Any way to manually add a child device to an st_anything/ESP8266?

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21

What are you attaching the surface mount board to in order to solder components to it? It's not just the resistors you have on the back, is it? Your boards are going to last exactly one cycle of the battery. The ESP 8266 is very sensitive to voltage. It needs exactly 3.3 volts. It will start to drop out around 3. So, as soon as your lipo battery starts dropping, it won't work anymore. Plus, when your lipo is fully changed, the voltage is much higher than 3.3 volts. It's going to fry the board. Take a look at a NodeMCU or Wemos D1 Mini. Do you think all those extra electrical components are on there just for the fun of it? No, they have to be. These little buttons are really not going to last so you would have spent all this time for nothing.

And I don't understand how you get $7 per button. The board couldn't have been less than 3 or 4, even if you bought them from China. But then you had to buy the batters. And print the enclosure.

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22

This is the board I use: (There are holes and pads to solder to)

I use this little 3.3v regulator design:

They are about 10 for $1:

These batteries:

The 1/8th watt resisters, caps, and PLA filament are pennies.

My prototypes have been working pretty well so far. Here's hoping! :slight_smile:

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23

HubDuino/ST_Anything supports Over The Air (OTA) updates on the ESP8266 boards. This does not work with your current sketch due to the deepSpleep. However, it wouldn’t be too difficult to tweak your sketch to only deepSleep if a GPIO pin were pulled either high or low. This would allow you to temporarily disable the deepSleep to allow for an OTA Update of the sketch running on the board. Afterwards, the board would resume its current behavior. Just an idea that might make it simpler for you to maintain these devices.

24

What about one of these? Samsung SmartThings Button: https://www.amazon.com/dp/B07F8ZFFQK/ref=cm_sw_r_cp_api_i_lVRcEbRYFZHAC

Looks like there is a used one via prime for $9.99. Each button can do 3 actions (push, hold, double click). They also double as temp sensors.

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25

The power regulator you are using requires at least an input voltage of 4.3v to regulate a 3.3v output. If you look at the discharge curve of a 18650 battery, it drops below 4.3v very, VERY early in it's life-span. It only uses 4-8uA and the ESP only uses about 20uA in deep sleep. But that isn't zero. It's still going to use some of the power of your battery, further shortening the time it takes to get below 4.3v.

The regulator also maxes out at 250mA. The ESP8266 is known to pull 320mA at startup. And since you are going to be doing startup every time you press the button, this is going to put a strain on your power regulator possibly burning out rather quickly.