# Modbus1 not working on build #675

**URL:** <https://community.openhab.org/t/modbus1-not-working-on-build-675/18865>\
**Category:** Bindings\
**Created:** [December 27, 2016, 12:30pm UTC](https://community.openhab.org/t/modbus1-not-working-on-build-675/18865 "2016-12-27T12:30:12Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![swiety](https://community.openhab.org/letter_avatar_proxy/v4/letter/s/3be4f8/32.png) [@swiety](https://community.openhab.org/u/swiety)\
**Post date:** [December 27, 2016, 12:30pm UTC](https://community.openhab.org/t/modbus1-not-working-on-build-675/18865/1 "2016-12-27T12:30:12Z")

</div>

Hello,  
i install new build and add modbus1-binding and copy configuration file from openhab2 snapshot build #651 and have error and i do not know how it fix, on build #651 modbus1 works well.

```auto
pi@raspberrypi:/opt $ ls -la /dev/ttyUSB0
crw-rw---- 1 openhab openhab 188, 0 gru 27 12:57 /dev/ttyUSB0
pi@raspberrypi:/opt $

```

```auto
2016-12-27 13:28:13.265 [INFO] [b.core.service.AbstractActiveService] - Modbus Polling Service has been started
2016-12-27 13:28:13.387 [ERROR] [et.wimpi.modbus.net.SerialConnection] - Could not get port identifier, maybe insufficient permissions. null
2016-12-27 13:28:13.429 [ERROR] [ing.ModbusSlaveConnectionFactoryImpl] - connect try 1/3 error: Could not get port identifier, maybe insufficient permissions. null. Connection SerialConnection@12b$
2016-12-27 13:28:13.466 [ERROR] [et.wimpi.modbus.net.SerialConnection] - Could not get port identifier, maybe insufficient permissions. null
2016-12-27 13:28:13.468 [ERROR] [ing.ModbusSlaveConnectionFactoryImpl] - connect try 2/3 error: Could not get port identifier, maybe insufficient permissions. null. Connection SerialConnection@12b$
2016-12-27 13:28:13.504 [ERROR] [et.wimpi.modbus.net.SerialConnection] - Could not get port identifier, maybe insufficient permissions. null
2016-12-27 13:28:13.505 [ERROR] [ing.ModbusSlaveConnectionFactoryImpl] - connect try 3/3 error: Could not get port identifier, maybe insufficient permissions. null. Connection SerialConnection@12b$
2016-12-27 13:28:13.507 [ERROR] [ing.ModbusSlaveConnectionFactoryImpl] - re-connect reached max tries 3, throwing last error: Could not get port identifier, maybe insufficient permissions. null. C$
2016-12-27 13:28:13.508 [ERROR] [ing.ModbusSlaveConnectionFactoryImpl] - Error connecting connection SerialConnection@12bc839[portName=/dev/ttyUSB0,port=<null>] for endpoint ModbusSerialSlaveEndpo$
2016-12-27 13:28:13.510 [WARN] [.binding.modbus.internal.ModbusSlave] - ModbusSlave (slave5): Error getting a new connection for endpoint ModbusSerialSlaveEndpoint@fecef4[portName=/dev/ttyUSB0]. $
2016-12-27 13:28:13.511 [WARN] [.binding.modbus.internal.ModbusSlave] - ModbusSlave (slave5) not connected -- aborting read request net.wimpi.modbus.msg.ReadMultipleRegistersRequest@84e685. Endpo$
.........

```

---

<div class="post-metadata">

**Author:** ![rossko57](https://community.openhab.org/user_avatar/community.openhab.org/rossko57/32/70263_2.png) [@rossko57](https://community.openhab.org/u/rossko57)\
**Post date:** [December 27, 2016, 2:11pm UTC](https://community.openhab.org/t/modbus1-not-working-on-build-675/18865/2 "2016-12-27T14:11:20Z")

</div>

_Possibly_ connected with serial library issues?

> [@Nrjavaserial upgrade causes "Serial Error: Port /dev/ttyACM0 does not exist"](https://community.openhab.org/t/nrjavaserial-upgrade-causes-serial-error-port-dev-ttyacm0-does-not-exist/18783/28):
>
> All, as this serial lib upgrade seems to cause more issues than it solves, I have just reverted the commit again (see [here](https://github.com/openhab/openhab-core/pull/102)). The next distro build will come with the old lib again, so that the issue here should go away.

I don’t know enough \*nix to comment