Dinner table dimmer

 

This was the first device made for the Joshua bus .
Double side pcb is home made and designed with the good old Ultiboard.
I decided not to make de dimmer compleet in software, then you need interrupt driven zero crossing detection and a timer for the triac output.The disadvance of the software dimmer is that the cpu has not much time left to do something else. For example if you receiving a message over the Rs-485 then this will trigger the RX interrupt and the light will flash due the missing zero cross interrupts. Instead i’m using a analog dimmer with a 1wire potmeter.

Schematic