Hey there, I've successfully converted just about everything in my house to with zwave sensors or homebrewed mysensors modules for lighting / temp hum, motions, etc.
The trouble I've been having is sourcing /building a multi button remote.
It's either go with a very expensive and at times not the most functional /attractive zwave device or build a clunky diy multi button MyS module that is just to large to be practical.
Has anyone taken the plunge to build a small battery powered multi button sensor? Seems the challenge is using a button array to wake the module with the single interrupt. I've been starting to dig into potentially using an i2c module but then size starts becoming an issue. I've been keeping my eye on a few projects in the open hardware group, but are still a little too hacked together. Smd soldering is easy but unfortunately I don't have the time to learn how to build a pcb from scratch.
How difficult is it to build an i2c io multiplexer? Ideally we have someone with better eagle skills than mine (close to none) that can combine emccubes mysgrowled sensor and a i2c multiplexer onto a single board
I feel this is one area we need to focus on more to make this project whole.
Anyone have projects or ideas they can throw my way. I'm going to be doing some serious digging later this year to try and make something useful to the community
@rchamp not sure if it matches what you want but these projects might be interesting if you haven't seen them, especially the discussion in the second link
I think the solution is with more advanced Ics than the atmega328.
NRF52 or SAMD (with cortex M0) can manage touch arrays with very low power consumption (at least, better than any additional touch IC using single interrupt that I know). They also exist in versions with a lot of pins if you want to use PWM to have a led on each button of your remote.
Else you can use an i2c expander, there's a wide range of choices up to something like SX1509 which can manage 16 inputs/outputs with PWM, led driving with "breathe" function, interrupt for changes on any of the I/O etc etc
If you wanted to take a dip into making your own PCB, I used an online tool called EasyEDA. I have tried Eagle in the past, but found it a bit cumbersome at times. Not to mention it has some limitations on the free version, or at least it did years ago when I tried it. I found EasyEDA quite easy to use, but then again I wasn't making anything too complex. Have a look though, you may find it easier than you think.
I would use the pin change interrupts. If you search you can find a neat hack for making PCINT work to wake up the micro from MySensors sleep loop. That gives you many interrupts to use.