Device Qualifier Descriptor (High-/Full-Speed Only); Other_Speed_Configuration Descriptor (High-/Full-Speed Only) - Renesas mPD720231 User Manual

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PD720231

4.7 Device Qualifier Descriptor (High-/Full-speed only)

A device qualifier descriptor describes general information about a high-speed capable device that would
change if the device were operating at the other speed.
full-speed, the device qualifier returns information about how it would operate at high-speed and vice-versa.
Offset Field
0 bLength
1 bDescriptorType
2 bcdUSB
4 bDeviceClass
5 bDeviceSubClass
6 bDeviceProtocol
7 bMaxPacketSize0
8 bNumConfigurations
9 Reserved
4.8

Other_Speed_Configuration Descriptor (High-/Full-speed only)

An other_speed_configuration descriptor describes a configuration of a high-speed capable device if it were
operating at its other possible speed.
configuration descriptor. When the host requests the other_speed_configuration descriptor, all related
interface and endpoint descriptors are returned.
Offset Field
0 bLength
1 bDescriptorType
2 wTotalLength
4 bNumInterfaces
5 bConfigurationValue
6 iConfiguration
7 bmAttributes
8 bMaxPower
R19UH0094EJ0100 Rev 1.00
Mar 1, 2013
Size Value
1 0Ah Size of descriptor
1 06h Device qualifier descriptor type
2 0210h USB specification version number (BCD)
1 00h Class Code
1 00h SubClass Code
1 00h Protocol Code
1 40h Maximum packet size for this speed (64 bytes)
1 01h Number of this speed configuration
1 00h Reserved for future use.
The structure of the other_speed_configuration is identical to a
Size Value
1 09h Size of descriptor
1 07h Other_speed_configuration descriptor type
2 0020h Total length of data returned for this configuration.
1 01h Number of interfaces supported by this speed
configuration
1 01h Value to use to select configuration
1 00h Index of string descriptor describing configuration.
1 C0h Configuration characteristics
1 32h Maximum power consumption of the USB device from
the bus in this configuration when the device is fully
operational.
4. USB Descriptor Information
For example, if the device is currently operating at
Description
Description
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