wmbusmeters

The program receives and decodes C1 or T1 telegrams (using the wireless mbus protocol) to acquire utility meter readings.

OS/Compiler	Status
Linux G++

wmbusmeters version: 0.6
Usage: wmbusmeters {options} (auto | /dev/ttyUSBx)] { [meter_name] [meter_type] [meter_id] [meter_key] }*

Add more meter quadruplets to listen to more meters.
Add --verbose for detailed debug information.
    --robot or --robot=json for json output.
    --robot=fields for semicolon separated fields.
    --separator=X change field separator to X.
    --meterfiles=dir to create status files below dir,
          named dir/meter_name, containing the latest reading.
    --meterfiles defaults dir to /tmp.
    --c1 or --t1 listen to C1 or T1 messages
    --shell=cmd invokes cmd with env variables containing the latest reading.
    --shellenvs list the env variables available for the meter.
    --oneshot wait for an update from each meter, then quit.
    --exitafter=20h program exits after running for twenty hours,
          or 10m for ten minutes or 5s for five seconds.

Specifying auto as the device will automatically look for usb
wmbus dongles on /dev/im871a and /dev/amb8465.

The meter types: multical21,flowiq3100 (water meters) are supported.
The meter types: multical302 (heat), omnipower (electricity) and supercom587 (water)
are work in progress.

Currently the meters are hardcoded for the European default setting that specifies what extra data is sent in the telegrams. If someone has a non-default meter that sends other extra data, then this will show up as a warning when a long telegram is received (but not in the short telegrams, where wrong values might be printed instead!). If this happens to someone, then we need to implement a way to pass the meter configuration as a parameter.

Actually, the mbus (and consequently the wmbus) protocol is a standard that is self-describing. Thus in reality it should not be necessary to supply exactly which kind of meter we expect for a given id. This should be possible to figure out when we receive the first telegram.

Thus, strictly speaking, it should not be necessary to specify the exact meter type. A more generic meter type might be just "water", "heat" or electricity. But for the moment, the separation of meter types will remain in the code. Thus even though the meter type right now is named multical302, the other heat meters (multical-402 and multical-602) might be compatible as well. The same is true for the omnipower meter type, which might include the electricity meters Kamstrup-162 Kamstrup-382, Kamstrup-351 etc).

No meter quadruplets means listen for telegram traffic and print any id heard, but you have to specify if you want to listen using radio mode C1 or T1. E.g.

wmbusmeters --t1 /dev/ttyUSB0

You can listen to multiple meters as long as they all require the same radio mode C1 or T1. So (currently) you cannot listen to a multical21 and a supercom587 with a single dongle at the same time.

Usage examples

wmbusmeters /dev/ttyUSB0 MyTapWater multical21 12345678 00112233445566778899AABBCCDDEEFF

wmbusmeters will detect which kind of dongle is connected to /dev/ttyUSB0. It can be either an IMST 871a dongle or an Amber Wireless AMB8465. If you have setup the udev rules below, then you can use auto instead of /dev/ttyUSB0.

Example output:

MyTapWater 12345678 6.388 m3 6.377 m3 DRY(dry 22-31 days) 2018-03-05 12:02.50

Example robot json output:

wmbusmeters --robot=json auto MyTapWater multical21 12345678 00112233445566778899AABBCCDDEEFF MyHeater multical302 22222222 00112233445566778899AABBCCDDEEFF

{"media":"cold water","meter":"multical21","name":"MyTapWater","id":"12345678","total_m3":6.388,"target_m3":6.377,"current_status":"DRY","time_dry":"22-31 days","time_reversed":"","time_leaking":"","time_bursting":"","timestamp":"2018-02-08T09:07:22Z"}

{"media":"heat","meter":"multical302","name":"MyHeater","id":"22222222","total_kwh":0.000,"total_volume_m3":0.000,"current_kw":"0.000","timestamp":"2018-02-08T09:07:22Z"}

