TSB41AB3IPFPEP datasheet(44/55 Pages) TI1

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TSB41AB3EP

IEEE 1394a2000 THREEPORT CABLE TRANSCEIVER/ARBITER

SGLS122C − JULY 2002 − REVISED JUNE 2008

POST OFFICE BOX 655303

• DALLAS, TEXAS 75265

PRINCIPLES OF OPERATION

interface reset and disable (continued)

The sequence of events for resetting the PHY-LLC interface when it is in the differentiated mode of operation

(ISO terminal is low) is as follows:1

Normal operation. Interface is operating normally, with LPS active, SYSCLK active, status and packet

data reception and transmission via the CTL and D lines, and request activity via the LREQ line.

LPS deasserted. The LLC deasserts the LPS signal and, within 1

µs, terminates any request or interface

bus activity, and places its LREQ, CTL, and D outputs into a high-impedance state (the LLC should

terminate any output signal activity such that signals end in a logic 0 state).

Interface reset. After TLPS_RESET time, the PHY determines that LPS is inactive, terminates any

interface bus activity, and places its CTL and D outputs into a high-impedance state (the PHY

terminates any output signal activity such that signals end in a logic 0 state). The PHY-LLC interface

is now in the reset state.

Interface restored. After the minimum TRESTORE time, the LLC may again assert LPS active. (The

minimum TRESTORE interval provides sufficient time for the biasing networks used in Annex J type

isolation barrier circuits to stabilize and reach a quiescent state if the isolation barrier has somehow

become unbalanced.) When LPS is asserted, the interface initializes as described below.

SYSCLK

ISO

(high)

(a)

(c)

(b)

CTL0, CTL1

D0 − D7

LREQ

LPS

(d)

TLPS_RESET

TRESTORE

Figure 24. Interface Reset, ISO High

TSB41AB3IPFPEP Datasheet(PDF) 44 Page - Texas Instruments