Answered: Ultrasonic report is almost never above mid 30s


I just tried to use 3 Ultrasonic sensors today. I have had them for a while, but this was the day I finally found the time to use them.

The first one reports values ranging from 2 or 3 up to 99. That is good.

The second sensor reports values from 2 or 3 up to about 34. In that range the reports are a good match with what the first sensor reports. Occasionally the second one will report an approriate number greater than mid-30s (that is a close match with what the first sensor supplies); but these are few and far between.

The third sensor behaves like the second one, excpet that it almost never reports anything above a 2 or a 3.

Is this a symptom you recognize? If it is can you recommend a course of action? With the exception of their limited ranges of usefullness, the malfunctioning sensors appear to be working fine.



Thanks for the repaly, you speculated in it that I might have a problem in the code. That possibility seems remote.

Inside of an infinite while loop, I start, read, and stop the sensor using pure EasyC 1.X to write the instructions. After stopping the sensor code I use PrintToScreen to display it, and then Wait for a few hundred mlliseconds before letting the loop execute again.

This was part of a slightly more complicated program (I wanted use all three sensors) but now everything but this little section is commented out.

So I don’t think the code is the problem. The code works well with the one “good” sensor. I think the problem lies in the other two sensors.

About adjusting the Sensors’ Tx/Rx modules. How are they mounted? Are the mounting materials sensitive enough to heat to be damaged by sitting in a car? Do you bend them or loosen them with a tiny screw driver? Any advice before I crack one open?