Acer projector issue

hi all,
Permission denied: ‘/dev/ttyUSB0’ for Could you help what wrong with me? the log is as following. By the way, the serial port is ok when I run python inter-mode.

login as: pi
[email protected]’s password:
Linux raspberrypi 4.14.34-v7+ #1110 SMP Mon Apr 16 15:18:51 BST 2018 armv7l

The programs included with the Debian GNU/Linux system are free software;
the exact distribution terms for each program are described in the
individual files in /usr/share/doc/*/copyright.

Debian GNU/Linux comes with ABSOLUTELY NO WARRANTY, to the extent
permitted by applicable law.
Last login: Thu Jul 5 00:06:13 2018 from

SSH is enabled and the default password for the ‘pi’ user has not been changed.
This is a security risk - please login as the ‘pi’ user and type ‘passwd’ to set a new password.

pi@raspberrypi:~ $ cd …/homeassistant/.homeassistant/
pi@raspberrypi:/home/homeassistant/.homeassistant $ ls
automations.yaml customize.yaml home-assistant.log secrets.yaml
configuration.yaml deps home-assistant_v2.db tts
custom_components groups.yaml scripts.yaml
pi@raspberrypi:/home/homeassistant/.homeassistant $ vi home-assistant.log
2018-07-05 00:09:08 ERROR (MainThread) [] No route to resource/endpoint: http://IP_ADDRESS/led_endpoint
2018-07-05 00:09:08 ERROR (MainThread) [] No route to resource/endpoint:
2018-07-05 00:09:10 ERROR (MainThread) [homeassistant.components.switch] Error while setting up platform acer_projector1
Traceback (most recent call last):
File “/srv/homeassistant/lib/python3.5/site-packages/serial/”, line 265, in open
self.fd =, os.O_RDWR | os.O_NOCTTY | os.O_NONBLOCK)
PermissionError: [Errno 13] Permission denied: ‘/dev/ttyUSB0’

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File “/srv/homeassistant/lib/python3.5/site-packages/homeassistant/helpers/”, line 129, in _async_setup_platform
SLOW_SETUP_MAX_WAIT, loop=hass.loop)
File “/usr/lib/python3.5/asyncio/”, line 400, in wait_for
return fut.result()
File “/usr/lib/python3.5/asyncio/”, line 293, in result
raise self._exception
File “/usr/lib/python3.5/concurrent/futures/”, line 55, in run
result = self.fn(*self.args, **self.kwargs)
File “/home/homeassistant/.homeassistant/custom_components/switch/”, line 67, in setup_platform
add_devices([AcerSwitch(serial_port, name, timeout, write_timeout)], True)
File “/home/homeassistant/.homeassistant/custom_components/switch/”, line 77, in init
‘/dev/ttyUSB0’, 11520, timeout=0.5
File “/srv/homeassistant/lib/python3.5/site-packages/serial/”, line 240, in init
File “/srv/homeassistant/lib/python3.5/site-packages/serial/”, line 268, in open
raise SerialException(msg.errno, “could not open port {}: {}”.format(self._port, msg))
serial.serialutil.SerialException: [Errno 13] could not open port /dev/ttyUSB0: [Errno 13] Permission denied: ‘/dev/ttyUSB0’