Problem when not in debugging mode

[disk91]

It is not clear but it looks like the main MCU does not wakeup from the Sleep-mode when the debug mode is not activated. So the communication is never ending. No explanation, basically the code looks good but is not working. What about the Null callback attachement on wakeupinterrupt ?

[disk91]

After test, I confirm is comes from the Arduino Low Power library never waking up the device after an USB programming. By powering down then up it seems to restart correctly

[manchoz]

Hi @disk91, it seems you are experiencing a very common problem with Low Power/USB/SAMD21. Take a look at the forum for possible solutions (https://forum.arduino.cc/index.php?board=113.0). A short explanation for what it's probably happening on your MKRFOX is at https://forum.arduino.cc/index.php?topic=478950.msg3273016#msg3273016.

A complete working sketch with no debug mode, low power mode and debug on Serial2 is at https://github.com/manchoz/iottrack_sigfox/blob/master/Arduino/WeatherMonitorDHT/WeatherMonitorDHT.ino.

[vallettea]

We are experiencing the same issue.