So. Now I solved the problem:
After a

sudo apt-get remove --purge evok && sudo apt-get update && sudo apt-get upgrade && sudo apt-get install evok

and with this new configuration in the evok.conf I got it:

[EXTENSION_1]
global_id = 2                                   ; Mandatory, REQUIRED TO BE UNIQUE
device_name = xG18                                 ; Mandatory
modbus_uart_port = /dev/extcomm/0/0            ; Mandatory
;neuron_uart_circuit = 1_01                   ; Optional
allow_register_access = True               ; Optional
address = 1                                           ; Optional, 
scan_frequency = 10                            ; Optional, 
scan_enabled = True                            ; Optional, 
;baud_rate = 19200                              ; Optional
;parity = N                                             ; Optional,
;stop_bits = 1                                        ; Optional

Hello Martin

I'm a little further along.
The extension is now recognized in the EVOK frontend.

But I don't have any Inputs on EVOK in the section:

Also the tx/rx led's do not blink.
I tried with several settings, but nothing works already until now.

Thank you very much Martin
Update to evok 2.3.0 is done now. The xG18.yaml is now under /etc/hwdefinitions/
The xG18 extension is connected. The RS485 bus also A-A and B-B. I made all settings via the DIP switches and configured the evok.conf. (as already described above ). Unfortunately I have no connection and the rx tx LED's are not flashing. Do I still have to configure the Modbus on the unipi?
Greetings Stefan

Hello @Martin-Kudláček
Thanks for your information. Then I will be patient a little longer.
I would like to ask you if adding the ID's of the 1 Wire temperature sensors to evok.conf has any performance advantages.
I have been trying to work on my distillery control for some time now. I have 18 pc. DS18B20 sensors on the 1 Wire bus. The update time of the sensors is sometimes not fast enough or not reliable. With a script I do a reset of the 1Wire bus every 2 minutes.

#!/bin/sh
while sleep 120; do
echo start mpoll 'date' 
mbpoll -m tcp -a 0 127.0.0.1 -t 0 -0 -r 1001 1 && mbpoll -m tcp -a 0 127.0.0.1 -t 0 -0 -r 1001 0
done

So the bus now runs reliably, but it cannot be a permanent solution. So I thought I would switch to the Modbus and use the DS1820 with the xG18 extension. I hope we have a reliable solution.

I tried to connect a xG18 over Modbus to my Neuron L503

First I updated Evok to 2.2.2, then I modified the /etc/evok.conf as follow:

; Konfiguration Brennerei

[EXTENSION_1]
global_id = 2                                                  ; Mandatory, REQUIRED TO BE UNIQUE
device_name = xG18                                             ; Mandatory
modbus_uart_port = /dev/extcomm/0/0                            ; Mandatory
;neuron_uart_circuit = 1_01                             ; Optional, allows associating extensions with specific Neuron UART-over-Modbus ports (not possible for non-Modbus UART ports, e.g. /dev/ttyUSB0 or /d$
;allow_register_access = True                   ; Optional, False default, is mandatory with third-party devices
address = 6                                                    ; Optional, 1 default
;scan_frequency = 10                                    ; Optional, 10 default, scanning frequency in [Hz]
;scan_enabled = True                                    ; Optional, True default
; Note that the following settings will be inherited by other devices sharing the same port, i.e. /dev/extcomm/0/0
;baud_rate = 19200                                              ; Optional, NEEDS UNIPI IMAGE TO WORK WITH UNIPI SERIAL PORTS! USE API TO CONFIGURE UART MANUALLY IF USING STANDARD RASPBIAN
:parity = N                                                             ; Optional, NEEDS UNIPI IMAGE TO WORK WITH UNIPI SERIAL PORTS! USE API TO CONFIGURE UART MANUALLY IF USING STANDARD RASPBIAN
;stop_bits = 1

And made the UART settings over the Evok webfrontend:

I think, I put also the DIP switches on the xG18 to the right positions, witch are 011001 (Adress. 6; 19200bps;N)

But now I find out that the file xG18.yaml is missing in the /etc/hwdefinitions directory. Could this be the problem?
I didn't found it on Github.

Kind regards Stefan

Hello Jasper

Thank's a lot for this hint. I'm searching since a while.
I have exactly the same problem with my L503. I have 12pc. DS18B20 Sensors on the 1 Wire bus and always after a huge temp change of app. 60 deg. all Data of the Temp. Sensors are frozen. Rebooting the the Neuron dosen't help. Only disconnecting from the power source helps. I brought al my sensors direct from unipi. I will test them asap.

