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pageClass: is-wide-page
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# ButtonEvent (UORB message)
**TOPICS:** button_event safety_button
## Fields
| Name | Type | Unit [Frame] | Range/Enum | Description |
| ----------------------------------- | -------- | ------------ | ---------- | -------------------------------------- |
| timestamp | `uint64` | | | time since system start (microseconds) |
| triggered | `bool` | | | Set to true if the event is triggered |
## Constants
| Name | Type | Value | Description |
| ----------------------------------------------- | ------- | ----- | ----------- |
| ORB_QUEUE_LENGTH | `uint8` | 2 |
## Source Message
[Source file (GitHub)](https://github.com/PX4/PX4-Autopilot/blob/main/msg/ButtonEvent.msg)
::: details Click here to see original file
```c
uint64 timestamp # time since system start (microseconds)
bool triggered # Set to true if the event is triggered
# TOPICS button_event safety_button
uint8 ORB_QUEUE_LENGTH = 2
```
:::