udoo bolt. ATmega32u4 disapears from USB list.

After uploading a sketch unable connect anymore.

Distro: Archlinux. Kernel: 5.3.11-arch1-1

Kernel messages:
[ 2509.512704] cdc_acm 3-2:1.0: ttyACM0: USB ACM device
[ 2517.124186] usb 3-2: USB disconnect, device number 15
[ 2517.382934] usb 3-2: new full-speed USB device number 16 using xhci_hcd
[ 2517.722888] usb 3-2: device descriptor read/64, error -71
[ 2518.008660] usb 3-2: device descriptor read/all, error -71
[ 2518.129608] usb 3-2: new full-speed USB device number 17 using xhci_hcd
[ 2518.279675] usb 3-2: device descriptor read/64, error -71
[ 2518.536302] usb 3-2: device descriptor read/64, error -71
[ 2518.643032] usb usb3-port2: attempt power cycle
[ 2519.286262] usb 3-2: new full-speed USB device number 18 using xhci_hcd
[ 2519.443129] usb 3-2: device descriptor read/64, error -71
[ 2519.753289] usb 3-2: device descriptor read/all, error -71
[ 2519.876277] usb 3-2: new full-speed USB device number 19 using xhci_hcd
[ 2520.005899] usb 3-2: device descriptor read/64, error -71
[ 2520.315429] usb 3-2: device descriptor read/all, error -71
[ 2520.315516] usb usb3-port2: unable to enumerate USB device

Tried kernel parameter usbcore.old_scheme_first=1. After microcontroller reset button built in led fades in-on and after that i got same kernel message list.

 

Update: Uploaded sketch seems working.

 

Tried reset button press twice quickly. No change.
-
usb 3-2: Product: Arduino Leonardo
usb 3-2: Manufacturer: Arduino LLC
cdc_acm 3-2:1.0: ttyACM1: USB ACM device
usb 3-2: USB disconnect, device number 22
usb usb3-port2: unable to enumerate USB device
-

 

Yes, Estonian singing revolution sentence was "once we win anyway", multiple times button press and trying worked
Case closed.

 

There are some known issues with the Arduino Leonardo: https://www.udoo.org/docs-bolt/Ardu...4)/Getting_Started_with_Arduino_Leonardo.html