USB2524 datasheet(39/57 Pages) SMSC

39 / 57 page

USB MultiSwitchTM Hub

Datasheet

SMSC USB2524

Revision 1.91 (08-22-07)

DATASHEET

7.1.4.64

BIT

NUMBER

BIT NAME

DESCRIPTION

7:3

Reserved

Reserved. {Note: Software must never write a ‘1’ to these bits}

INTF_PW_DN

SMBus Interface Power Down

0 = Interface is active

1 = Interface power down after ACK has completed.

{Note: This bit is write once and is only cleared by assertion of the external

RESET_N pin.}

RESET

Reset the SMBus Interface and internal memory back to RESET_N assertion

default settings. {Note: During this reset, this bit is automatically cleared to its

default value of 0.}

0 = Normal Run/Idle State.

1 = Force a reset of the registers to their default state.

If the USB_ATTCH bit is set, then this bit will only reset the non write-protected

registers!

USB_ATTACH

USB Attach (and write protect).

0 = SMBus slave interface is active.

1 = Hub will signal a USB attach event to an upstream device, and the internal

memory (address range 00h-F0h) is “write-protected” to prevent unintentional

data corruption.}

{Note 1: This bit is write once and is only cleared by assertion of the external

RESET_N pin.}

{Note 2: If the SMBus interface is kept active after this bit is set, the

PORT_ASSIGN_12, PORT_ASSIGN_34 PORT_ASSIGN_56,

PORT_ASSIGN_7 and PORT_LOCKOUT registers may be continuously

written to reconfigure port ownership.

USB2524 Scheda tecnica(PDF) 39 Page - SMSC Corporation