Hardware

I'm thinking of 4 PIR sensors (at each end of the two aisles). And I was thinking of a reed switch at the top of the garage door opening, and one at the door into the house. And the most convenient location for the relays controlling the lights is still a 7th location. I could put 7 wireless nodes into the garage, but then I have to run power to all of them - if 5v we still have the same long wire issues, if 120VAC then I need 7 power supplies. And the local control now involves passing messages between nodes rather than just sensing input pins and controlling output pins on the same uC. The cables supply power to the RF enabled nodes will have the same length (whether DC or AC power) as the cables going to a simple sensor, and follow the same routes. So it would be possible to do that, but at considerable cost in money and time and complexity - compared to just running a three or 4 wire cable from the main node to a $2 PIR located 1o-20 feet away, if that can easily be made to work (perhaps with the addition of a couple of small, cheap passive components. I don't know if I do need to worry about inductance, capacitance, reflections etc - that's why I'm asking. These things aren't usually specified one way or the other - you kind of need some practical experience. If those are indeed killers that cannot be fixed with a couple of passives, then I may go to the "make every sensor a full node with AC power supply and distribute AC to them instead" route. But wouldn't it be nice if I can do a $2 easy fix instead? One data point - in the Do It Yourself Christamas lighting control community, they routinely get away with sending TTL or CMOS signals quite a ways from a control unit to an optoisolator input (which controls a Triac to form a SSR which does PWM dimming of an AC circuit). The signals are just a 120 Hz PWM signal but the edge timing is at 120Hz * 256 PWM divisions. You won't find much about driving a 50' cable from a TTL or CMOS output in the datasheets, but it works in this application! It would not work if you were sending a 1 Mbps signal tho. So I have some hope that a PIR 20 feet down a cable may be able to pass back a quite usable logic signal, since it changes rather rarely. But I was hoping for some advice about the gotchas. Remember the sensors I've mentioned are magnetic reed switches, LDRs, and PIR sensors - only the latter needs power per se separate from the signal.

@daulagari Thanks :) It worked, and I have logos on my next sensor pcb.. ;) Had googled all the things that came to my mind before throwing the question in here, but I haven't seen that page before..

I apologize if you are aware of this, but are you pressing the reset button once the sketch is ready to transmit? Using a sparkfun FTDI board with knockoff pro minis, I press the reset button as soon as the first TX light blinks on serial board. If I don't: similar errors.

At the bottom of the linked article it says... Edit: [CNLohr] points out there’s a more preferred toolchain that most people have switched to. https://github.com/esp8266/esp8266-wiki/wiki/Toolchain

@C.r.a.z.y. I usually add store links directly from the build pages that is related to the example. On the main "store" there is a lot of items just for inspiration. Not all have ready-to-use MySensors Arduino examples.

@jonnyfishman said: would it be better to trigger the callback manually to pick up a response? No that won't help (as long as you call gw.process() ).

The plan is to make some LED lights without the need for a wall plug transformer, as they take up space and are fairly hard to hide away. So I'm planning to make some small 220vac->12/5vdc converters with as little components as possible. Link to plan: http://www.instructables.com/id/LED-TUBE-LGHT-AC/

Depending on what gateway you use, another solution could be to implement an MQTT client on Arduino, see http://knolleary.net/arduino-client-for-mqtt/

this is a HopeRf chipset, there is a post on supporting RFM12b already

@BulldogLowell That's exactly right. You stated it more clearly than I did. It's not a problem if you're careful in how you set up your if test but its does warrant a warning to be careful in that regard to anyone using mills() for timing their sensor reads.

@axillent Awesome!

Just got some parts and did some more testing on this so I thought I'd post a reply. The good news is there appears to be a cheap fix. As @Hoffan suggested I did some research on LED drivers. I found this one to work in my testing so far: http://www.ebay.com/itm/181113937482. I have plugged it in directly to the 12V source for 3 hours and it gets warm (maybe 100 degrees Fahrenheit) but by no means hot. I still need to connect it into my sensor and get it working with PWM. My plan is to limit the current before the MOSFET. I hope it works! Thanks again for all the help and suggestions!

ATmega328 is 8 bit.

Cool :) This is my initial sketch, but i'm still tuning it. http://forum.mysensors.org/topic/597/motion-relay-sensor-sketch-help I need to figure out only to send GW messages on an update.