Some useful comments

A project log for ESP8266 Interrupt Driven Meter Monitor

A network node that will sit in my meter box and read meter pulses. The node will store accumulated readings based on pulses/min.

stuart gogginstuart goggin 03/10/2015 at 13:190 Comments

Monitoring TCP traffic on a Ubuntu box

nc -l -p 888

The Hardware

ESP8266 as the main controller

LM393 light sensor such as this one:

Image result for lm 393 light sensor

Desolder the sensor and remote mount it. It's just a cheap LDR. Plan is to stick it onto the LED on the meter.

Powersupply - Breadboard 3.3v 5v supply

Software Overview

Pulse Detect line to ESP8266 - I'm using GPIO in my sample circuit - but have to switch to GPIO 2 as it makes reprogramming tricky.

ESP8266 Interrrupt to pick up changes in light levels. Due to noise - need to decouple the ISR. So plan is to use a software debounce approach. A standard ISR will count the pulses - which might be several thousand per pulse. A second timer will operate every 10msec, and if the count of ISR pulses is > 1 then increment a second counter by 1. This will ensure that the circuit does not pick up noise.

The software will record pulses per minute. A minute timer will kick off and reset the pulse count. It will then open a TCPIP connection to

The data will be written to a ESP File and stored for later retrieval as required.