I've updated the docs at home-assistant.io with sketch examples. Look at the light example.
https://home-assistant.io/components/light.mysensors/#example-sketch
It's what I used for testing during development. It adds an RGB sensor/actuator also besides a dimmer, but you can just remove any references to rgb in the sketch.
The dimmer slider will only be visible after turning on the light and clicking the entity in the gui to bring up the more info card.
This is a simple, low-cost and quick project that can get a high spouse acceptance factor.
Mirror
Remove the led strip from the aluminum profiles.
Cut the aluminum profiles and the covers to appropriate length. I used a hacksaw to cut profile+cover at the same time to ensure the got the same length.
Cut the led strips at one of the cut points using a side cutter.
Remove the old wires (they are too short to reach the box) and solder new wires.
Put the led strip back inside the aluminum profile. Note that there is a small grove at the back for the strip, this ensures that the strip is close to the profile to maximize cooling.
Glue the profiles to the mirror. I used slow-curing epoxy.
Electronics box
Drill holes in the project box for the switch (6mm) and the potentiometer (6mm should be enough but was too tight so I used 8mm).
Drill a 4mm hole for the wires to the led strips.
Upload the sketch to the Arduino
Connect the Arduino and the battery packs and put them inside the project box.
Fasten the project box using double-sided tape.
Big thanks to my wife for letting me use the action photo.
@yoshida hi!
Im not sure where you get that #9 should be A5? Looks right to me. The pin is connected to pin 9, and that is D3.
For a rotary encoder, it depends on your input - but don't you want an analog signal in? In that case you use the analog pins.
Edit: offcourse, if you use a module converting it to digital like described in the the build section you use a digital pin.
The choice of MOSFET can be tricky. Seems that irlz44n was discontinued so you may need to find one adapted to the voltage and current you want to handle.
In all the cases you need to get a logic MOSFET too, meaning that they are fully open usually around 1 to 3V.
Also I'm sort of confused as it seems to me that L7812CV is a Voltage regulator, not a MOSFET. So if you are actually using that in the MOSFET spot it will definitively not work.
Especially if you are handling high current or voltage I would recommend using one from a reputable source for your MOSFET, I recently switched from mouser / digikey / aliexpress to mostly use http://www.arrow.com as you get free regular shipping, event if you order a couple of components (no affiliation to them whatsoever).
Not yet !
In fact, the interrupt must be short enough and fast enough to be sure to not miss the RFM69 interrupts.
The code for 8 dimmers will not be really more complicated : in fact, each time we got a zero cross, we must set a timer to zero, and then wait the good amount of milliseconds to turn on the needed outputs.
So, yes, we'll have an interrupts each 10ms (each time the wave crosses the zero, to be precise !), but I think all we have to do in the interrupt handler is set the timer to zero (or to micros() ...) and then on the main loop, wait the good amount of time for each output before setting them ON.
Seems simple on paper, perhaps it will not work on the chip....
In facts, my main concern is : will the RFM interrupt be short enough to not disturb the zero crossing interrupt ?
Although, not yet tested the RFM : do we NEED the interrupt pin ? Can't we poll frequently the RFM?