GL3522-22 Datasheet

© 2014 Genesys Logic, Inc. - All rights reserved.

Page 17

GLI Confidential

unicast rather than broadcast. Packet only travels the direct path in-between host and the target device.

SuperSpeed traffic will not reach an unrelated device. When enabled for U1/U2 entry, and there is no

pending traffic within comparable exit latency, GL3522-22 will initiate U1/U2 entry to save the power. On

the other hand, the link partner of GL3522-22 may also initiate U1/U2 entry. In this case, GL3522-22 will

accept or reject low power state entry according to its internal condition.

4.2.11 Router/Aggregator Engine

Router/Aggregator Engine implements the control logic defined in Chapter10 of USB3.0 specification.

Router/Aggregator Engine uses smart method for route packet to device or aggregate packet to host.

4.2.12 REPEATER

Repeater logic implements the control logic defined in Section 11.4 and Section 11.7 of USB specification

revision 2.0. REPEATER controls the traffic flow when upstream port and downstream port are signaling in

the same speed. In addition, REPEATER will generate internal resume signal whenever a wakeup event is

issued under the situation that hub is globally suspended.

4.2.13 TT

TT (Transaction Translator) implements the control logic defined in Section 11.14 ~ 11.22 of USB

specification revision 2.0. TT basically handles the unbalanced traffic speed between the USPORT (operating

in HS) and DSPORTS (operating in FS/LS) of hub. GL3522-22 adopts multiple TT architecture to provide

the most performance effective solution. Multiple TT provides control logics for each downstream port

respectively.

4.2.13.1 Connected to 1.1 Host/Hub

If an USB 2.0 hub is connected to the downstream port of an USB 1.1 host/hub, it will operate in USB 1.1

mode. For an USB 1.1 hub, both upstream direction traffic and downstream direction traffic are passing

through REPEATER. That is, the REPEATER/TT routing logic will route the traffic channel to the

REPEATER.

USB 1.1 Host/Hub

REPEATER

TT

DSPORT operating

in FS/LS signaling

USPORToperating

in FS signaling

Traffic channel

is routed to

REPEATER

TT

Figure 4.2 - Operating in USB 1.1 Schemes