def start(self, device, node_id):
if node_id < 1 or node_id > 127:
raise CANopenException('Node identifier needs to be in the range of 1 to 127.')
print('Starting CANopen device with Node ID %d(0x%02X)' % (node_id, node_id))
self.event.start()
self.driver = SocketCAN(device=device)
self.receiver.start()
self.timer.start()
self.nmt = NMT(canopen=self, node_id=node_id)
# Bootup message
data = bytearray()
data.append(self.nmt.operatingState)
self.send(0x700 + self.nmt.node_id, data)
self.nmt.operatingState = self.nmt.OPERATIONAL
class CANopen:
def __init__(self):
self.driver = None
self.event = Event()
self.receiver_alive = True
self.receiver = Thread(target=self.run)
self.timer = Timer()
self.nmt = None
def start(self, device, node_id):
if node_id < 1 or node_id > 127:
raise CANopenException('Node identifier needs to be in the range of 1 to 127.')
print('Starting CANopen device with Node ID %d(0x%02X)' % (node_id, node_id))
self.event.start()
self.driver = SocketCAN(device=device)
self.receiver.start()
self.timer.start()
self.nmt = NMT(canopen=self, node_id=node_id)
# Bootup message
data = bytearray()
data.append(self.nmt.operatingState)
self.send(0x700 + self.nmt.node_id, data)
self.nmt.operatingState = self.nmt.OPERATIONAL
def send(self, node_id, data):
self.driver.send(node_id, data)
def register(self, handler):
self.event += handler
def run(self):
while self.receiver_alive:
try:
# TODO do not block, then we can not terminate
message = self.driver.recv()
# TODO use new thread to emit events
self.event(message=message)
except CANopenException:
print('Problem receiving data.')
def stop(self):
print('Stopping CANopen device')
self.nmt.delete()
self.timer.stop()
self.receiver_alive = False
self.driver.close()
self.receiver.join()
self.event.stop()
def SDOupload(self, node_id, index, subindex, type, value):
# only expedited yet
if len(value) > 4:
raise CANopenException('Can not upload more than 4 bytes currently.')
data = bytearray()
# command byte
data.append(0x23 | (4 - len(data)) << 2)
# index LSB
data.append(index & 0xff)
data.append((index >> 8) & 0xff)
# sub-index
data.append(subindex)
# data TODO LSB
data.append(value)
receive = SDOResponse()
self.event += receive.receive()
try:
self.send(0x580 + node_id, data)
return receive.get()
finally:
self.event -= receive.receive()
def SDOread(self, node_id, index, subindex, type):
return 0
