In a great sensible house, the explosion of low-cost WiFi and Bluetooth chips has allowed tons of of small wi-fi gadgets to manage the switches, lights, and all the pieces else required for a “sensible house” at a comparatively low worth. However what should you don’t need tons of of internet-connected gadgets in your house polluting the wi-fi spectrum and permitting potential safety holes into your community? For those who’re like [Lucas Teske], you may attain for one thing wired and use cheap and (currently) available Raspberry Pi Picos to create PicoHome.
The distinctive twist of PicoHome is that it makes use of a CAN bus for communication. One among [Lucas’] targets was to make the boards simply swappable when {hardware} failed. This meant board-to-board communication and protocols like I2C had been prone to noise (each time a relay triggered, the bus would lock up briefly). The CAN bus is designed to work in an electrically noisy surroundings.
There are two elements to the system: pico-relay and pico-input. The primary connects to a 16 relay board and may management 16 totally different 24v relays. The second has 16 optoisolators to learn from 12v-24v switches and numerous buttons all through the home. These may be positioned in a large metallic field in a central wiring location and never fear about it.
The firmware and board files are all launched below an Apache 2.0 license, however the CAN2040 library this undertaking depends on is below GPL. We lined the CAN2040 library when it was first launched, and it’s pretty to see it getting used for one thing totally surprising.