Selecting USB Host / Device on boot

[PinkPandaKatie]

I would like to be able to switch between USB host mode and device mode on startup, but I have to either select usb=tinyusb or usb=tinyusb_host as a parameter. I thought maybe I could select host mode by not doing Serial.begin and instead using USBHost.begin (where USBHost is an instance of Adafruit_USBH_Host), but regardless, it still comes up as a CDC ACM device.

If I select usb=tinyusb_host, then it never shows up as a device.

Any ideas on how to select this at runtime without hacking the SDK?

[earlephilhower]

I don't think what you want can be done in a straightforward manner. Changing between host and device mode is done through a -DUSE_TINYUSB_HOST which is going to modify the compiled TinyUSB sources. You can't build them twice with different defines, the structs/functions will all be redefined (and differ).

It may be possible to do some very hacky bits by making a duplicate of the Adafruit_TinyUSB library and place everything there in another namespace, but I don't think it would be very pleasant to work with (if even really possible...)

For the definitive answer, I would suggest checking the upstream library repo and posting something there...