I am developing a custom board based on the IMXRT1052. Included on the board is an ADuM4160 USB isolator for galvanic isolation. This isolator part has a maximum operating speed of 12 Mbps (USB 2 full-speed).
When trying to connect to the flashloader (after loading via MCUBoot) through the isolator, as the host tries to negotiate down to USB full speed, it doesn't seem that flasloader handles the chirps and remains in USB hi-speed mode, causing a failure to enumerate... is there some way to force MCUBoot/Flashloader to use USB full speed?
This is easily tested by putting an external USB isolator that uses the same ADuM chip between the IMXRT EVK and the USB host. Something like this: USB isolator