USS-820D View Datasheet(PDF) - Agere -> LSI Corporation

Part Name

Description

Manufacturer

USS-820D

USB Device Controller

Agere -> LSI Corporation 

USS-820D

USB Device Controller

Data Sheet, Rev. 4

June 2001

Register Interface (continued)

Table 16. Start of Frame Low Register (SOFL)—Address: 0EH; Default: 0000 0000B

This register contains the lower 8 bits of the 11-bit time stamp received from the host.

Bit 7

TS7

Bit 6

TS6

Bit 5

TS5

Bit 4

Bit 3

TS4

TS3

R/W (S*)

Bit 2

TS2

Bit 1

TS1

Bit 0

TS0

Bit

Symbol

Function/Description

7:0

TS[7:0] Time Stamp Received from Host. This time stamp is valid only if the SOFACK bit in

the SOFH register is set. TS[7:0] are the lower 8 bits of the 11-bit frame number

issued with an SOF token. The time stamp remains at its previous value if an artificial

SOF is generated, and it is up to firmware to update it. These bits are set and cleared

by hardware.

* S = shared bit. See Special Firmware Action for Shared Register Bits section.

Table 17. Endpoint Index Register (EPINDEX)—Address: 0AH; Default: 0000 0000B

This register identifies the endpoint pair. The register’s contents select the transmit and receive FIFO pair and

serve as an index to endpoint-specific special function registers (SFRs).

Bit 7

Bit 6

Bit 5

—

—

Bit 4

Bit 3

Bit 2

EPINX2

Bit 1

EPINX1

R/W

Bit 0

EPINX0

Bit

Symbol

Function/Description

7:3

—

Reserved. Write 0s to these bits. Reads always return 0s.

2:0

EPINX[2:0] Endpoint Index.

EPINDEX*

0000 0000

0000 0001

0000 0010

0000 0011

0000 0100

0000 0101

0000 0110

0000 0111

Function Endpoint

Function Endpoint 0

Function Endpoint 1

Function Endpoint 2

Function Endpoint 3

Function Endpoint 4

Function Endpoint 5

Function Endpoint 6

Function Endpoint 7

The EPINDEX register must not be changed during a sequence of RXDAT reads of a

particular data set. See the Receive FIFO section for more details.

* The EPINDEX register identifies the endpoint pair and selects the associated transmit and receive FIFO pair. The value in this register plus

SFR addresses select the associated band of endpoint-indexed SFRs (TXDAT, TXCON, TXFLG, TXCNTH/L, RXDAT, RXCON, RXFLG,

RXCNTH/L, EPCON, TXSTAT, and RXSTAT).

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Agere Systems Inc.

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