Hello All, I am trying to know in which state a RGB LED is. In order to accomplish that, I use a photoresistor connected to an analog pin ( arduino Pin) The led can be in three state : RED / Orange / Green I bought an built-in photoresistor system : here . But, even if, the photoresistor is just …

Each color has his own luminosity. As example, I need to increase sensitivity in order to catch the green light. So, In my mind. the frist step is to calibrate manually my arduino but I cannot do that because I get always the same range of value.

That module has a digital output. It is only intended to show light or no light, as the description very clearly says. You need a different module if you want an analog output. Steve

I am very surprised ! I checked in web and found some articles like that : https://www.instructables.com/id/Color-Detection-Using-RGB-LED/ As you can see, I am in the same situation and I am using same components.

Ok I checked and you are right . Thanks for your help

Don't waste your time with Instructables, most of the electronics or Arduino related ones are posted by people who have no idea what they are doing.

The instructable actually seems ok (I skimmed it). But the point of the instructable is not to detect what color of light a LED gives off, but to detect what color an object is by reflecting colored light off of it. When you do this, you already know what color the LED gives off, because the MCU te…

Bizarre Instructable. I wonder what the author had in mind with this completely idiotic circuit:

Galfisk got what I was inferring. You need different sensors with filters. Otherwise you don’t know if the sensor is reading a color or level.

My main concerned is that my LDR module has only one digital output. So as you said, I can only have binary data. I found an LDR with analog output I will try it soon. I made a hack of my alarm keyfob in order to be able to arm or disable it remotely. I need to check the colour led to confirm th…

Photoresistor and strange input on analog pin

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wolframore January 29, 2019, 10:51pm 2

question - how is that photoresistor suppose to know what color it is as apposed to there's a light on???

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Photoresistor and strange input on analog pin

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