Arduino Watering Interface

This Arduino sketch is used to water a vegetable patch. It is designed to interface with another program over a serial connection. It will not water the garden on its own.

I use it to water a vegetable patch with a Golang application.

Features

• Send moisture readings on demand
• Send water outlet states on demand
• Set water outlet states on demand
• Automatically shut off water outlets after a period of time, a failsafe for broken communications
• Heartbeat signal
• Per sensor configurable moisture maps

Commands

a # All water outlets off
b # All water outlets on
c # Outlet #1 on
d # Outlet #1 off
e # Outlet #2 on
f # Outlet #2 off
g # Outlet #3 on
h # Outlet #3 off
i # Outlet #4 on
j # Outlet #4 off
k # Request sensor readings
l # Request water outlet states

Responses

Moisture sensors

Example/fake data

READINGS_START
MS:1:700:44 # MS:ID:RAW:PERCENTAGE
MS:2:333:22
MS:3:333:22
MS:4:333:22
MS:5:333:22
MS:6:333:22
READINGS_END

Water outlet states

Note: REAL_STATE and SET_STATE should always match. REAL_STATE is the current digitalRead() of the pin, and SET_STATE is what the Arduino should have set the pin to.

OUTLETS_START
WO:1:0:0 # WO:ID:REAL_STATE:SET_STATE (1 = on, 0 = off)
WO:2:1:1
WO:3:0:0
WO:4:0:0
OUTLETS_END

Heartbeat

Heartbeats are sent on a timer, if you do not receive these after a period of time, assume the connection has died.

Be sure to read from the serial buffer, else this will fill up and stop new data being received by your program.

HEARTBEAT
HEARTBEAT
HEARTBEAT
HEARTBEAT

Dependencies

• https://github.com/contrem/arduino-timer