My meter from the gas company has on the last digit a small reflecting part of 3 by 3 millimeter.

This reflecting surface is located in the middle of the digit six, so every time the digit six comes around I have used 0.010 m³ Gas. I used a CNY70 light reflecting sensor to measure every time the six comes around.


(not in schema 741 power - on pin 4 and + on pin 7)
The above CNY70 schematics is generating a pulse every time the SIX digit comes around, is connected by the BC547 to the Dallas One Wire Counter (TAI8585) who collects all the pulse counts (just experiment a bit with 1K resistor). A Visual Basic program reads all the data from the Dallas One Wire Devices and writes the data to a MySQL Server!
