Samsung T1000LM026 用户手册
Spinpoint M8U-Internal Product Manual REV 3.4
70
INSTALLATION
Figure 6-33 Information Returned by a GetStatus() Request to a Device
The Self Powered field indicates whether the device is currently self-powered. If D0 is reset to zero, the
device is bus-powered. If D0 is set to one, the device is self-powered. The Self Powered field may not be
changed by the SetFeature() or ClearFeature() requests.
The Remote Wakeup field indicates whether the device is currently enabled to request remote wakeup. The
default mode for devices that support remote wakeup is disabled. If D1 is reset to zero, the ability of the
device to signal remote wakeup is disabled. If D1 is set to one, the ability of the device to signal remote
wakeup is enabled. The Remote Wakeup field can be modified by the SetFeature() and ClearFeature()
requests using the DEVICE_REMOTE_WAKEUP feature selector. This field is reset to zero when the
device is reset.
A GetStatus() request to an interface returns the information shown in Figure 6-33.
device is bus-powered. If D0 is set to one, the device is self-powered. The Self Powered field may not be
changed by the SetFeature() or ClearFeature() requests.
The Remote Wakeup field indicates whether the device is currently enabled to request remote wakeup. The
default mode for devices that support remote wakeup is disabled. If D1 is reset to zero, the ability of the
device to signal remote wakeup is disabled. If D1 is set to one, the ability of the device to signal remote
wakeup is enabled. The Remote Wakeup field can be modified by the SetFeature() and ClearFeature()
requests using the DEVICE_REMOTE_WAKEUP feature selector. This field is reset to zero when the
device is reset.
A GetStatus() request to an interface returns the information shown in Figure 6-33.
Figure 6-34: Information Returned by a GetStatus() Request to an Interface
A GetStatus() request to an endpoint returns the information shown in Figure 6-34.
Figure 6-35: Information Returned by a GetStatus() Request to an Endpoint
The Halt feature is required to be implemented for all interrupt and bulk endpoint types. If the endpoint is
currently halted, then the Halt feature is set to one. Otherwise, the Halt feature is reset to zero. The Halt
feature may optionally be set with the SetFeature(ENDPOINT_HALT) request. When set by the SetFeature()
request, the endpoint exhibits the same stall behavior as if the field had been set by a hardware condition. If
the
currently halted, then the Halt feature is set to one. Otherwise, the Halt feature is reset to zero. The Halt
feature may optionally be set with the SetFeature(ENDPOINT_HALT) request. When set by the SetFeature()
request, the endpoint exhibits the same stall behavior as if the field had been set by a hardware condition. If
the
condition
causing
a
halt
has
been
removed,
clearing
the
Halt
feature
via
a
ClearFeature(ENDPOINT_HALT) request results in the endpoint no longer returning a STALL. For endpoints
using
using
data
toggle,
regardless
of
whether
an
endpoint
has
the
Halt
feature
set,
a
ClearFeature(ENDPOINT_HALT) request always results in the data toggle being reinitialized to DATA0.
The Halt feature is reset to zero after either a SetConfiguration() or SetInterface() request even if the requested
configuration or interface is the same as the current configuration or interface.
It is neither required nor recommended that the Halt feature be implemented for the Default Control Pipe.
However, devices may set the Halt feature of the Default Control Pipe in order to reflect a functional error
condition. If the feature is set to one, the device will return STALL in the Data and Status stages of each
standard request to the pipe except GetStatus(), SetFeature(), and ClearFeature() requests. The device need
not return STALL for class-specific and vendor-specific requests.
The Halt feature is reset to zero after either a SetConfiguration() or SetInterface() request even if the requested
configuration or interface is the same as the current configuration or interface.
It is neither required nor recommended that the Halt feature be implemented for the Default Control Pipe.
However, devices may set the Halt feature of the Default Control Pipe in order to reflect a functional error
condition. If the feature is set to one, the device will return STALL in the Data and Status stages of each
standard request to the pipe except GetStatus(), SetFeature(), and ClearFeature() requests. The device need
not return STALL for class-specific and vendor-specific requests.