TM
Software – General Concepts
The General USB Process

How Does the Host Know a Device’s Requirements?

Device Descriptor
Configuration
Descriptor
Configuration
Descriptor
Interface
Descriptor
Endpoint
Descriptor
Endpoint
Descriptor
Interface
Descriptor
Endpoint
Descriptor
Endpoint
Descriptor
Interface
Descriptor
Endpoint
Descriptor
Endpoint
Descriptor
Interface
Descriptor
Endpoint
Descriptor
Endpoint
Descriptor

Upon detecting a USB device connection the host, using these

descriptors, configures the device and loads the proper driver program.

This configuration process is called “enumeration.”