCAN_USBBUS1
:param int bitrate:
Bitrate of channel in bit/s.
Default is 500 Kbs
"""
if channel is None or channel == '':
raise ArgumentError("Must specify a PCAN channel")
else:
self.channel_info = channel
bitrate = kwargs.get('bitrate', 500000)
pcan_bitrate = pcan_bitrate_objs.get(bitrate, PCAN_BAUD_500K)
hwtype = PCAN_TYPE_ISA
ioport = 0x02A0
interrupt = 11
self.m_objPCANBasic = PCANBasic()
self.m_PcanHandle = globals()[channel]
result = self.m_objPCANBasic.Initialize(self.m_PcanHandle,
pcan_bitrate, hwtype, ioport,
interrupt)
if result != PCAN_ERROR_OK:
raise PcanError(self._get_formatted_error(result))
if HAS_EVENTS:
self._recv_event = CreateEvent(None, 0, 0, None)
result = self.m_objPCANBasic.SetValue(self.m_PcanHandle,
PCAN_RECEIVE_EVENT,
self._recv_event)
if result != PCAN_ERROR_OK:
raise PcanError(self._get_formatted_error(result))
super(PcanBus, self).__init__(*args, **kwargs)
def _get_formatted_error(self, error):
"""
Gets the text using the GetErrorText API function
If the function succeeds, the translated error is returned. If it fails,
a text describing the current error is returned. Multiple errors may
be present in which case their individual messages are included in the
return string, one line per error.
"""
def bits(n):
while n:
b = n & (~n + 1)
yield b
n ^= b
stsReturn = self.m_objPCANBasic.GetErrorText(error, 0)
if stsReturn[0] != PCAN_ERROR_OK:
strings = []
for b in bits(error):
stsReturn = self.m_objPCANBasic.GetErrorText(b, 0)
if stsReturn[0] != PCAN_ERROR_OK:
text = "An error occurred. Error-code's text ({0:X}h) couldn't be retrieved".format(
error)
else:
text = stsReturn[1].decode('utf-8')
strings.append(text)
complete_text = '\n'.join(strings)
else:
complete_text = stsReturn[1].decode('utf-8')
return complete_text
def status(self):
"""
Query the PCAN bus status.
:return: The status code. See values in pcan_constants.py
"""
return self.m_objPCANBasic.GetStatus(self.m_PcanHandle)
def status_is_ok(self):
"""
Convenience method to check that the bus status is OK
"""
status = self.status()
return status == PCAN_ERROR_OK
def reset(self):
# Command the PCAN driver to reset the bus after an error.
status = self.m_objPCANBasic.Reset(self.m_PcanHandle)
return status == PCAN_ERROR_OK
def recv(self, timeout=None):
if HAS_EVENTS:
# We will utilize events for the timeout handling
timeout_ms = int(timeout *
1000) if timeout is not None else INFINITE
elif timeout is not None:
# Calculate max time
end_time = timeout_clock() + timeout
log.debug("Trying to read a msg")
result = None
while result is None:
result = self.m_objPCANBasic.Read(self.m_PcanHandle)
if result[0] == PCAN_ERROR_QRCVEMPTY:
if HAS_EVENTS:
result = None
val = WaitForSingleObject(self._recv_event, timeout_ms)
if val != WAIT_OBJECT_0:
return None
elif timeout is not None and timeout_clock() >= end_time:
return None
else:
result = None
time.sleep(0.001)
elif result[0] & (PCAN_ERROR_BUSLIGHT | PCAN_ERROR_BUSHEAVY):
log.warning(self._get_formatted_error(result[0]))
return None
elif result[0] != PCAN_ERROR_OK:
raise PcanError(self._get_formatted_error(result[0]))
theMsg = result[1]
itsTimeStamp = result[2]
log.debug("Received a message")
bIsRTR = (theMsg.MSGTYPE
& PCAN_MESSAGE_RTR.value) == PCAN_MESSAGE_RTR.value
bIsExt = (theMsg.MSGTYPE
& PCAN_MESSAGE_EXTENDED.value) == PCAN_MESSAGE_EXTENDED.value
if bIsExt:
#rx_msg.id_type = ID_TYPE_EXTENDED
log.debug("CAN: Extended")
else:
#rx_msg.id_type = ID_TYPE_STANDARD
log.debug("CAN: Standard")
dlc = theMsg.LEN
timestamp = boottimeEpoch + ((itsTimeStamp.micros +
(1000 * itsTimeStamp.millis)) /
(1000.0 * 1000.0))
rx_msg = Message(timestamp=timestamp,
arbitration_id=theMsg.ID,
extended_id=bIsExt,
is_remote_frame=bIsRTR,
dlc=dlc,
data=theMsg.DATA[:dlc])
return rx_msg
def send(self, msg, timeout=None):
if msg.id_type:
msgType = PCAN_MESSAGE_EXTENDED
else:
msgType = PCAN_MESSAGE_STANDARD
# create a TPCANMsg message structure
CANMsg = TPCANMsg()
# configure the message. ID, Length of data, message type and data
CANMsg.ID = msg.arbitration_id
CANMsg.LEN = len(msg.data)
CANMsg.MSGTYPE = msgType
# if a remote frame will be sent, data bytes are not important.
if msg.is_remote_frame:
CANMsg.MSGTYPE = msgType.value | PCAN_MESSAGE_RTR.value
else:
# copy data
for i in range(CANMsg.LEN):
CANMsg.DATA[i] = msg.data[i]
log.debug("Data: %s", msg.data)
log.debug("Type: %s", type(msg.data))
result = self.m_objPCANBasic.Write(self.m_PcanHandle, CANMsg)
if result != PCAN_ERROR_OK:
raise PcanError("Failed to send: " +
self._get_formatted_error(result))
def flash(self, flash):
"""
Turn on or off flashing of the device's LED for physical
identification purposes.
"""
self.m_objPCANBasic.SetValue(self.m_PcanHandle,
PCAN_CHANNEL_IDENTIFYING, bool(flash))
def shutdown(self):
self.m_objPCANBasic.Uninitialize(self.m_PcanHandle)