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# tIOUSBHostConnectionSpeed

Constants indicating the connection speed of the device.

```
enum tIOUSBHostConnectionSpeed : unsigned int;
```

## Discussion

This enumeration matches the default speed ID mappings defined in XHCI 1.0 Table 147.

## Topics

### Getting the Connection Speeds

[`kIOUSBHostConnectionSpeedNone`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedNone)

No device is connected.

[`kIOUSBHostConnectionSpeedFull`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedFull)

The connected device runs at 12 megabits per second.

[`kIOUSBHostConnectionSpeedLow`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedLow)

The connected device runs at 1.5 megabits per second.

[`kIOUSBHostConnectionSpeedHigh`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedHigh)

The connected device runs at 480 megabits per second.

[`kIOUSBHostConnectionSpeedSuper`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedSuper)

The connected device runs at 5 gigabits per second.

[`kIOUSBHostConnectionSpeedSuperPlus`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedSuperPlus)

The connected device runs at 10 gigabits per second.

[`kIOUSBHostConnectionSpeedSuperPlusBy2`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedSuperPlusBy2)

The connected device runs at 20 gigabits per second.

[`kIOUSBHostConnectionSpeedCount`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedCount)

The number of available connection speed values.

### Enumeration Cases

[`kIOUSBHostConnectionSpeedOther`](/documentation/USBDriverKit/tIOUSBHostConnectionSpeed/kIOUSBHostConnectionSpeedOther)

---

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