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Cirrus Logic EP93xx User Manual

Page 461

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DS785UM1

11-21

Copyright 2007 Cirrus Logic

Universal Serial Bus Host Controller

EP93xx User’s Guide

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Default:

0x0000_0000

Definition:

Physical address of the current isochronous or interrupt endpoint descriptor.

Bit Description:

RSVD:

Reserved. Unknown During Read.

AD:

PeriodCurrentED. This is used by HC to point to the head
of one of the Periodic lists which will be processed in the
current Frame. The content of this register is updated by
HC after a periodic ED has been processed. HCD may
read the content in determining which ED is currently
being processed at the time of reading.

HcControlHeadED

Address:

0x8002_0020

Default:

0x0000_0000

Definition:

Physical address of the first endpoint descriptor of the control list.

Bit Description:

RSVD:

Reserved. Unknown During Read.

AD:

ControlHeadED. HC traverses the Control list starting with
the HcControlHeadED pointer. The content is loaded from
HCCA during the initialization of HC.

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AD

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AD

RSVD