I just received the first PCB prototype for the “Room Node”. Since this is the first version i’m counting on being forced to revise the layout multiple times before get satisfied with the result.
The heart of the Room Node is a Atmel Atmega328 microprocessor which is connected to the RS485 Home Automation bus and working in a slave mode with a Linux server as master.
I call it the “Room Node” since the idea is to have one of these in each room to be able to monitor:
- Temperature (with Maxim 1-wire DS18B20)
- Ambient Light (with a simple photocell)
- Movement / Motion (with an external IR/Microwave motion detector)
I am also planning for a number of “User Interaction” possibilities:
- LED Indicator (To indicate status / alarm state)
- Buzzer (as a complement to the LED)
- Temperature control (a linear rotary potentiometer)