H8S USB Project by Ly @ Vu Enterprises
This web site has loads of details about a serial port emulator that was designed by Ly. This level of detail is really unusual, and an outstanding resource for anyone implementing USB device level products using the H8S/2215 or H8S/2218 or 2212. Ly includes a write-up, schematic, PowerPoint slides and a data flow model.
Very nice work documenting the USB interface:


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