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# MemoryWrite8

Writes an 8-bit value to the PCI device’s aperture at the specified memory index.

```
void MemoryWrite8(uint8_t memoryIndex, uint64_t offset, uint8_t data, IOOptionBits options);
```

## Parameters

`memoryIndex`

The index of the memory range from which to read.

`offset`

An offset from the beginning of the specified memory range.

`data`

The data that you want to write to the specified location.

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