QTR difference between new and old sensors

Hi just wondering what the actually difference between the old qtr sensors is apart from the number of leds? how does the arduino handle 8 analog outputs when it only has 6 inputs? also whats the difference between the analog and digital new qtr sensors?

thanks tim

Hello, Tim.

This blog post by Jan talks about the new features of those QTR sensors and the differences between them. Strategies for using QTR sensors with more sensors than you might have pins might include not using all of the senors, using a QTRRC version so you can take advantage of the higher number of digital pins, or using some type of multiplexing.

By the way, the Arduino Leonardo and our A-Star programmable controllers both have 8 analog input pins available.


it doesn’t say that the old and new qtr sensors are not compatible and a bought two of them!

Please feel free to share your experience with those new QTR sensors once you get them running, and let us know if you need further help.


is the new qtr sensor compatible with the old zumo?

The sensors on the board should be fine, but the pinouts of those two boards are very different, so you would need to figure out how you would mount the new board and wire it to the Zumo shield.