QTR 8RC resistor

So I dont really know how to solder. I paid somebody to do it for me. He soldered all the male header pins that came with the sensor. However, he also soldered the 100 Ohm resistor that comes with it.

In the datasheet, it says that you should solder the 100 Ohm resistor only if you plan to break it into 2 submoduls. I do not intend this. I want readings from all 8 sensors.

Should I desolder this resistor? Will it affect my readings? The board hasn’t been cut.
I read everything in point 6 of this PDF : https://www.pololu.com/docs/pdf/0J12/QTR-8x.pdf

Another question that has to do with the programming of the QTR 8RC:

#define MIDDLE_SENSOR 4,5

when using the arduino UNO, does it count sensors from 0-7? or from 1-8?
If it counts from 0-7, then the “middle sensor” would be between 3 and 4
If it counts from 1-8, then the “middle sensor” would be between 4 and 5.

So if I #define MIDDLE_SENSOR 4,5 does arduino know that I mean the space between 4 and 5?


Leaving that resistor on won’t damage anything, but it will affect the brightness of the IR LEDs and in turn the readings. If you do not plan on breaking off the two sensors, you could just cut the resistor off.

The code you posted does not look like it is from our library or examples. You should probably ask the person who wrote the code for help using it. Alternatively, you might consider using our library and looking at our examples. You can find a user’s guide for our Arduino library for the QTR sensors under the “Resources” tab of the QTR sensor’s product page.