Is there any way to wake a T4 or 4.1 when there is incoming USB traffic? The sleep library documentation states that usbSerial does not wake the Teensy.
Looking further into the Snooze libary, I ran into the SnoozeUSBSerial example.
Apparently you can use USB Serial output but it's not a wake-up source. So the USB interface is actually active in Sleep mode.
Forum member @duff might be able to tell more...