Example robot fields output:

wmbusmeters --robot=fields auto GreenhouseWater multical21 33333333 ""

GreenhouseTapWater;33333333;9999.099;77.712;;2018-03-05 12:10.24

Eaxmple of using the shell command to publish to MQTT:

wmbusmeters --shell='HOME=/home/you mosquitto_pub -h localhost -t water -m "$METER_JSON"' auto GreenhouseWater multical21 33333333 ""

Eaxmple of using the shell command to inject data into postgresql database:

wmbusmeters --shell="psql waterreadings -c \"insert into readings values ('\$METER_ID',\$METER_TOTAL_M3,'\$METER_TIMESTAMP') \" " auto MyColdWater multical21 12345678 ""

You can have multiple shell commands and they will be executed in the order you gave them on the commandline. Note that to single quotes around the command is necessary to pass the env variable names into wmbusmeters.

You can use --debug to get both verbose output and the actual data bytes sent back and forth with the wmbus usb dongle.

If the meter does not use encryption of its meter data, then enter an empty key on the command line. (you must enter "")

wmbusmeters --robot --meterfiles auto MyTapWater multical21 12345678 ""

You can run wmbusmeters with --logtelegrams to get log output that can be placed in a simulation.txt file. You can then run wmbusmeter and instead of auto (or an usb device) provide the simulationt.xt file as argument. See test.sh for more info.

Builds and runs on GNU/Linux:

make && make test

Binary generated: ./build/wmbusmeters

make HOST=arm

Binary generated: ./build_arm/wmbusmeters

make DEBUG=true

Binary generated: ./build_debug/wmbusmeters

make DEBUG=true HOST=arm

Binary generated: ./build_arm_debug/wmbusmeters

System configuration

Add yourself to the dialout group to get access to the newly plugged in im871A USB stick. Or even better, add this udev rule:

Create the file: /etc/udev/rules.d/99-usb-serial.rules with the content

SUBSYSTEM=="tty", ATTRS{idVendor}=="10c4", ATTRS{idProduct}=="ea60", SYMLINK+="im871a",MODE="0660", GROUP="yourowngroup"
SUBSYSTEM=="tty", ATTRS{idVendor}=="0403", ATTRS{idProduct}=="6001", SYMLINK+="amb8465",MODE="0660", GROUP="yourowngroup"

When you insert the wmbus USB dongle, a properly named symlink will be created: either /dev/im871a or /dev/amb8465. These symlinks are necessary if you want to pass "auto" to wmbusmeters instead of the exact serial port /dev/ttyUSBx.

Source code

The source code is modular and it should be relatively straightforward to add more receivers and meters.

Read for example the text file: HowToAddaNewMeter.txt

Good documents on the wireless mbus protocol:

http://www.m-bus.com/files/w4b21021.pdf

https://www.infineon.com/dgdl/TDA5340_AN_WMBus_v1.0.pdf

http://fastforward.ag/downloads/docu/FAST_EnergyCam-Protocol-wirelessMBUS.pdf

http://www.multical.hu/WiredMBus-water.pdf

http://uu.diva-portal.org/smash/get/diva2:847898/FULLTEXT02.pdf

http://projekter.aau.dk/projekter/da/studentthesis/wireless-mbus-based-extremely-low-power-protocol-for-wireless-communication-with-water-meters(6e1139d5-6f24-4b8a-a727-9bc108012bcc).html

The AES source code is copied from:

https://github.com/kokke/tiny-AES128-C

The following other github projects were of great help:

https://github.com/ffcrg/ecpiww

https://github.com/tobiasrask/wmbus-client

https://github.com/CBrunsch/scambus/

TODO: CRC checks are still missing. If the wrong AES key is supplied you probably get zero readings and sometimes warnings about wrong type of frames.

There is also a lot of wmbus protocol implementation details that probably are missing. They will be added to the program as we figure out how the meters send their data.