Light Sensor Timer

Projects Programming
1

Hi Everyone! I need a little help in writing some code for my project.

The idea is that I measure the total time that the light meter reads above (or is equal to) 1500 lux.

Context: a project for a wearable device that tracks the time you spend outdoors every day (above or equal to 1500 lux brightness detects that you must be outdoors)

So far I have approached this by saying that...

when the lux value is greater than or equal to 1500lux,
add 10 seconds (10,000ms) to a container "a" for ( total time outdoors)

the code does this check every 10 seconds

But there is a problem with the code and I don't know what's wrong,
specifically on the line I have coloured in red, it says "expected initialiser before "+" token" :

Code:
#include <BH1750.h> //Sensor Library
#include <Wire.h> //12C Library
BH1750 lightMeter;

void setup() {
// put your setup code here, to run once:
Serial.begin(9600);
Wire.begin();
lightMeter.begin();

uint16_t a =0; //a=total time outdoors in ms
int x =10000;

}

void loop() {
// put your main code here, to run repeatedly:

uint16_t lux = lightMeter.readLightLevel();

if (lightMeter.readLightLevel()>=1500){
uint16_t a+ int x;
//+10 seconds to total time
}

delay (10,000)//checks if you are outside every 10 seconds, if so it assumes that for those 10 seconds since the last check you have been outdoors and adds this on to total outdoor time

2

(deleted)

3

Give this a try:

#include <BH1750.h> //Sensor Library
#include <Wire.h> //12C Library
BH1750 lightMeter;

uint32_t totalTime = 0; // total time outdoors in ms
int tenSeconds = 10000;

void setup()
{
  // put your setup code here, to run once:
  Serial.begin(9600);
  Wire.begin();
  lightMeter.begin();
}
void loop()
{
  // put your main code here, to run repeatedly:
  uint16_t lux = lightMeter.readLightLevel();
  if(lux >= 1500)
  {
    totalTime += tenSeconds;   //+10 seconds to total time
  }
  Serial.println(totalTime);  
  delay(10);
}
4

Hey Guys!

I am attempting to get a BH1750 light sensor to time the duration that the surrounding light is above 1500 lux...

Upon pressing a push button:

If greater than 1500 Lux for less than 60 mins a red light clashes

-if the surrounding light intensity has been greater than 1500 lux for 60-90 mins a yellow light flashes

If greater than 1500lux for more than 90mins in total a green light flashes

I Cannot seem to sort out a problem with the code I have written (well numerous actually they keep coming)

I am new to arduino and any help would be hugely appreciated (see attached images of code)

1515372684655-593938164.jpg
1515372684655-593938164.jpg2560×1536 551 KB

5

Threads merged.

6

It would be helpful if you'd copy/paste ALL of the code in code tags. As it is only setup() is visible.

code tags.PNG

code tags.PNG