+========-============================-===================+ | Mode | Description | Type | |--------+----------------------------+-------------------| | 000b | Combined header and data | Optional | | 001b | Vendor-specific | Vendor-specific | | 010b | Data | Optional | | 011b | Descriptor | Optional | | 100b | Reserved | Reserved | | 101b | Reserved | Reserved | | 110b | Reserved | Reserved | | 111b | Reserved | Reserved | +=========================================================+