USBSerial USB_EP_SIZE = 64
USBSerial connect
hello there

USBSerial waiting...

USBSerial resumed
goodbye

USBSerial waiting...

USBSerial waiting...

USBSerial waiting...
printUSB():  not ok;  USBSerial.availableForWrite() returned 64
USBSerial.write() returned 0 for USBSerial.write() length 22