PHYSICAL DEVICE(PHY) SUPPORT OF THE USB2.0 LINK POWER MANAGEMENT ADDENDUM USING A ULPI PHY INTERFACE STANDARD

摘要

protocol ULPI PHY (Universal Serial Bus Transceiver Macrocell Low-Pin Interface Physical Layer Device) by a USB 2.0 by enabling the LPM (Link Power Management) support in the appendix, the reserved PID used in the LPM Extended Transaction through the ULPI bus (Physical Interface Device) may facilitate the transmission of the token. ULPI Tx Cmd (Transmit Command; transmission command) byte in bits [3:00] is Opmode code by the selected four Tx Cmd bits (Tx Cmd of bits [3:00]) in order to verify the ULPI PHY configuration 4''b0 can be re-used with a value of the bit for transmission (indicating the generally No PID transmission), by. ULPI PHY is accordingly based on the value of the bits of the Tx Cmd byte Opmode [3: 0] can be analyzed, when the Opmode is set to 2''b10, that is Opmode is disabled for example, NRZI encoding and transmitting chirp to indicate the bit-stuffing may not transmit the Extended PID. Opmode code is set to 2''b0 showing a normal bit-stuffing, Tx Cmd bits [3: 0] of the transmission (Tx Cmd bits [7: 6] = 2''b01) when set to 4''b0 during, PHY may transmit the Extended PID, after the rest of the extended transaction may be sent to the USB.