goelster is a CAN bus utility for interacting with Elster/Kromschröder CAN bus devices. Popular heat pumps like Stiebel Eltron or WPM Wärmepumpenmanager use this protocol.
goelster is based on the work of Jürg Müller and his can_progs package. This tool would not have been possible without the work and efforts of Jürg.
Prerequisites
goelster requires Go 1.11 for compiling. Earlier versions of go can be used if required modules are installed.
Go can be downloaded from golang.org/dl/. For Raspbian chose linux-armv6l.tar.gz and move to /usr/local.
Usage
goelster command line is similar to the can_progs package.
Listening on the CAN bus
Listening on the CAN bus is similar to the can_logger tool from the can_progs package. Listing possible with the following command:
goelster <can dev>
Scanning a device
For scanning, goelster will try to read every single elster register. For details on all defined readings see Elster reading definitions source github:
goelster <can dev> <sender can id>
Reading a device register
goelster <can dev> <sender can id>.<receiver can id>
The value will be decoded as defined in the Elster reading definitions.
Writing a device register
Writing supports two modes. For compatibility with can_scan it is possible to write raw binary values:
goelster <can dev> <sender can id>.<receiver can id>.<raw value>
Example: set EINSTELL_SPEICHERSOLLTEMP2 to 42°C
goelster slcan0 680 180.0a06.01a4
It is also possible to specify numeric values:
goelster <can dev> <sender can id>.<receiver can id> <value>
Example: set EINSTELL_SPEICHERSOLLTEMP2 to 42°C
goelster slcan0 680 180.0a06 42
The value will be encoded as defined in the Elster reading definitions.