fknipp/canpicker

Data collector for the CAN bus Elster protocol

canpicker

Collect data from the CAN bus using the Elster protocol

Table of Contents

• Requirements
• Installation
  • Cron Job
  • Database (optional)
  • Grafana (optional)
• Config
  • CAN bus
    • Example
    • Description
  • Data
    • Example
    • Description
  • Datasinks
    • Configuration File
    • Storing Data to MySQL
    • Sending Data to an HTTP Endpoint
    • Output to the Console
• Resources
• License

Requirements

• Python 3.9
• MySQL (optional)
• Grafana (optional)
• Raspberry Pi + CANable (or similar devices)

Installation

• Download the latest version

  wget https://github.com/fknipp/canpicker/archive/refs/heads/main.zip

• Unzip the package

  unzip canpicker-main.zip

• Change the directory

  cd canpicker-main

• Install the dependencies

  pipenv install

Cron Job

To collect the data every x minutes, it's necessary to create a cron job. This is an example to query the data every two minutes:

*/2 * * * * /home/pi/canpicker-main/bin/canpicker

Database (optional)

Execute the seed file via MySQL command line or copy the query into your MySQL shell.

Grafana (optional)

With Grafana you can create your own dashboard with widgets or use the existing template.

Config

The configuration for the CAN bus and for the data to be queried is located in config.yml. The database configuration is located in .env.

CAN bus

File: config.yml

Example

can:
  interface: can0
  sender: 680

Description

• interface: CAN bus interface
  • can0
• sender: Sender ID
  • 680

Data

File: config.yml

See http://juerg5524.ch/data/ElsterTable.inc for the indexes.

Example

data:
  - name: AUSSENTEMPERATUR
    index: 180.000c
    format: dec_val
  - name: QUELLENTEMPERATUR
    index: 180.01d4
    format: dec_val
  - name: FEHLER
    index: 180.0001

Description

• name: Name for the data point
  • AUSSENTEMPERATUR
• index: Receiver and Register separated by a dot
  • 180.000c
• format (optional):
  • dec_val
  • mil_val
  • little_endian

Datasinks

Configuration File

File: .env

Rename the .env.example file to .env and adapt it for your needs. Otherwise create it with the content for your usecase.

Storing Data to MySQL

Tha values are stored in the table sepicker. See the seed file for the data definition.

DB_DATABASE=heat-pump
DB_HOST=127.0.0.1
DB_USER=root
DB_PASSWORD=

Sending Data to an HTTP Endpoint

The data is sent as GET request to a configurable URL.

The URL template allows the substitutions:

• $timestamp for the timestamp in the ISO format
• $name for the name as configured in config.yml
• $value for the value retrieved on the CAN bus

HTTP_URL_TEMPLATE=http://loxone.local/dev/sps/io/$name/$value
HTTP_USERNAME=
HTTP_PASSWORD=

Output to the Console

This is helpful for debugging.

CONSOLE_OUT=1

Resources

• http://juerg5524.ch/list_data.php
• https://github.com/andig/goelster
• https://github.com/Andy2003/heat-pump-api
• https://github.com/danielbayerlein/sepicker
• Integration with Loxone: https://github.com/fknipp/python-can-loxone-heating-integration

License

© 2020-present Daniel Bayerlein
© 2023-present Franz Knipp

See LICENSE for details.