# On CAN Packet Received

## Overview

![The On CAN Packet Received Node.](/files/JVEg2lDkoR5ACDdy4Wrb)

**On CAN Packet Received** is an **Event Listener Node** allowing the user to perform an action once a **CAN** `Message` is selected from the **Drop-down Menu**.

[**Scope**](https://github.com/cgi-studio-gmbh/incari-doc/blob/2023.1/toolbox/communication/overview.md#scopes): **Project**, **Scene**.

## Attributes

![The On CAN Packet Received Node Attributes.](/files/MgYJX3EAEtlNpYO16fT6)

| Attribute       | Type          | Description                                                                                                                                                           |
| --------------- | ------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `On Change`     | **Bool**      | Specifies whether the **Node** executes when a **Packet**'s `Message` changes or simply when a **Packet**'s `Message` is received.                                    |
| `Configuration` | **Drop-down** | The identifying connection name that will be used, which is one that was set up in the [**Project Settings**](/incari-studio/2023.1/modules/project-settings/can.md). |
| `Message Name`  | **Drop-down** | A `Message` that is chosen from the uploaded *DBC* file. This is done in **Project Settings**.                                                                        |

## Outputs

| Output             | Type      | Description                                                                                                                            |
| ------------------ | --------- | -------------------------------------------------------------------------------------------------------------------------------------- |
| *Pulse Output* (►) | **Pulse** | A standard **Output Pulse**, to move onto the next **Node** along the **Logic Branch**, once this **Node** has finished its execution. |
| `Signal [n]`       | **Float** | The *Signal* or *Signals* of a *Message* from the specified *DBC* file.                                                                |

## Example

To visualize how the **Node** works a bit better, refer to the images below. The first is an example *DBC* file, which would have been added in the **CAN Project Settings**. There are two *Messages* and two *Signals*, each of which correspond to one of the *Messages*.

![DBC File Example.](/files/KVnOtrw3yvEc1zvf7I2f)

When the connection has been added in **Project Settings** and those changes are saved, the user can select the desired `Message Name` -- here Message1 -- which will make an output appear called `Signal1`. If a *Message* has multiple *Signals* -- for example if Message1 had two *Signals* called Signal1a and Signal1b -- all appear as outputs of the **Node**.

![On CAN Packet Received Node with Connection.](/files/QsA8BxJbhWlaUuN1z3nE)

## See Also

* [**On CAN Start**](/incari-studio/2023.1/toolbox/communication/can/events/oncanstart.md)
* [**On CAN Stop**](/incari-studio/2023.1/toolbox/communication/can/events/oncanstop.md)

## External Links

* The example [*DBC* file.](https://www.csselectronics.com/pages/can-dbc-file-database-intro)


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