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# IOUSBEndpointDescriptor

The structure for storing an endpoint descriptor.

```
struct IOUSBEndpointDescriptor;
```

## Overview

For more information about this descriptor type, see section 9.6.6 of the USB 2.0 specification at <http://www.usb.org>.

## Topics

### Accessing the Descriptor Properties

[`uint8_t bLength;`](/documentation/USBDriverKit/IOUSBEndpointDescriptor/bLength)

The length of the descriptor in bytes.

[`uint8_t bDescriptorType;`](/documentation/USBDriverKit/IOUSBEndpointDescriptor/bDescriptorType)

The type of the descriptor.

[`uint8_t bEndpointAddress;`](/documentation/USBDriverKit/IOUSBEndpointDescriptor/bEndpointAddress)

The address of the endpoint.

[`uint8_t bmAttributes;`](/documentation/USBDriverKit/IOUSBEndpointDescriptor/bmAttributes)

The attributes of the endpoint.

[`uint16_t wMaxPacketSize;`](/documentation/USBDriverKit/IOUSBEndpointDescriptor/wMaxPacketSize)

The maximum packet size that the endpoint supports.

[`uint8_t bInterval;`](/documentation/USBDriverKit/IOUSBEndpointDescriptor/bInterval)

The interval to use when polling the endpoint for data transfers, specified in frames or microframes depending on the device’s speed.


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