Hardware

Do not mix digital and analogue outputs of the light sensor Lm393 is used to switch from low to high above the light threshold. Etc. it provides digital (binary) output. If you connect it to arduino analogue ping you mostly will read binary data with some noise. Analogue output of this sensor is bypassing lm393 and provides you a range of analogue levels depending on the light level For me a cheap 5mm round photoresistor is very sufficient as a light sensor. Just create a divider with photoresistor on bottom and fixed resistor on top. Fixed resistor should be with resistance much lower than dark resistance of the photoresistor, so you will read 1023 in a dark room

Hi. Just wanted to let you know that I've tested this with an Arduino Leonardo, with the RF24 library bundled with "My Sensors" (from GIT), MISO MOSI and SCK connected to ICSP as stated on the offcial Wiki: http://arduino.cc/en/Reference/SPI also works for the MEGA 2560, but you have to connect to the ICSP or use the 50-52 pins (if using it for the Ethernet gateway for example) Regards.

Thanks That might have been my issue. I did notice the 5v step-up LED seemed to brighten at times, which I never noticed before. This sensor is a Micro Pro 3.3v with step-up to 5v for the sensor. It is powered with a 5v 1a wall plug. Anyhow I recompiled the sketch removing the EPROM write after trying some pull down resistor values, no luck, put it back in its original location and so far it has been working fine. Will have to watch it for a while.

It's not recommended. Let the gateway handle radio<->serial communication to minimize missed messages.

Yes, but you need to reconfigure io-pins correctly. Join the discussion here: http://forum.mysensors.org/topic/115/implementing-multiple-sensors#780

Basic sensors that you are using for logging and alarm are ok. However, when starting with power/switch/dimm, then security starting to be a big issue. (Also when using the sensors to control something) I hope this boards will be sold with a big warning on that point. (I'm not negative to mysensors and using those myself, why would I else be here :). I'm just not a fan of people seeing this as a complete HA solution)

@tjay4x4 I completely understand. Until about 3-4 weeks ago I did not even know what an Arduino was. Yet, here I am creating a plugin for Indigo (I did not know about Indigo until about 8 weeks ago) and creating/testing very basic sensors. Today I started creating my first 'home-grown' sensor and guess what: You have to try it to understand it :) I know from experience that you can ask just about anything when you get stuck...

@hek: Is it technical "cannot" or legal "cannot"? From technical angle it's not walk in the park but it's been done (google z-force and open-zwave).

Fantastic.. Thanks for this.

@NotYetRated Biggest difference I see is the USB FTDI onboard, good if your are connecting to a vera or something needing the comms. If it is going to be purely a sensor node, I don't see why u need this. The pro mini has 5v and 3.3v variations, or look for switchable ones, pro mini enhancements. If you are frequently reprogramming it, then easier with the nano, I'm fine using a separate ftdi board for programming purposes.

Hi Andriej, I won't do that because I have experienced quite some issues with that frequency. Some of my neighbours use the same frequency and I have had my (kitchen) light go on and off without doing anything (or even being home) too many times with these 2 devices. That is why I decided to re-use their housing but not the technology... But, thank you for the suggestion! Cheers, Marcel