Just an error without a hint for the reason

[knowthelist]

knxmap -v monitor 192.168.178.20
[selector_events.py:49 - init() ] Using selector: EpollSelector
[core.py:242 - monitor() ] Starting bus monitor
[init.py:47 - parse_message() ] Parsing KnxConnectResponse
[init.py:50 - parse_message() ] Parsing KnxTunnellingRequest
[cemi.py:41 - _unpack_stream() ] unpack requires a bytes object of length 4
Traceback (most recent call last):
File "/usr/local/lib/python3.4/dist-packages/KNXmap-0.10.0-py3.4.egg/knxmap/messages/cemi.py", line 39, in _unpack_stream
return struct.unpack(fmt, buf)[0]
struct.error: unpack requires a bytes object of length 4
[base_events.py:921 - default_exception_handler() ] Exception in callback _SelectorDatagramTransport._read_ready()
handle: <Handle _SelectorDatagramTransport._read_ready()>
Traceback (most recent call last):
File "/usr/lib/python3.4/encodings/hex_codec.py", line 15, in hex_encode
return (binascii.b2a_hex(input), len(input))
TypeError: 'NoneType' does not support the buffer interface

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "/usr/lib/python3.4/asyncio/events.py", line 120, in _run
self._callback(*self._args)
File "/usr/lib/python3.4/asyncio/selector_events.py", line 932, in _read_ready
self._protocol.datagram_received(data, addr)
File "/usr/local/lib/python3.4/dist-packages/KNXmap-0.10.0-py3.4.egg/knxmap/bus/monitor.py", line 58, in datagram_received
self.print_message(knx_message)
File "/usr/local/lib/python3.4/dist-packages/KNXmap-0.10.0-py3.4.egg/knxmap/bus/monitor.py", line 115, in print_message
timestamp=codecs.encode(cemi.additional_information.get('timestamp'), 'hex'),
TypeError: encoding with 'hex' codec failed (TypeError: 'NoneType' does not support the buffer interface)
[init.py:50 - parse_message() ] Parsing KnxTunnellingRequest
[cemi.py:41 - _unpack_stream() ] unpack requires a bytes object of length 4
Traceback (most recent call last):
File "/usr/local/lib/python3.4/dist-packages/KNXmap-0.10.0-py3.4.egg/knxmap/messages/cemi.py", line 39, in _unpack_stream
return struct.unpack(fmt, buf)[0]
struct.error: unpack requires a bytes object of length 4
[base_events.py:921 - default_exception_handler() ] Exception in callback _SelectorDatagramTransport._read_ready()
handle: <Handle _SelectorDatagramTransport._read_ready()>
Traceback (most recent call last):
File "/usr/lib/python3.4/encodings/hex_codec.py", line 15, in hex_encode
return (binascii.b2a_hex(input), len(input))
TypeError: 'NoneType' does not support the buffer interface

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
File "/usr/lib/python3.4/asyncio/events.py", line 120, in _run
self._callback(*self._args)
File "/usr/lib/python3.4/asyncio/selector_events.py", line 932, in _read_ready
self._protocol.datagram_received(data, addr)
File "/usr/local/lib/python3.4/dist-packages/KNXmap-0.10.0-py3.4.egg/knxmap/bus/monitor.py", line 58, in datagram_received
self.print_message(knx_message)
File "/usr/local/lib/python3.4/dist-packages/KNXmap-0.10.0-py3.4.egg/knxmap/bus/monitor.py", line 115, in print_message
timestamp=codecs.encode(cemi.additional_information.get('timestamp'), 'hex'),
TypeError: encoding with 'hex' codec failed (TypeError: 'NoneType' does not support the buffer interface)

[fenchu]

have the same error python 3.6.5 timestamp is none:

[monitor.py:110 - print_message() ] timestamp:{'type1': 3, 'type1_length': 1, 'error_flags': 3, 'type2': 4, 'type2_length': 2, 'timestamp': None}

[cemi.py:41 -       _unpack_stream() ] unpack requires a buffer of 4 bytes
Traceback (most recent call last):
  File "/mnt/d/sensio-data/knx-test/knxmap/knxmap/messages/cemi.py", line 39, in _unpack_stream
    return struct.unpack(fmt, buf)[0]
struct.error: unpack requires a buffer of 4 bytes

[takeshixx]

Thanks for reporting this issue @knowthelist and @fenchu ! I pushed a potential fix to the develop branch (bc9f8e4) that will hopefully fix this issue. I guess timestamp could be an optional field but I'm not really sure.

May I ask with what kind of devices you got these errors (type/manufacturer)? I don't have many different devices available for testing the code, so it would be interesting to know if there are devices that have special properties.

[fenchu]

Thanks @takeshixx,
I have several of the following:
ABB IPR/S3.1.1

X.X.X.X
   Port: 3671
   MAC Address: 00:0C:DE:30:80:17
   KNX Bus Address: 1.2.4
   Additional Bus Addresses:
      1.2.9
      1.2.13
      1.2.14
      1.2.15
      1.2.16
   KNX Device Serial: 0002852AFF51
   KNX Medium: KNX TP
   Manufacturer: ABB
   Device Friendly Name: QA Test Interface
   Device Status:
      Programming Mode: disabled
      Link Layer: disabled
      Transport Layer: disabled
      Application Layer: disabled
      Serial Interface: disabled
      User Application: disabled
      BC DM: 0
   Project Install Identifier: 0
   Supported Services:
      KNXnet/IP Core
      KNXnet/IP Device Management
      KNXnet/IP Tunnelling
      KNXnet/IP Remote Configuration and Diagnosis

[takeshixx]

Thanks for sharing the info. Can you confirm that bc9f8e4 fixes your issue?

[takeshixx]

I will close this issue for now. Feel free to open a new issue if the error still occurs.