NO:
W90P710 Programming Guide
VERSION:
2.1
PAGE:
78
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed,
distributed or reproduced without permission from Winbond.
Table No.: 1200-0003-07-A
•
After hardware reset, the
Host Controller
will enter U
SB
R
ESET
state.
•
In any state, programming one to the
HostControllerReset
bit of
HcCommandStatus
register, will force the
Host Controller
to perform software reset. After software reset, the
HC will enter U
SB
S
USPEND
state, instead of U
SB
R
ESET
state.
•
If HC is in U
SB
S
USPEND
state, it will enter U
SB
R
ESUME
state either by
HCD
writing 0x1 to
HostControllerFunctionalState
or by remote wakeup. To enable HC resume by remote
wakeup,
HCD
must enable the
DeviceRemoteWakeupEnable
bit of
HcRhStatus
register.
HCD
can enable
ResumeDetected
interrupt to sense the case.
Table 6-3 USB state transition table
From state
Convert to state
Conditions
U
SB
R
ESET
Hardware Reset
U
SB
R
ESET
U
SB
O
PERATIONAL
Writing 0x2 to
HostControllerFunctionalState
U
SB
S
USPEND
1. Writing
0x3
to
HostControllerFunctionalState
2.
Issue a Software Reset command
U
SB
O
PERATIONAL
U
SB
S
USPEND
1.
Writing 0x3 to
HostControllerFunctionalState
2.
Issue a Software Reset command
U
SB
R
ESET
Writing 0 to
HostControllerFunctionalState
U
SB
S
USPEND
U
SB
R
ESUME
1. Writing
0x3
to
HostControllerFunctionalState
2.
Resumed by device
U
SB
O
PERATIONAL
Writing 0x2 to
HostControllerFunctionalState
U
SB
R
ESET
Writing 0 to
HostControllerFunctionalState
U
SB
R
ESUME
U
SB
O
PERATIONAL
Writing 0x2 to
HostControllerFunctionalState
U
SB
R
ESET
Writing 0 to
HostControllerFunctionalState
6.5.3 Add/Remove Endpoint Descriptors
In
Host Controller
architecture, a device endpoint is described by an
ED
(
Endpoint Descriptor
).
Host Controller
has Control, Bulk, Interrupt, and Isochronous
Endpoint Descriptor
lists. The Control
and Bulk
ED
lists are referred to by
HcControlHeadED
register and
HcBulkHeadED
register
respectively. The Interrupt endpoints are organized into 32 Interrupt
ED
lists with each list pointed by