Device Classes
The functionality of USB devices is defined by class codes, communicated to the USB host to affect the loading of suitable software driver modules for each connected device. This provides for adaptability and device independence of the host to support new devices from different manufacturers.
Device classes include:
| Class | Usage | Description | Examples, or exception |
|---|---|---|---|
| 00h | Device | Unspecified | Device class is unspecified, interface descriptors are used to determine needed drivers |
| 01h | Interface | Audio | Speaker, microphone, sound card, MIDI |
| 02h | Both | Communications and CDC Control | Modem, Ethernet adapter, Wi-Fi adapter |
| 03h | Interface | Human interface device (HID) | Keyboard, mouse, joystick |
| 05h | Interface | Physical Interface Device (PID) | Force feedback joystick |
| 06h | Interface | Image | Webcam, scanner |
| 07h | Interface | Printer | Laser printer, inkjet printer, CNC machine |
| 08h | Interface | Mass storage (MSC or UMS) | USB flash drive, memory card reader, digital audio player, digital camera, external drive |
| 09h | Device | USB hub | Full bandwidth hub |
| 0Ah | Interface | CDC-Data | Used together with class 02h: communications and CDC control |
| 0Bh | Interface | Smart Card | USB smart card reader |
| 0Dh | Interface | Content security | Fingerprint reader |
| 0Eh | Interface | Video | Webcam |
| 0Fh | Interface | Personal Healthcare | Pulse monitor (watch) |
| DCh | Both | Diagnostic Device | USB compliance testing device |
| E0h | Interface | Wireless Controller | Bluetooth adapter, Microsoft RNDIS |
| EFh | Both | Miscellaneous | ActiveSync device |
| FEh | Interface | Application-specific | IrDA Bridge, Test & Measurement Class (USBTMC), USB DFU (Direct Firmware update) |
| FFh | Both | Vendor-specific | Indicates that a device needs vendor specific drivers |
Read more about this topic: Universal Serial Bus
Famous quotes containing the words device and/or classes:
“Syntax is the study of the principles and processes by which sentences are constructed in particular languages. Syntactic investigation of a given language has as its goal the construction of a grammar that can be viewed as a device of some sort for producing the sentences of the language under analysis.”
—Noam Chomsky (b. 1928)
“Classes struggle, some classes triumph, others are eliminated. Such is history; such is the history of civilization for thousands of years.”
—Mao Zedong (1893–1976)