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  • @Oscar, I read something about the heart beat the AT42QT1010 can send out... and that could have messed with you... The data sheet says that the heart beat is not strong enough to make an LED lite up to be noticed by naked eye and and it can be filtered out w/ (capacitive) load... Since I have seen different board population and the option of being able to have the LED connected or not, this could also have contributed. For what ever reason this heart beat could have confused the readings and explains why the analog read always almost HIGH (3.22 vs 3.33). In addition, I said that you do not need a pull-down (on the input side) because the schema showed a pull-down on the out-put but the board does not have one, the heart beat could create this confusion. See https://cdn-shop.adafruit.com/datasheets­/AT42QT1010.pdfhttps://cdn-shop.adafruit­.com/datasheets/AT42QT1010.pdf pages 10 and 11 (pages attached)... - Why though without change of circuitry and only clearing software on the MDBT42Q fixed the issue... not much other than on the init before somehow the wire / pin got loaded with initial high the capacities and something else held them high enough for the analog to read something where as the regular input did not fire... the debounce did not help either here: it could have consider the heart beat as bouncing...

    No matter what, you got it going... and having a pinMode(pinRef, "input_pulldown"; - when LED is not enabled - is a good thing... (What color is the built in LED and what is its forward voltage?)


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    • AT42QT1010_output_heartbeat.png
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