Smart Gas Meter - Battery Powered - DeepSleep

[wiredcharlie]

In this project I used a Hall Effect sensor to detect the rotation of a magnet on my gas meter.

Screen Shot 2020-10-18 at 11.35.41.png (68.17 KiB) Viewed 11833 times

By using DeepSleep and connecting the Hall Effect Sensor to the Reset pin I was able to wake the ESP at each pulse.

Code: Select all

on System#Wake do
  If [Variable#DSAllowed]=0
    TimerSet,1,30
    GPIO,2,0
  else
    TaskValueSet,1,2,1
  endif
  
 TaskValueSet,1,1,[Variable#Total]+1
endon

on Rules#Timer=1 do
 GPIO,2,1
 TaskValueSet,1,2,1
endon

On WiFi#Connected do
    SendToHTTP,xxxxxxx.co.uk,80,/gas/xxxxx.asp?[Variable#Total]
      if [Variable#DSAllowed]>0 AND [Variable#ManDSBlock]=0
         Pulse,2,0,10
         DeepSleep,0
      endif
endon

On initial power up there is 30s before DeepSleep - you can access the web interface. Obviously this is messed up if the hall sensor is triggered and the ESP is reset. ManDSBlock can also block DeepSleep for access to the web interface - http://192.168.1.62/control?cmd=taskvalueset,1,3,1

In order to catch the device when it is momentarily awake:

Code: Select all

#!/bin/bash
c=0
while [ $c -ne 1 ]; do
        ping -c 1 -i 0.1 -W 0.1 192.168.1.62
        if [ $? -eq  0 ]; then
                open http://192.168.1.62/control?cmd=taskvalueset,1,3,1
              
                c=1;
        fi
done

Allow DeepSleep again - http://192.168.1.62/control?cmd=taskvalueset,1,3,0

3144 Hall sensor is connected to 3.3v / Reset /GND and uses 2ma continuously. Power supply is 3 x Alkaline D cells.

[TD-er]

You can also use the internal pull-up resistors of the GPIO pins and set them from the pin bootstates tab as that's being loaded even before the ESP enters the loop.
So then the pin to block the reset (using a logic port I assume?) can be set high.
N.B. not all pins are usable for this, as some may toggle at boot.

Or do you use something outside the ESP to prevent the RST pin to be triggered and only by setting a pin high or low to allow a reset again?

[wiredcharlie]

You can also use the internal pull-up resistors of the GPIO pins and set them from the pin bootstates tab as that's being loaded even before the ESP enters the loop.
So then the pin to block the reset (using a logic port I assume?) can be set high.
N.B. not all pins are usable for this, as some may toggle at boot.

I hadn't thought of that!

Or do you use something outside the ESP to prevent the RST pin to be triggered and only by setting a pin high or low to allow a reset again?

No. I just turn the central heating off!