Intelligent Home Control

Intelligent House Concept is a building automation system using a star configured topology with wires to each device. Originally made by LK, but now owned by Schneider Electric and sold as "IHC Intelligent House Concept".

The system is made up of a central controller and up to 8 input modules and 16 output modules. Each input module can have 16 digital (on/off) inputs and each output module 8 digital (on/off) outputs, resulting in a total of 128 input and 128 outputs per controller.

The central controller has one point-to-point data communication wire connected to each module. The protocol between the central controller and the modules uses a 5V pulse width encoding as follows:

The above signal constantly repeats.

http://www.lk.dk/Lauritz+Knudsen/privat/det-intelligente-hjem/Fakta-om-IHC-familien.page?

...
Wikipedia