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# IOUSBGetEndpointMaxPacketSize(_:_:)

Obtains the maximum packet size from an endpoint descriptor.

```
func IOUSBGetEndpointMaxPacketSize(_ usbDeviceSpeed: UInt32, _ descriptor: UnsafePointer<IOUSBEndpointDescriptor>!) -> UInt16
```

## Parameters

`usbDeviceSpeed`

The operational speed of the device.

`descriptor`

The endpoint descriptor to parse.

## Return Value

The maximum packet size in bytes.

## Discussion

This method parses an endpoint descriptor to determine its maximum packet size, which doesn’t include mult or burst factors.

---

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