Possible to have a Wixel sense when its pair is in range?

I want to use a pair of Wixels to light up an LED when the other Wixel is in range. Is it possible to do this with just a coin cell battery and LED attached to each Wixel? I have yet to buy them, so this is mostly theory.

I came across this post https://forum.pololu.com/t/power-saving-features/3126/1 where the guy wanted to use a Wixel and another to open and close his garage door. I’d like to do the same kind of thing, but both Wixels need to be portable.

I’d just like to make sure that I have everything figured out before I buy all of the parts. I’m getting this https://www.sparkfun.com/products/783 coin cell holder and its respective battery (https://www.sparkfun.com/products/338). They provide the 3V necessary for the Wixel. For the LEDs, Sparkfun just got these https://www.sparkfun.com/products/11450 neat things in stock, so they’ll be fun to use. Of course, I’ll get the Wixel pair from Pololu.

Because there’s no “wake on radio” feature (as per the linked post), I assume I can have it sleep for a minute, check for a signal, and then sleep again. The only problem is that if the other one is doing the same thing, but transmitting, the receiver probably won’t see the signal in that small timeframe.

Would I be better off using a regular transmitter/receiver pair like this https://www.sparkfun.com/products/10535 and an ATtiny? Or would the Wixel pair work and I’m missing something?

How would you go about doing this? Thank you in advance!


This project is possible with Wixels, but you would have to write your own Wixel app (or modify an existing one) and I am not sure how low you can get the current consumption to be. The “RF Link Transmitter - 315MHz” product you linked to has a current consumption of 8 mA according to the datasheet. How long of a battery life do you need for this project?


As for battery life, I suppose anywhere from a week and up is perfectly fine. I may look into rechargeables if needed.

I’m fine with writing the app; I’m sure I could learn. I’ve read the documentation and I have a general idea of the process. If a week or more battery life is possible with the Wixel, I’d love to use it.

What would the pseudo code for the Wixel app be? Does the “check every minute” idea work, or is there a better way?

Thanks again!

Sorry, I don’t have pseudo code for that. The more lax your timing constraints are, the more often you should be able to sleep, I think. I haven’t thought about it too much, but you can probably come up with some pattern of transmitting and receiving for both devices to follow to guarantee that there will be the right kind of overlap at some point.


Another thought: You might be able to find an accurate, low-power, real-time clock and use that for sychronization. I haven’t looked into it but this product from Macetech might work for you:

macetech.com/store/index.php?mai … caac518c53