---
title: "mmioWrite(atOffset:value:)"
framework: Paravirtualized Graphics
role: symbol
role_heading: Instance Method
platforms: [Mac Catalyst 14.0+, macOS 11.0+]
path: "paravirtualizedgraphics/pgdevice/mmiowrite(atoffset:value:)"
---

# mmioWrite(atOffset:value:)

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

## Declaration

```swift
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

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

## See Also

### Handling Memory-Mapped I/O

- [mmioRead(atOffset:)](paravirtualizedgraphics/pgdevice/mmioread(atoffset:).md)