# ChirpStack
## Configuring Uplinks
An uplink is a message your device sends to Datacake. To connect your ChirpStack server to Datacake, start by adding an HTTP Integration in your ChirpStack Application. Set the "Payload marshaler" to "JSON" and the Endpoint to
## Configure Downlinks
Downlinks are messages Datacake sends back to your devices. They are commonly used for configuration or setting outputs on your devices (where applicable).
To connect Datacake to your ChirpStack server, go to your device's configuration tab on Datacake and scroll down to the LoRaWAN section. There, click the "Change" button on the Network Server settings:
In the modal, enter the URL of your ChirpStack instance. Please include the protocol (e.g. `https://`) and do not add a trailing slash. A valid URL would for example look like this: `https://mychirpstack.com`.
Next, in order to add the ChirpStack API key, go back to your ChirpStack server and create a new API key.
You can give it an arbitrary name, for example "datacake". Click "Create API Key" and copy the now shown "Token".
{% hint style="info" %}
This token is only shown once. When you lose it, you have to delete and re-create the API Key.
{% endhint %}
Back on Datacake, paste this token into the "ChirpStack API Key" field and click the "Update" button.
That's it, Datacake is now successfully connected to ChirpStack and you can start receiving data from and sending data to your devices 🎉
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# Agent Instructions: Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.
Perform an HTTP GET request on the current page URL with the `ask` query parameter:
```
GET https://docs.datacake.de/lorawan/lns/chirpstack.md?ask=
```
The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.
Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.