NO:
W90P710 Programming Guide
VERSION:
2.1
PAGE:
77
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
10. Enable desired interrupts by programming corresponding bits to
HcInterruptEnable
register and clear interrupt status of these interrupts by programming corresponding bits to
HcInterruptStatus
register
11. Turn on the
Root Hub
port power by issuing
SetGlobalPower
command (writing
0x10000
to
HcRhStatus
register) (Note that W90P710 USB
Root Hub
uses global power
switching mode)
12. Enable W90P710
AIC
(Advanced Interrupt Controller) USB interrupt, which is
IRQ9
13. Connect Hub device driver
6.5.2 USB States
The
Host Controller
has four USB states visible to the
Host Controller Driver
via the Operational
Registers : U
SB
O
PERATIONAL
,
U
SB
R
ESET
,
U
SB
S
USPEND
, and U
SB
R
ESUME
. These USB states are
stored in the
HostControllerFunctionalState
field of the
HcControl
register. The
Host Controller
Driver
can perform some state transitions by modifying the
HostControllerFunctionalState
field of
HcControl
register. The meanings of two bits
HostControllerFunctionalState
field is listed in Table
6-2.
Table 6-2 HostControllerFunctionalState
HostControllerFunctionalState
00b U
SB
R
ESET
01b U
SB
R
ESUME
10b U
SB
O
PERATIONAL
11b U
SB
S
USPEND
You can find possible transitions of USB states in Table 6-3. The followings are some notes about
the USB state transitions :