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# mmioRead(atOffset:)

Reads data from the virtual graphics device’s memory-mapped I/O region.

```
func mmioRead(atOffset offset: Int) -> UInt32
```

## Parameters

`offset`

The offset into the MMIO bar to write to.

## Return Value

The 32-bit unsigned integer from the MMIO region.

## Discussion

Call this method whenever the guest virtual machine reads from the graphics device’s memory-mapped I/O region.

---

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