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# HwActivate

Opens the communication channel to the device.

```
virtual kern_return_t HwActivate();
```

## Return Value

<doc://com.apple.documentation/documentation/DriverKit/kIOReturnSuccess> on success, or another value if an error occurs. See <doc://com.apple.documentation/documentation/DriverKit/error-codes>.

## Discussion

Override this method and use your implementation to prepare the device’s hardware for serial communication. Always call the `super` version of the method at the beginning of your implementation.

---

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