Regards
Stefan

I installed the fhem Server on the L503. Updated EVOK to V. 2.0.7a
I try to connect with fhem to my L503. After a short time of data reading the fhem crashed. Has anyone a working configuration?

fhem.cfg:

attr global userattr cmdIcon devStateIcon devStateStyle icon sortby webCmd webCmdLabel:textField-long widgetOverride
attr global autoload_undefined_devices 1
attr global autosave 0
attr global logfile ./log/fhem-%Y-%m.log
attr global modpath .
attr global motd Messages collected while initializing FHEM:\
./log/fhem.save: Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
Please define neuron first\
\
Autosave deactivated
attr global statefile ./log/fhem.save
attr global updateInBackground 1
attr global verbose 3

define telnetPort telnet 7072 global

define WEB FHEMWEB 8083 global

define WEBphone FHEMWEB 8084 global
attr WEBphone stylesheetPrefix smallscreen

define WEBtablet FHEMWEB 8085 global
attr WEBtablet stylesheetPrefix touchpad

# Fake FileLog entry, to access the fhem log from FHEMWEB
define Logfile FileLog ./log/fhem-%Y-%m.log fakelog

define autocreate autocreate
attr autocreate filelog ./log/%NAME-%Y.log

define eventTypes eventTypes ./log/eventTypes.txt

# Disable this to avoid looking for new USB devices on startup
define initialUsbCheck notify global:INITIALIZED usb create
define neuron Neuron 192.168.1.70
attr neuron connection websockets
attr neuron room brennerei
attr neuron wsFilter input,relay

logfile:

2018.08.16 09:25:15 1: Including fhem.cfg
2018.08.16 09:25:15 3: telnetPort: port 7072 opened
2018.08.16 09:25:15 3: WEB: port 8083 opened
2018.08.16 09:25:15 3: WEBphone: port 8084 opened
2018.08.16 09:25:16 3: WEBtablet: port 8085 opened
2018.08.16 09:25:16 2: eventTypes: loaded 16 events from ./log/eventTypes.txt
2018.08.16 09:25:16 1: Including ./log/fhem.save
2018.08.16 09:25:16 1: ./log/fhem.save: Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first
Please define neuron first

2018.08.16 09:25:16 1: usb create starting
2018.08.16 09:25:16 3: Probing CUL device /dev/ttyAMA0
2018.08.16 09:25:16 3: Probing TCM_ESP3 device /dev/ttyAMA0
2018.08.16 09:25:17 3: Probing ZWDongle device /dev/ttyAMA0
2018.08.16 09:25:17 3: Probing FRM device /dev/ttyAMA0
2018.08.16 09:25:22 3: Probing CUL device /dev/ttyS0
2018.08.16 09:25:22 1: PERL WARNING: can't getattr: Input/output error at ./FHEM/DevIo.pm line 419.
2018.08.16 09:25:22 1: CUL: Can't open /dev/ttyS0: Input/output error
2018.08.16 09:25:22 1: usb create end
2018.08.16 09:25:22 0: Featurelevel: 5.8
2018.08.16 09:25:22 0: Server started with 9 defined entities (fhem.pl:17140/2018-08-14 perl:5.024001 os:linux user:fhem pid:6558)
2018.08.16 09:37:56 1: PERL WARNING: Use of uninitialized value in index at ./FHEM/00_Neuron.pm line 110.
2018.08.16 09:39:13 3: Opening neuron device 192.168.1.70:80
2018.08.16 09:39:13 3: neuron device opened
2018.08.16 09:40:23 3: Neuron_wsEncode Payload: {"cmd":"filter","devices":["input","relay"]}
2018.08.16 09:40:23 3: Neuron_wsEncode String: 81ac439b9d6a38b9fe0727b9a74825f2f11e26e9bf4661fff81c2af8f81961a1c6482af5ed1f37b9b14831fef10b3ab9c017
2018.08.16 09:43:01 3: Opening neuron device 192.168.1.70:80
2018.08.16 09:43:01 3: neuron device opened
2018.08.16 09:43:01 3: Neuron_wsDecode Incomplete:
7iI=


