Circuit Playground Express Temp & Sound Sensors

I purchased a classroom set of Circuit Playground Express boards about 4 months ago for Unit 6. As we approach Lesson 7, I have noticed that the boards are not returning valid temperature and sound sensor data, and they do not respond to changes in environment that should cause changes in output. Is this a known issue, or do I need to contact Adafruit about the possibility of some bad boards? I have tested three boards and they are all returning similar data and none respond to temperature or sound pressure changes.

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I tested my fairly new (within the last 6 months) Circuit Playground Express board. I used the code below to test the temperature using the “data” event and although I did not have a thermometer to verify temperature, the room temperature was probably close or at least within 3-4 degrees at 78 degrees (yes - it was warm:). The main thing is that it fluctuated slightly almost constantly and when I put my finger on the sensor (the thermometer), the temperature rose quickly and displayed in the text box with ID=Temp. I also tested in another room with about the same temperature and fluctuation.

Code I used:
onBoardEvent(tempSensor, “data”, function(event) {
setProperty(“Temp”, “text”, tempSensor.F);

So, if you have tried similar tests and know it is not working I would recommend contacting Adafruit. I did find a forum for educators here:

Good luck!

I think I discovered my error. Temperature sensor is now registering temperature changes, and although the recorded temperature seems 6-7 degrees above actual room temperature, I am getting a response to changes.

With the sound sensor, I went back to Lesson 7-2 and looked closer at the sensors. At first, Sensor 3 did not seem to respond to any input changes, but after further observation, I recognized the high data point does raise from about 520 to 1023 with a sharp noise, such as a clap. It seems very insensitive to other sounds until the sound pressure level gets very loud, then the measurement jumps to near the maximum value. We will have to do some additional testing to actually log levels over time and possibly use a white noise generator maintaining a consistent level to determine whether there are issues with the onboard microphone used as a sensor.

At least I can confirm the boards are responsive now, and students can find a way to work around the accuracy issues as they learn. Thank you for the quick response!

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That’s great! Glad you got it working.