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# mmioWrite(atOffset:value:)

Writes data to the virtual graphics device’s memory-mapped I/O region.

```
func mmioWrite(atOffset offset: Int, value: UInt32)
```

## Parameters

`offset`

The offset into the MMIO bar to write to.

`value`

The value to write to memory.

## Discussion

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

---

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