#### Test Setup I have wired an DS18B20+ to an RPI Pico and used a 4.7K pullup. The RPI Pico is a stand-in for your board. It uses the `arduino:mbed_rp2040:pico` core rather than the `arduino:mbed_nano:nanorp2040connect` that yours does. However, I'm guessing they're similar enough. #### Test result When I attempt the to use the [matmonk DS18B20 library][1] you mention, I see similar pattern on the RPI Pico's onboard LED. Just the attempt to [construct the object][2] was sufficient to crash. Construction fairly directly [defers to the OneWire][3] library. So, I tried the OneWire library's own [example for reading the DS18B20][4] (with some appropriate modification) and it crashes in the same manner. This lead to searching for and finding issues for the RP2040 on the OneWire github page resulting in (among others) [this find][5]. The answer mentions [OneWireNG][6]. #### The OneWireNG [DallasTemperature example][7] works Or rather, it's the library that works. But, this is the relevant example for it that works for me. I made the following modifications. * All `Serial` usages were replaced with `SerialUSB` because I am using the USB connection for the Serial Monitor (well, a terminal emulator). * I changed the one wire object to use GPIO28 because it was conveniently close to the pins where I was picking up 3.3V and GND: `OneWire ds(28);` It seems plausible **that you could change the `#include <DS18B20.h>` usages** in the two libraries you cited to `#include "OneWireNg_CurrentPlatform.h"` and find that they then work fine. I have not tried this yet. If that's of particluar interest to you I will try it and update. However, this stock example from the OneWireNG library is not crashing and is printing temperatures that rise and fall expected when I manipulate the temperature of the sensor. [1]: https://github.com/matmunk/DS18B20 [2]: https://github.com/matmunk/DS18B20/blob/1.0.0/examples/Single/Single.ino#L6 [3]: https://github.com/matmunk/DS18B20/blob/1.0.0/src/DS18B20.cpp#L3-L6 [4]: https://github.com/PaulStoffregen/OneWire/blob/v2.3.7/examples/DS18x20_Temperature/DS18x20_Temperature.ino [5]: https://github.com/PaulStoffregen/OneWire/issues/105 [6]: https://github.com/pstolarz/OneWireNg/ [7]: https://github.com/pstolarz/OneWireNg/blob/0.12.2/examples/arduino/DallasTemperature/DallasTemperature.ino