Need a USB Device with 2 USB ports.
USBPort1 is allways a device. USBPort2 can be a host or device(OTG).
USBPort1 allways enumerates and behaves as a CD/DVD Rom mass storage device.
USBPort2 must detect 5V and turn to device if so, host otherwise.
When Port2 is a host, it? handles mass storage device with VFAT (with long file name support), anything else is ignored.
When USBPort2? detects 5V- i.e. is connected to a host,? it turns to device and enumerates as a HID (and possibly MSD- TBD).
The project will be further defined when HW is agreed upon.
I am open to both HW and SW proposals.