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# ParameterUpdate (UORB message)

This message is used to notify the system about one or more parameter changes.

**TOPICS:** parameter_update

## Fields

| Name           | Type     | Unit [Frame] | Range/Enum | Description                              |
| -------------- | -------- | ------------ | ---------- | ---------------------------------------- |
| timestamp      | `uint64` |              |            | time since system start (microseconds)   |
| instance       | `uint32` |              |            | Instance count - constantly incrementing |
| get_count      | `uint32` |              |            |
| set_count      | `uint32` |              |            |
| find_count     | `uint32` |              |            |
| export_count   | `uint32` |              |            |
| active         | `uint16` |              |            |
| changed        | `uint16` |              |            |
| custom_default | `uint16` |              |            |

## Source Message

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

::: details Click here to see original file

```c
# This message is used to notify the system about one or more parameter changes

uint64 timestamp		# time since system start (microseconds)

uint32 instance		# Instance count - constantly incrementing

uint32 get_count
uint32 set_count
uint32 find_count
uint32 export_count

uint16 active
uint16 changed
uint16 custom_default
```

:::
