QTR-RC to detect multiple colored lines

I would like to know if it’s possible to use the QTR-RC to follow a red line and a green line on a white background.
Differentiating between red and green is hoped for but only optional. I would be happy to just be able to follow either a red or a green line regardless of which one is which?

Would the 8A be more suited to color recognition than the RC ?

Question 2 : Is it possible to establish another type of communication between the Arduino and the reflectance sensor (I²C for example) to ask for a value and to get a response from the sensor?
In other words, is it mandatory to use a digital/analog pin for each sensor or is there another way?
Thank you


Your first question was already answered here; both the QTR-8A and QTR-8RC versions use the same senor, so the answer is the same.

No, these sensor arrays do not support I2C; each sensor will need its own pin.


Thank you very much !

Does the Zumo reflectance sensor support I²C ?

I hope you’ll be quicker to answer since I’m currently putting my order on hold and I don’t know which to choose between the QTR-RC and the Zumo sensor. If the Zumo does support I²C I might consider buying it instead of the QTR-RC.

Thank’s again


No, it does not. You can see this clearly from the product page, which fully documents the sensor (it should be obvious from the schematic alone that there is no higher-level interface available).

- Ben

Hi Ben, Thank you very much for clearing that up.

I just wanted to make sure because in here :

You can see an SCL and SDA pin colored in indigo. So I thought hopefully we could use them to ask for sensor values.

Anyways thanks again !