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PD720231
4. USB Descriptor Information
R19UH0094EJ0100 Rev 1.00
Page 11 of 30
Mar 1, 2013
4.2
BOS (Binary device Object Store) Descriptor
The BOS descriptor defines a root descriptor that is similar to the configuration descriptor, and is the base
descriptor for accessing a family of related descriptors.
Offset Field Size
Value
Description
0
bLength
1
05h
Size of descriptor
1
bDescriptorType
1
0Fh
BOS descriptor type
2
wTotalLength
2
0016h
Length of this descriptor and all of its sub descriptors
4
bNumDeviceCaps
1
02h
The number of separate device capability descriptors
in the BOS.
4.2.1
USB2.0 Extension Descriptor (High-/Full-speed only)
A Super-speed device shall include the USB2.0 Extension descriptor and shall support LPM when
operating in USB2.0 High-speed mode.
Offset Field Size
Value
Description
0
bLength
1
07h
Size of descriptor
1
bDescriptorType
1
10h
Device capability descriptor type
2
bDevCapabilityType
1
02h
Capability type: USB2.0 Extension
3 bmAttributes
4 00000002h
Link
Power Management protocol supported
4.2.2
Super Speed USB Device Capability Descriptor (High-/Full-speed only)
Device Capability descriptors describe individual technology-specific or generic device-level capability.
Offset Field Size
Value
Description
0
bLength
1
0Ah
Size of descriptor
1
bDescriptorType
1
10h
Device capability descriptor type
2
bDevCapabilityType
1
03h
Capability type: Super Speed USB Device Capability
3
bmAttributes
1
00h
Latency Tolerance Messages not supported
4 wSpeedsSupported
2 000Eh Super/High/Full-speed supported
6 bFuntionalitySupport 1 03h
Full
functionality
7
bU1DevExitLat
1
0Ah
U1 Device Exit Latency
8
bU2DevExitLat
2
03E8h
U2 Device Exit Latency
