Can I use USB in a bootloader on the nRF52840?

[Roger Clark]

Before I try something which is technically impossible....

Does anyone know if the USB functions on the nRF52840 would work in the bootloader, or only in the application?

[Roger Clark]

@RK

Thanks.

I would need something on the nRF52840 side that didnt need a special driver on the PC / Mac / Linux side.

So CDC was a possibility as all those OS's have a built in CDC driver, (though its a bit tricky on Windows 7 and 8 to convince Windows to use its built in driver).

Another possibility could be HID, but I'd need bi-directional comms, and although I think thats possible, I have only used a keyboard / Mouse / Joystick HID device before which was input into the PC

So I'd need to do some more research around bidirection comms.

Mass storage may be another option, but I have a feeling that would be even more complicated as I'd need a fake FS on the nRF52840 side