QTR 8A vs QTR 8RC

Hi, which sensor takes the least time to read its value between QTR 8A and QTR 8RC? How many times can you tell the difference?

Hello.

It will generally depend on your microcontroller, but in most cases, the RC version is going to be quicker. Since the RC version is a digital pulse, you can take all of the readings in parallel, whereas if you’re using a microcontroller with only one ADC, your analog readings would need to be taken sequentially.

Since the RC sensors work by timing the length of a digital pulse, the actual time it takes to make the reading depends on whether it is taking a reading of a light or dark surface. For example, a pulse taken from a white surface might be in the range of 40μs, whereas a reading of a black surface can reach the configured timeout value (which is 2500μs by default in our QTR library).

Brandon