getting output from a temperature sensor
Opened this issue · 4 comments
I'm trying to get data from a simple temperature sensor over the network via modbus. The device is accessible via the provided windows software, but doing it with modbus-cli would be much nicer.
The device (https://www.elen.sk/en/Products/temperature-humidity-led-displays-sensors/air-temperature-and-humidity/ths-sensor-40-poe-lan.html) has 2 registers, 0 for temperature and 10 for humidity, and I'd think I would get output like this, but I don't.
h.boetes@habocp3 ~ % modbus 10.10.11.22:502 0x0
Parsed 0 registers definitions from 1 files
h.boetes@habocp3 ~ % modbus 10.10.11.22:502 0xa
Parsed 0 registers definitions from 1 files
h.boetes@habocp3 ~ % modbus 10.10.11.22:502 0x10
Parsed 0 registers definitions from 1 files
The program uses sample template XML files like this:
<?xml version="1.0" encoding="UTF-8"?>
<elensensorconfigurator version="2.00.00">
<description>
<model>TS Lan</model>
<interface>Ethernet</interface>
<protocol>Modbus TCP</protocol>
<value>Temperature</value>
<register>0</register>
<variabletype>I = Int (2 Byte Signed):</variabletype>
<format>0.0</format>
<measurement>°C</measurement>
<lowlimit>21</lowlimit>
<highlimit>26</highlimit>
<hysteresis>0.1</hysteresis>
</description>
<settings>
<commport>No use</commport>
<baudrate>No use</baudrate>
<parity>No use</parity>
<data>No use</data>
<stopbit>No use</stopbit>
<ipaddress>192.168.0.68</ipaddress>
<ipport>502</ipport>
<slaveid>1</slaveid>
</settings>
<lng>1051</lng>
<info>
<line>THS sensor with Ethernet interface.</line>
<line></line>
<line>Temperature [°C] - external sensor connected to Ethernet LAN.</line>
<line></line>
<line>MODBUS TCP protocol.</line>
<line>Register: 0</line>
</info>
</elensensorconfigurator>What would be right way to get the proper output?
Oh yes, when I don't use a hex but decimal value, I get a timeout, am I missing something?
h.boetes@habocp3 ~ % modbus 10.10.11.22:502 0
Parsed 0 registers definitions from 1 files
Traceback (most recent call last):
File "/usr/local/bin/modbus", line 110, in <module>
main()
File "/usr/local/bin/modbus", line 103, in main
connect_to_device(args).perform_accesses(parse_accesses(args.access, definitions, args.byte_order, args.silent), definitions).close()
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/modbus_cli/modbus_tcp.py", line 63, in perform_accesses
access.read_registers_receive(self)
File "/usr/local/lib/python3.12/site-packages/modbus_cli/access.py", line 146, in read_registers_receive
words = modbus.receive(self.request)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/modbus_cli/modbus_tcp.py", line 29, in receive
header = self.receive_n(6)
^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/site-packages/modbus_cli/modbus_tcp.py", line 44, in receive_n
data += self.connection.recv(n - len(data))
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
TimeoutError: timed out
Hex addresses are not supported. Looks like nobody ever needed them. But it should at least report an error. What I think it's happening is that it tries to lookup the address as it it was a register name, and don't bother reporting an error if it's not defined.
The second error looks like a network problem, are you sure the device is reachable at that address? Have you tried ping or telnet?
Hello @favalex
Thanks for your reply. Yes, there is a web interface running on that IP which can be used to manage the device. port 502 is open and listening, but I don't know how to get a reply from it.
h.boetes@habocp3 ~ % nc 10.10.11.22 80
sdasdsa
HTTP/1.1 400 ERROR
ERROR 400
^C
Time: 0h:00m:07s
h.boetes@habocp3 ~ % nc 10.10.11.22 501
Ncat: Connection refused.
h.boetes@habocp3 ~ % nc 10.10.11.22 502
dasdasdsa
I think I'll set up a mirror port on the switch, so I can listen in on the traffic. See what that windows program is really sending.