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# Trigger

The `trigger` module provides classes for defining trigger conditions that can be used with both hardware captures and synthetic triggers.

## Overview

This module defines the trigger settings that determine when a capture should start or how a capture should be split. It currently supports edge triggers, which detect when a signal crosses a specified voltage threshold.

## Classes

### `EdgeTriggerDirection`

An enumeration that defines the direction of an edge trigger:

```python
class EdgeTriggerDirection(enum.Enum):
    RISING = "rising"   # Trigger when signal rises above threshold
    FALLING = "falling" # Trigger when signal falls below threshold
```

### `EdgeTrigger`

A dataclass that defines an edge trigger configuration:

```python
@dataclass
class EdgeTrigger:
    channel_index: Optional[int] = None
    channel_name: Optional[str] = None
    threshold_volts: float = 0.0
    direction: EdgeTriggerDirection = EdgeTriggerDirection.RISING
```

**Parameters:**
- `channel_index`: The channel number to trigger on (0-based index)
- `channel_name`: The name of the channel to trigger on
- `threshold_volts`: The voltage threshold that the signal must cross
- `direction`: Whether to trigger on rising or falling edges
- `holdoff`: Support coming soon!

**Note:** Either `channel_index` or `channel_name` must be provided, but not both. If both are provided, a warning will be logged.

## Example Usage

```{code-cell} python
from saleae import mso_api


# Create a trigger for rising edges on channel 1 at 0V
trigger = mso_api.EdgeTrigger(
    channel_index=1,
    threshold_volts=0,
    direction=mso_api.EdgeTriggerDirection.RISING
)
```

## Usage with Capture Configuration

Edge triggers can also be used with the `CaptureConfig` class to configure hardware-triggered captures:

```{code-cell} python
from saleae import mso_api


# Create a configuration for a triggered capture
config = mso_api.CaptureConfig(
    enabled_channels=[mso_api.AnalogChannel(channel=0, name="data")],
    analog_settings=mso_api.AnalogSettings(sample_rate=100e6),
    capture_settings=mso_api.AnalogTriggered(
        trigger=mso_api.EdgeTrigger(channel_name="data", threshold_volts=0),
        pre_trigger_seconds=0.0005,
        post_trigger_seconds=0.0005,
        timeout_seconds=1.0
    )
)
```