[SOLVED] Pro Mini 3.3v with DS18B20 sensor getting (-)127 Celsius!
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I hooked up DS18B20 to Pro Mini 3.3v using Vcc (3.3v). But the temp reading is constant at -127 degree Celsius. Below is my wiring with 4k7 Ohm resistor across data and vcc. I did some googling and some say -127 C reading means incorrect wiring. Is my wiring wrong?
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@gogopotato the - 127 can either mean that your sensor is not working or is read in the wrong way. Which sketch are you using? (the connections look ok)
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@AWI I'm using the example provided in https://www.mysensors.org/build/temp
numSensors = sensors.getDeviceCount();
The above statement is returning zero. So perhaps I have a faulty/dead sensor? I should have tested the sensor before soldering it in...
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@gogopotato The DS18B20 is a pretty solid device, but there is a chance that it's broken. Re-check your wiring and measure the resistor before breaking anything.
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@AWI I will try that. Thanks!
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@AWI Turns out, I was using 47k resistor instead of 4.7k resistor. Now it's working with no issue