Eric Fossum
I needed a device to time my sprinklers, because I had been forgetting to turn them off. So I made a very simple program to turn them off after 45 minutes. Future versions will have an array of outputs, so you can run sections with one button push. Hardware: Either board should work, I used the LPC1768. You will also need a solenoid to control the water, I am testing a 12V rainbird valve with a relay and 12V power supply.
Sprinkler Timer
I needed a device to time my sprinklers, because I had been forgetting to turn them off. So I made a very simple program to turn them off after some number of minutes.
Hardware
- Tested on the LPC1768
- Either board should work
- You will also need some way of controlling the flow of water (like a solenoid valve and a relay). My test equipment:
- 12V Rainbird valve (Rain Bird 3/4-Inch Sprinkler System Automatic In-Line Valve)
- relay (SainSmart 2 channel relay)
- 12V power supply (Replacement LCD Monitor Ac Adapter 12v 5a)
- Some Button for start/stop
- Some way of powering the board (maybe someone can help me power it from the 12v supply)
Connections
Button:
- One side to pin 5
- the other to Vout
Relay:
- Vcc to Vout
- Gnd to ground
- IN1 to pin 6
Directions/Use
Do not hold button while restarting!
I have experienced negative effects during testing while the button was held on. If you have problems and suspect this you may need to reflash your chip
- The button will start the sprinkler when it is off and vice versa.
- Once started if not interrupted, the sprinkler shall run for 25 minutes.
Future
Future versions will have an array of outputs, so you can run sections with one button push.
main.cpp@1:00bc4b85976e, 2013-01-22 (annotated)
- Committer:
- fossum_13
- Date:
- Tue Jan 22 16:59:24 2013 +0000
- Revision:
- 1:00bc4b85976e
- Parent:
- 0:62d1fc93556a
Fully tested v1.0
Who changed what in which revision?
| User | Revision | Line number | New contents of line |
|---|---|---|---|
| fossum_13 | 0:62d1fc93556a | 1 | #include "mbed.h" |
| fossum_13 | 0:62d1fc93556a | 2 | #include "PinDetect.h" |
| fossum_13 | 0:62d1fc93556a | 3 | |
| fossum_13 | 1:00bc4b85976e | 4 | // Objects |
| fossum_13 | 0:62d1fc93556a | 5 | DigitalOut myLed(LED1); |
| fossum_13 | 0:62d1fc93556a | 6 | DigitalOut solenoid(p6); |
| fossum_13 | 0:62d1fc93556a | 7 | PinDetect button(p5); |
| fossum_13 | 0:62d1fc93556a | 8 | Timer timer; |
| fossum_13 | 0:62d1fc93556a | 9 | |
| fossum_13 | 1:00bc4b85976e | 10 | // Primitives |
| fossum_13 | 1:00bc4b85976e | 11 | int timeInMinutes = 25; // Timer is only good to about 30 mins! |
| fossum_13 | 1:00bc4b85976e | 12 | float halfSecond = 0.5; // LED blink rate |
| fossum_13 | 0:62d1fc93556a | 13 | |
| fossum_13 | 1:00bc4b85976e | 14 | // Interrupt function for start/stop button |
| fossum_13 | 1:00bc4b85976e | 15 | ////////////////////////////////////////////////// |
| fossum_13 | 0:62d1fc93556a | 16 | void StartStop() { |
| fossum_13 | 0:62d1fc93556a | 17 | // Enabled = !Enabled |
| fossum_13 | 0:62d1fc93556a | 18 | if(solenoid.read()) { |
| fossum_13 | 0:62d1fc93556a | 19 | // Turn off |
| fossum_13 | 0:62d1fc93556a | 20 | timer.stop(); |
| fossum_13 | 1:00bc4b85976e | 21 | solenoid = false; |
| fossum_13 | 0:62d1fc93556a | 22 | } else { |
| fossum_13 | 0:62d1fc93556a | 23 | // Turn on |
| fossum_13 | 0:62d1fc93556a | 24 | timer.reset(); |
| fossum_13 | 0:62d1fc93556a | 25 | timer.start(); |
| fossum_13 | 1:00bc4b85976e | 26 | solenoid = true; |
| fossum_13 | 0:62d1fc93556a | 27 | } |
| fossum_13 | 0:62d1fc93556a | 28 | } |
| fossum_13 | 0:62d1fc93556a | 29 | |
| fossum_13 | 1:00bc4b85976e | 30 | // Main loop |
| fossum_13 | 1:00bc4b85976e | 31 | ////////////////////////////////////////////////// |
| fossum_13 | 0:62d1fc93556a | 32 | int main() { |
| fossum_13 | 1:00bc4b85976e | 33 | // Set button interrupt w/PullDown and debounce |
| fossum_13 | 0:62d1fc93556a | 34 | button.mode(PullDown); |
| fossum_13 | 0:62d1fc93556a | 35 | button.attach_asserted_held(&StartStop); |
| fossum_13 | 1:00bc4b85976e | 36 | button.setSampleFrequency(9); |
| fossum_13 | 0:62d1fc93556a | 37 | |
| fossum_13 | 0:62d1fc93556a | 38 | // Infinite loop |
| fossum_13 | 1:00bc4b85976e | 39 | while(true) { |
| fossum_13 | 1:00bc4b85976e | 40 | // Stop if time(s) > n Mins(m) * 60(s) |
| fossum_13 | 0:62d1fc93556a | 41 | if(timer.read() > timeInMinutes * 60) { |
| fossum_13 | 1:00bc4b85976e | 42 | solenoid = false; |
| fossum_13 | 0:62d1fc93556a | 43 | timer.stop(); |
| fossum_13 | 0:62d1fc93556a | 44 | } |
| fossum_13 | 0:62d1fc93556a | 45 | |
| fossum_13 | 0:62d1fc93556a | 46 | // Slow pulse status LED when enabled |
| fossum_13 | 0:62d1fc93556a | 47 | if(solenoid.read()) |
| fossum_13 | 0:62d1fc93556a | 48 | myLed = !myLed.read(); |
| fossum_13 | 0:62d1fc93556a | 49 | else |
| fossum_13 | 1:00bc4b85976e | 50 | myLed = false; |
| fossum_13 | 0:62d1fc93556a | 51 | |
| fossum_13 | 1:00bc4b85976e | 52 | // Wait so LED pulses |
| fossum_13 | 1:00bc4b85976e | 53 | wait(halfSecond); |
| fossum_13 | 0:62d1fc93556a | 54 | } |
| fossum_13 | 0:62d1fc93556a | 55 | } |