Datasheet

Hi-Speed USB Host, Device or OTG PHY with ULPI Low Pin Interface

Datasheet

Revision 1.1 (01-24-13) 30 SMSC USB3300

DATASHEET

6.1.4.12 Debug Register: Address = 15h (read only)

6.1.4.13 Scratch Register: Address = 16-18h (read), 16h (write), 17h (set), 18h (clear)

6.1.4.14 Carkit Register Access

The Carkit registers are reserved for SMSC testing and should not be written to or read by the Link.

6.1.4.15 Extended Register Access

The extended registers are reserved for SMSC testing and should not be written to or read by the Link.

6.1.4.16 Vendor Register Access

The vendor specific registers are reserved for SMSC testing and should not be written to or read by

the Link. The vendor specific registers include the range from 30h to 3Fh.

6.1.5 ULPI Register Access

A command from the Link begins a ULPI transfer from the Link to the USB3300. Anytime the Link

wants to write or read a ULPI register, the Link will need to wait until DIR is low, and then send a

Transmit Command Byte (TXD CMD) to the PHY. The TXD CMD byte informs the PHY of the type of

data being sent. The TXD CMD is followed by the a data transfer to or from the PHY. Table 6.4, "ULPI

TXD CMD Byte Encoding" gives the TXD command byte (TXD CMD) encoding for the USB3300. The

upper two bits of the TX CMD instruct the PHY as to what type of packet the Link is transmitting.

FIELD NAME BIT DEFAULT DESCRIPTION

Linestate0 0 0b Contains the current value of Linestate[0].

Linestate1 1 0b Contains the current value of Linestate[1].

Reserved 7:2 000000b Driven low.

FIELD NAME BIT DEFAULT DESCRIPTION

Scratch 7:0 00h Empty register byte for testing purposes. Software can read,

write, set, and clear this register and the PHY functionality will

not be affected.

Table 6.4 ULPI TXD CMD Byte Encoding

COMMAND NAME

CMD

BITS[7:6] CMD BITS[5:0] COMMAND DESCRIPTION

Idle 00b 000000b ULPI Idle

Transmit 01b 000000b USB Transmit Packet with No Packet Identifier

(NOPID)

00XXXXb USB Transmit Packet Identifier (PID) where DATA[3:0]

is equal to the 4-bit PID. P

where P

is the

MSB.