Hi!
I wrote a C++ class on debian stretch on a raspberry that communicates with an Adafruit ItsyBitsy M4 or a Feather Express M4 using libusb. Well - native USB is a little bit more tricky and I would not molest anyone when I would be unsure that there is something really strange going on:
- When compiling my code for the Feather with Arduino IDE 1.8.5, all works fine. The Raspi sends something, and the Feather responds accordingly, and all is fine.
- That works also when I use the terminal of the Arduino IDE. I send something, and the feather reacts. I use "Serial.write()" to send data via USB and "Serial.read()" on the Feather.
When uploading the code from Arduino IDE 1.8.7
- all works fine with the IDE terminal
- when connecting with the Raspberry and my C++ program, I can send data which are recognized by the Feather (at least I think so - i fire up the red LED on pin 13 for certain characters, and turn it off with others) but
- i cannot send anything ... both with the ItsyBitsy M4 and the Feather Express M4!!!
I have not tried it yet with another native USB board such as the Teensy, but this is really strange - does someone have an idea???
yours
wolfi
PS: cross posted this also in the Adafruit forum