2018.08.16 09:45:18 2: autocreate: define NeuronPin_relay_2_03 NeuronPin relay 2_03
2018.08.16 09:45:18 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/2_03
2018.08.16 09:45:18 2: autocreate: define NeuronPin_relay_2_01 NeuronPin relay 2_01
2018.08.16 09:45:18 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/2_01
2018.08.16 09:45:18 2: autocreate: define NeuronPin_relay_2_04 NeuronPin relay 2_04
2018.08.16 09:45:18 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/2_04
2018.08.16 09:45:18 2: autocreate: define NeuronPin_relay_2_05 NeuronPin relay 2_05
2018.08.16 09:45:18 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/2_05
2018.08.16 09:45:18 2: autocreate: define NeuronPin_relay_2_02 NeuronPin relay 2_02
2018.08.16 09:45:18 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/2_02
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_03 NeuronPin relay 3_03
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_03
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_06 NeuronPin relay 3_06
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_06
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_11 NeuronPin relay 3_11
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_11
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_14 NeuronPin relay 3_14
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_14
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_10 NeuronPin relay 3_10
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_10
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_12 NeuronPin relay 3_12
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_12
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_08 NeuronPin relay 3_08
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_08
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_13 NeuronPin relay 3_13
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_13
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_01 NeuronPin relay 3_01
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_01
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_07 NeuronPin relay 3_07
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_07
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_02 NeuronPin relay 3_02
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_02
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_09 NeuronPin relay 3_09
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_09
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_04 NeuronPin relay 3_04
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_04
2018.08.16 09:45:51 2: autocreate: define NeuronPin_relay_3_05 NeuronPin relay 3_05
2018.08.16 09:45:51 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/3_05
2018.08.16 09:45:57 2: autocreate: define NeuronPin_input_1_01 NeuronPin input 1_01
2018.08.16 09:45:57 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/input/1_01
2018.08.16 09:46:21 2: autocreate: define NeuronPin_relay_1_01 NeuronPin relay 1_01
2018.08.16 09:46:21 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/1_01
2018.08.16 09:46:21 2: autocreate: define NeuronPin_relay_1_04 NeuronPin relay 1_04
2018.08.16 09:46:21 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/1_04
2018.08.16 09:46:21 2: autocreate: define NeuronPin_relay_1_02 NeuronPin relay 1_02
2018.08.16 09:46:21 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/1_02
2018.08.16 09:46:21 2: autocreate: define NeuronPin_relay_1_03 NeuronPin relay 1_03
2018.08.16 09:46:21 3: Neuron (neuron): sending GET request to url http://192.168.1.70:80/rest/relay/1_03
Undefined subroutine &main::SetExtensions called at ./FHEM/10_NeuronPin.pm line 301.
2018.08.16 09:50:28 1: Including fhem.cfg
2018.08.16 09:50:28 3: telnetPort: port 7072 opened
2018.08.16 09:50:29 3: WEB: port 8083 opened
2018.08.16 09:50:29 3: WEBphone: port 8084 opened
2018.08.16 09:50:29 3: WEBtablet: port 8085 opened
2018.08.16 09:50:29 2: eventTypes: loaded 16 events from ./log/eventTypes.txt
Undefined subroutine &main::DevIo_IsOpen called at ./FHEM/00_Neuron.pm line 531, <$fh> line 48.
2018.08.16 09:50:29 1: Including fhem.cfg
2018.08.16 09:50:29 3: telnetPort: port 7072 opened
2018.08.16 09:50:30 3: WEB: port 8083 opened
2018.08.16 09:50:30 3: WEBphone: port 8084 opened
2018.08.16 09:50:30 3: WEBtablet: port 8085 opened
2018.08.16 09:50:30 2: eventTypes: loaded 16 events from ./log/eventTypes.txt
Undefined subroutine &main::DevIo_IsOpen called at ./FHEM/00_Neuron.pm line 531, <$fh> line 48.
2018.08.16 09:50:31 1: Including fhem.cfg
2018.08.16 09:50:31 3: telnetPort: port 7072 opened
2018.08.16 09:50:31 3: WEB: port 8083 opened
2018.08.16 09:50:31 3: WEBphone: port 8084 opened
2018.08.16 09:50:31 3: WEBtablet: port 8085 opened
2018.08.16 09:50:31 2: eventTypes: loaded 16 events from ./log/eventTypes.txt
Undefined subroutine &main::DevIo_IsOpen called at ./FHEM/00_Neuron.pm line 531, <$fh> line 48.
2018.08.16 09:50:32 1: Including fhem.cfg
2018.08.16 09:50:32 3: telnetPort: port 7072 opened
2018.08.16 09:50:32 3: WEB: port 8083 opened
2018.08.16 09:50:32 3: WEBphone: port 8084 opened
2018.08.16 09:50:32 3: WEBtablet: port 8085 opened
2018.08.16 09:50:32 2: eventTypes: loaded 16 events from ./log/eventTypes.txt
Undefined subroutine &main::DevIo_IsOpen called at ./FHEM/00_Neuron.pm line 531, <$fh> line 48.
2018.08.16 09:50:33 1: Including fhem.cfg
2018.08.16 09:50:33 3: telnetPort: port 7072 opened
2018.08.16 09:50:34 3: WEB: port 8083 opened
2018.08.16 09:50:34 3: WEBphone: port 8084 opened
2018.08.16 09:50:34 3: WEBtablet: port 8085 opened
2018.08.16 09:50:34 2: eventTypes: loaded 16 events from ./log/eventTypes.txt
Undefined subroutine &main::DevIo_IsOpen called at ./FHEM/00_Neuron.pm line 531, <$fh> line 48.```