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# MemoryRead64

Reads a 64-bit value synchronously from the PCI device’s aperture at the specified memory index.

```
void MemoryRead64(uint8_t memoryIndex, uint64_t offset, uint64_t *readData);
```

## Parameters

`memoryIndex`

The index of the memory range from which to read.

`offset`

An offset from the beginning of the specified memory range.

`readData`

A variable in which to store the data. If this method encounters an error when reading the data, it sets the value to -1.

## Discussion

---

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