currently trying to make a motion sensor light that i can turn on and off with sensor detection but also have auto turn off after lets say 15 minutes if left on.
I've got it so i can turn it off and on now using motion but not sure how to have it auto turn off after a set time since delay blocks me from turning it off with motion if i try using that.
I'm thinking I'll have to use the millis function? but not sure where to start and feel like I've hit a wall so any guidance would be appreciated.
here's the code i have so far to have the sensor turn it off and on.
this old version is all i have now unfortunately, but it'll show you what i think i was trying to do? still quite new to this so it's probably embarrassingly far from right.
int led = 8;
int pir = 2;
int val;
int state = 0;
unsigned long sleep_start;
unsigned long previousMillis = 0;
void setup() {
pinMode(led, OUTPUT);
pinMode(pir, INPUT);
}
void loop() {
unsigned long currentMillis = millis();
val = digitalRead(pir);
if (sleep_start > 0 && millis() > sleep_start + 15 * 60 * 1000)
if (val == HIGH)
{
if (state == 0)
{
state = 1;
digitalWrite(led, HIGH);
sleep_start = millis();
delay (4000);
}
else {
state = 0;
sleep_start = 0;
digitalWrite(led, LOW);
delay (4000);
}
}
}
// Version YY/MM/DD Description
// 1.00 21/07/03 Functional code
// 1.01 21/07/03 Added comments
//*********************************************************************
#define movementDetection HIGH
#define LEDon HIGH
#define LEDoff LOW
#define enabled true
#define disabled false
//*********************************************************************
const byte heartbeatLED = 13;
const byte led = 8;
const byte pir = 2;
bool autoOffFlag = disabled;
byte lastPIRstate = !movementDetection;
byte val;
byte state = 0;
//Timing stuff
const unsigned long timeoutDuration = 5000; //5 seconds for testing
//const unsigned long timeoutDuration = 15 * 60 * 1000ul; //15 minutes
unsigned long heartbeatMillis;
unsigned long switchMillis;
unsigned long autoMillis;
//*********************************************************************
void setup()
{
pinMode(heartbeatLED, OUTPUT);
//turn the light OFF
digitalWrite(led, LEDoff);
pinMode(led, OUTPUT);
pinMode(pir, INPUT);
} //END of setup()
//*********************************************************************
void loop()
{
//***********************
//time to toggle the heartbeatLED ?
if (millis() - heartbeatMillis >= 500)
{
//restart the TIMER
heartbeatMillis = millis();
//toggle the LED
digitalWrite(heartbeatLED, !digitalRead(heartbeatLED));
}
//***********************
//time to check the switches ?
if (millis() - switchMillis >= 50)
{
//restart the TIMER
switchMillis = millis();
checkSwitches();
}
//***********************
//if enabled, has the auto timout duration be reached ?
if (autoOffFlag == enabled && millis() - autoMillis >= timeoutDuration)
{
//disable the TIMER
autoOffFlag = disabled;
//turn the light OFF
digitalWrite(led, LEDoff);
}
} //END of loop()
//*********************************************************************
void checkSwitches()
{
//***************************************** PIR
//
byte state = digitalRead(pir);
//***********************
//has the PIR changed state ?
if (lastPIRstate != state)
{
//update to the new state
lastPIRstate = state;
//************
//has the PIR detected movement ?
if (state == movementDetection)
{
//enable the TIMER
autoOffFlag = enabled;
//start the TIMER
autoMillis = millis();
//turn ON the light
digitalWrite(led, LEDon);
}
//PIR sensor must have timed out
else
{
//disable the TIMER
autoOffFlag = disabled;
//turn OFF the light
digitalWrite(led, LEDoff);
}
} //END of if (lastPIRstate != state)
} //END of checkSwitches()
//*********************************************************************
not entirely sure to be honest, tried to change the times on that code to stay on but couldn't keep it on for more then a few seconds, i think the sensor stays active for 3-4 seconds after activation so not sure if that could have something to do with it?
i believe so, that's why at first i was just using delay as a way to wait for the sensor to finish before i started checking for movement again but ran into the problem of figuring out an auto time off as well. sorry I'm a bit of a newbie at this, it's my first Arduino project
It is very important that the following be confirmed:
the PIR sends a HIGH (+5v) to the Arduino input when the PIR detects movement (use a DVM to confirm) OR does the sensor just close a dry relay contact ?
if movement is detected every 1 second will the PIR signal to the Arduino ever time out ?
if there was constant movement for 2 minutes then all movement stops completely, when would you like the LED to turn OFF ?
PIR sends a HIGH to the arduino when it detects movement.
looks like signal doesn't time out and I'm looking to start the auto off timer from when it first detects movement and turns on but also have the option of turning off by motion
PIR is HC-SR501 PIR Motion Sensor Module | Elektor
if movement is constantly detected it will send a HIGH signal for a long as it's there.
I'm looking to have the motion detection as just a switch to turn it on and off so i can swipe my foot and switch it on and off, but if it's on it has a timer for 15 min to auto turn off.
have the pir power, GND and signal connected directly to the Arduino and the light connected separately to another pin
So the Arduino is powering the PIR from its 5V pin ?
You have set the PIR to output a momentary signal to the Arduino, lets assume you have set this to a 1 second pulse when the PIR detects your foot movement ?
you move your foot the LED light will turn ON, you move your foot again the light will go OFF ?
if you move your foot to turn on the LED light and then not move your foot again, you want the LED light to go OFF after 15 minutes ?
yep powered from the 5v pin.
i think the HIGH pulse it sends is a couple seconds long but yeah essentially.
and yep those are the things I'm looking to do with it.
