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# ACP_COMMAND_UPDATE_DMA_CONTEXT

> ACP_COMMAND_UPDATE_DMA_CONTEXT

Command for updating a DMA context.

## Syntax

```cpp theme={null}
typedef struct ACP_COMMAND_UPDATE_DMA_CONTEXT {  
    UINT32 contextIndex;  
    UINT32 updateMask;  
    APU_ADDRESS contextData;  
} ACP_COMMAND_UPDATE_DMA_CONTEXT  
```

### Members

*contextIndex*\
Type: UINT32

Index of a context to be updated.

*updateMask*\
Type: UINT32

One or more update flags.

| Flag | Value |
| - | - |
| SHAPE\_DMA\_UPDATE\_READ\_POINTER | 0x00000001 |
| SHAPE\_DMA\_UPDATE\_WRITE\_POINTER | 0x00000002 |
| SHAPE\_DMA\_UPDATE\_FULL | 0x00000004 |
| SHAPE\_DMA\_UPDATE\_ADDRESS | 0x00000008 |
| SHAPE\_DMA\_UPDATE\_NUM\_FRAMES | 0x00000010 |
| SHAPE\_DMA\_UPDATE\_FLOAT\_CONVERT | 0x00000020 |
| SHAPE\_DMA\_UPDATE\_NUM\_CHANNELS | 0x00000040 |
| SHAPE\_DMA\_UPDATE\_CHANNEL | 0x00000080 |
| SHAPE\_DMA\_UPDATE\_MASK | 0x000000ff |

*contextData*\
Type: APU\_ADDRESS

Physical address of the context data to be updated. Refer to the [SHAPE\_DMA\_CONTEXT](https://docs.xbox.com/reference/audio/shapedmacontext/structs/shape_dma_context.md) structure.

## Remarks

Used by `ACP_COMMAND_TYPE_UPDATE_DMA_CONTEXT` to update the specified DMA context. See the [ACP\_COMMAND\_TYPE](https://docs.xbox.com/reference/audio/acphal/enums/acp_command_type.md) enumeration. The context cannot be updated if it is already in the command queue.

## Requirements

**Header:** acphal.h

**Supported platforms:** XBOX One family consoles and XBOX Series consoles

## Conceptual documentation

* [ACP overview](https://docs.xbox.com/build/console-features/audio/overviews/acp-overview.md)

## See also

[ACP\_COMMAND\_TYPE](https://docs.xbox.com/reference/audio/acphal/enums/acp_command_type.md)\
[SubmitCommand](https://docs.xbox.com/reference/audio/acphal/interfaces/IAcpHal/methods/iacphal_submitcommand.md)\
[AcpHal](https://docs.xbox.com/reference/audio/acphal/acphal_members.md)


## Related topics

- [ACP overview](https://docs.xbox.com/build/console-features/audio/overviews/acp-overview.md)
- [ACP_COMMAND_TYPE](https://docs.xbox.com/reference/audio/acphal/enums/acp_command_type.md)
- [AcpHal](https://docs.xbox.com/reference/audio/acphal/acphal_members.md)
- [ACP_COMMAND_LOAD_SHAPE_FLOWGRAPH](https://docs.xbox.com/reference/audio/acphal/structs/acp_command_load_shape_flowgraph.md)
- [ACP_COMMAND_UPDATE_CONTEXTS](https://docs.xbox.com/reference/audio/acphal/structs/acp_command_update_contexts.md)