Hitachi HD64465 User Manual page 281

USB OPERATIONAL
When in the U O
SB PERATIONAL
Tokens. The U O
SB PERATIONAL
may be exited to the U
When transitioning from U
responsible for terminating the USB reset or resume signaling as defined in the USB Specification
prior to sending a token.
A transition to the U
SB
Controller. Simultaneously with the Host Controller state transition to U
FrameRemaining field of HcFmRemaining is loaded with the value of the FrameInterval field in
HcFmInterval. There is no SOF Token sent at this initial load of the FrameRemaining field. The
first SOF Token sent after entering the U
boundary when FrameRemaining transitions from 0 to FrameInterval. The FrameNumber field
of HcFmNumber is incremented on a state transition to U
USB RESET
When in the U R
SB ESET
Controller list processing and SOF Token generation are disabled while in U
the FrameNumber field of HcFmNumber does not increment while the Host Controller is in the
U R state. The U
SB ESET
Controller defaults to the U
is responsible for satisfying USB Reset signaling timing defined by the USB Specification.
USB SUSPEND
The U S state defines the USB Suspend state. The Host Controller list processing and
SB USPEND
SOF Token generation are disabled. However, the Host Controller remote wakeup logic must
monitor USB wakeup activity. The FrameNumber field of HcFmNumber does not increment
while the Host Controller is in the U
U S is entered following a software reset or from the U
SB USPEND
command from the Host Controller Driver. While in U
transition to the U R
SB
with the Host Controller Driver initiating a transition to the U
occurs, the HCD-initiated transition to U
wait 5 ms after transitioning to U
Likewise, the Root Hub must wait 5 ms after the Host Controller enters U
generating a local wakeup event and forcing a transition to U
reset, the Host Controller Driver may cause a transition to U
occurs no more than 1 ms from the transition into U
possible that devices on the bus will go into Suspend.
Rev. 3.0, 03/01, page 262 of 390
state, the Host Controller may process lists and will generate SOF
state may be entered from the U
R or U S
SB ESET SB USPEND
R or U
SB ESET SB
O state affects the frame management registers of the Host
PERATIONAL
SB
state, the Host Controller forces reset signaling on the bus. The Host
R state can be entered from any state at any time. The Host
SB ESET
R state following a hardware reset. The Host Controller Driver
SB ESET
S
SB USPEND
state due to a remote wakeup condition. This transition may conflict
ESUME
SB
S
SB USPEND
states.
R to U O
ESUME SB PERATIONAL
O state is sent following next frame
PERATIONAL
O
SB PERATIONAL
state.
S
SB USPEND
R
SB
R has priority. The Host Controller Driver must
ESET
before transitioning to the U
R
SB
O
SB
S . If the 1-ms period is violated, it is
SB USPEND
R or U R
SB ESUME SB ESET
, the Host Controller is
O
SB PERATIONAL
.
R
SB ESET
O state on
SB PERATIONAL
, the Host Controller may force a
state. If this situation
ESET
R state.
SB ESUME
S
SB USPEND
. Following a software
ESUME
if the transition
PERATIONAL
states. It
, the
. In addition,
before