cemi frame

Besides ObjectServer protocol, BAOS 83x modules support working with cEMI LinkLayer messages. The KNX protocol is specified according to the OSI reference model as a set of layers. BAOS mode and LinkLayer mode works with two different layers - Application(higher) and LinkLayer(lower). Speaking by analogy, BAOS is like an all-ready for use HTTP protocol, and LinkLayer is an access to data going inside your network cables and wireless channels, it’s lower than a TCP/UDP sockets.

With BAOS you can set/get/read datapoint values, LinkLayer mode allows you not only work with group addresses but to communicate with another bus devices.


Required: redis-server.

For Debian-based distros:

sudo apt-get install redis-server


This is the main process - it connects to BAOS module via UART and provides clients with redis pub/sub api.

It is recommended to set device parameter explicitely at first launch:

llpub -d /dev/ttyS1

Default is /dev/ttyAMA0.


Implementation of KNXNet/IP gateway.


With this app you can put any device on bus into programming mode.

To put device 1.1.5 into programming mode:

llprog -m 1 -d 1.1.5

To put BAOS module into programming mode use this application without -d parameter:

llprog -m 1


Scan KNX line.

Simple one-threaded scan:

llscan -l 1.1

Parallel scan with eight threads:

llscan -l 1.1 -t 8

Save output into json file:

llscan -l 1.1 -t 16 -o scan_result.json

Scan range 1.1.1 - 1.1.10:

llscan -l 1.1 -s 1 -e 10