Code used in WaterMote, a low cost wireless pulse counter reader (eg. water meter) Load this sketch on your Arduino/Moteino to read a SY310 photo reflective sensor and transmit the data to a gateway Moteino that passes it along to the host (RaspberryPi, PC, etc).

It will send a message of this format to the gateway:

GPM:1.23 GAL:1234.56 GLM:1.23

GPM=Gallons per minute (realtime water flow) GLM=Gallons last minute (gallons used last minute) GAL=Gallons used since beginning of time

It also pulses a onboard LED to signal activity:

• every pulse detected will flip the LED state
• if there's no pulse activity it will flip the LED state every 5 seconds

Records the GAL counter as a LONG in EEPROM every time it changes to avoid loss in case of a power failure. Reads it back on power up.