> ## Documentation Index
> Fetch the complete documentation index at: https://dragonwingdocs-staging.qualcomm.com/llms.txt
> Use this file to discover all available pages before exploring further.

# History Buffer API

**Header:** `spf/api/modules/history_buffer_api.h`

## Structures

### `param_id_history_buffer_mode_t`

**Members**

<ParamField path="data_flow_mode" type="uint32_t">
  1: HISTORY\_BUFFER\_BATCHING sends the data to the client in batches.}
</ParamField>

<ParamField path="batch_size_ms" type="uint32_t">
  }
</ParamField>

## Type Definitions

### `param_id_history_buffer_mode_t`

```cpp theme={null}
typedef struct param_id_history_buffer_mode_t param_id_history_buffer_mode_t
```

## Macros

### `HISTORY_BUFFER_MAX_INPUT_PORTS`

```c theme={null}
#define HISTORY_BUFFER_MAX_INPUT_PORTS 1
```

### `HISTORY_BUFFER_MAX_OUTPUT_PORTS`

```c theme={null}
#define HISTORY_BUFFER_MAX_OUTPUT_PORTS 0
```

### `HISTORY_BUFFER_MAX_CONTROL_PORTS`

```c theme={null}
#define HISTORY_BUFFER_MAX_CONTROL_PORTS ( 1 )
```

### `HISTORY_BUFFER_MAX_INTENTS_PER_CTRL_PORT`

```c theme={null}
#define HISTORY_BUFFER_MAX_INTENTS_PER_CTRL_PORT ( 1 )
```

### `HISTORY_BUFFER_STACK_SIZE_REQUIREMENT`

```c theme={null}
#define HISTORY_BUFFER_STACK_SIZE_REQUIREMENT 4096 /* Bytes */
```

### `PARAM_ID_HISTORY_BUFFER_DETECTION_TRIGGER`

```c theme={null}
#define PARAM_ID_HISTORY_BUFFER_DETECTION_TRIGGER 0x08001B7E
```

### `PARAM_ID_HISTORY_BUFFER_FORCE_DRAIN_BATCH`

```c theme={null}
#define PARAM_ID_HISTORY_BUFFER_FORCE_DRAIN_BATCH 0x08001BF1
```

### `PARAM_ID_HISTORY_BUFFER_MODE`

```c theme={null}
#define PARAM_ID_HISTORY_BUFFER_MODE 0x08001B87
```

### `HISTORY_BUFFER_ON_DEMAND`

```c theme={null}
#define HISTORY_BUFFER_ON_DEMAND 0
```

### `HISTORY_BUFFER_BATCHING`

```c theme={null}
#define HISTORY_BUFFER_BATCHING 1
```

### `MODULE_ID_HISTORY_BUFFER`

```c theme={null}
#define MODULE_ID_HISTORY_BUFFER 0x07001182
```