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# InternalCombustionEngineControl (UORB message)

**TOPICS:** internal_combustion_engine_control

## Fields

| Name                   | Type      | Unit [Frame] | Range/Enum | Description                                                                                                                   |
| ---------------------- | --------- | ------------ | ---------- | ----------------------------------------------------------------------------------------------------------------------------- |
| timestamp              | `uint64`  |              |            | time since system start (microseconds)                                                                                        |
| ignition_on            | `bool`    |              |            | activate/deactivate ignition (spark plug)                                                                                     |
| throttle_control       | `float32` |              |            | setpoint for throttle actuator, with slew rate if enabled, idles with 0 [norm] [@range 0,1] [@uncontrolled NAN to stop motor] |
| choke_control          | `float32` |              |            | setpoint for choke actuator, 1: fully closed [norm] [@range 0,1]                                                              |
| starter_engine_control | `float32` |              |            | setpoint for (electric) starter motor [norm] [@range 0,1]                                                                     |
| user_request           | `uint8`   |              |            | user intent for the ICE being on/off                                                                                          |

## Source Message

[Source file (GitHub)](https://github.com/PX4/PX4-Autopilot/blob/main/msg/InternalCombustionEngineControl.msg)

::: details Click here to see original file

```c
uint64 timestamp        		# time since system start (microseconds)

bool ignition_on          		# activate/deactivate ignition (spark plug)
float32 throttle_control		# setpoint for throttle actuator, with slew rate if enabled, idles with 0 [norm] [@range 0,1] [@uncontrolled NAN to stop motor]
float32 choke_control			# setpoint for choke actuator, 1: fully closed [norm] [@range 0,1]
float32 starter_engine_control		# setpoint for (electric) starter motor [norm] [@range 0,1]

uint8 user_request			# user intent for the ICE being on/off
```

:::