On: Warwalking WiFi Networks with ESP8266 IoT Module

[1024core]

> I'm just finishing up an sms messaging water detector.

Sounds interesting. I'd love to know more about it; if you could share the details with us, it would be highly appreciated.

[milge → 1024core]

Sure. I only have a short video of it working right now. Please forgive the music: https://www.instagram.com/p/BEywYH2Q6n_/

I'm using an amica nodemcu board paired with a sainrite water level sensor. It's powered off of a cell phone battery charger for now. The code is all in C. I use twilio to send texts.

The final thing I need to build is a way to wake the device up from sleep when water is detected. Doing so should let it run for a very long time. (year(s)) I have a few ideas for a solution, but have been swamped lately.

[stavros → milge]

If your sensor outputs high when it detects water, use a transistor or MOSFET to pull RST low when water is detected, and send a message.

I used that trick to make my emergency food button (a button that orders food when you press it):

https://www.stavros.io/posts/emergency-food-button/

You won't get away with not powering the detector, though, so depending on its power draw it might be moot.

[milge → stavros]

Nice writeup. Someone gave me a great idea of running an ATTiny to send a wake command to the ESP when water is detected. I'm going to try a few different ways and compare battery usage.

[1024core → milge]

I can't seem to find any info on the "sainrite water level sensor" ; could it be a typo?

[milge → 1024core]

Yes, sorry. This is the one I'm using: http://www.amazon.com/SainSmart-Sensitivity-Arduino-Mega2560...

Just search for analog water sensor and you'll see a few like this labeled by different companies. There are some that are probably cheaper.