Microsoft OS Descriptors

Microsoft OS Descriptors

Updated: April 11, 2014

USB devices store standard descriptors in firmware for the device, and its interfaces and endpoints. Independent hardware vendors (IHVs) can also store class and vendor-specific descriptors. However, the types of information that these descriptors can contain is limited. IHVs typically must use Windows Update or media such as a CD to provide their users with a variety of device-specific information such as pictures, icons, custom drivers and so on.

To help IHVs address this issue, Microsoft has defined Microsoft OS descriptors. These descriptors can be used by IHVs to store in firmware much of the information that is now typically provided to customers separately. Versions of Windows that are aware of Microsoft OS descriptors use control requests to retrieve the information, and use it to install and configure the device without requiring any user interaction. This white paper provides an introduction to Microsoft OS descriptors, including a discussion of how they are stored and retrieved.

Note: The table of compatible and sub-compatible IDs in Appendix 1 of "Extended Compat ID OS Feature Descriptor Specification" is current as of the time the specification was written, but might have since changed. The following table contains the most recent list of compatible and sub-compatible IDs. All IDs must be eight bytes, so any unused characters are filled with NULLs.

CompatibleID

Sub-compatible ID

Description

(0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00)

(0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00)

No compatible or sub-compatible ID

"RNDIS"
(0x52 0x4E 0x44 0x49 0x53 0x00 0x00 0x00)

(0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00)

Remote Network Driver Interface Standard (RNDIS)

"PTP"
(0x50 0x54 0x50 0x00 0x00 0x00 0x00 0x00)

(0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00)

Picture Transfer Protocol (PTP)

"MTP"
(0x4D 0x54 0x50 0x00 0x00 0x00 0x00 0x00)

(0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00)

Media Transfer Protocol (MTP)

"XUSB20"
(0x58 0x55 0x53 0x42 0x32 0x30 0x00 0x00)

(0x00 0x00 0x00 0x00 0x00 0x00 0x00 0x00)

XNACC (Krypton)

"BLUTUTH"
(0x42 0x4C 0x55 0x54 0x55 0x54 0x48 0x00)

"11" (0x31 0x31 0x00 0x00 0x00 0x00 0x00 0x00)	Bluetooth radios compliant with v1.1 and compatible with the Microsoft driver stack
"12" (0x31 0x32 0x00 0x00 0x00 0x00 0x00 0x00)	Bluetooth radios compliant with v1.2 and compatible with the Microsoft driver stack
"EDR" (0x45 0x44 0x52 0x00 0x00 0x00 0x00 0x00)	Bluetooth radios compliant with v2.0 + EDR and compatible with the Microsoft driver stack

Bluetooth

"SCAN"
(0x53 0x43 0x41 0x4E 0x00 0x00 0x00 0x00)

Format as follows: 2 Letter vendor code + 1-5 ASCII characters* + 0x00

*ASCII restricted to uppercase letters, numbers, underscores.

Scan

"3DPRINT"
(0x33 0x44 0x50 0x52 0x49 0x4E 0x54 0x00)

Varies

MS3DPRINT G-Code 3D Printer

This information applies to Windows XP and later versions of Windows.