> For the complete documentation index, see [llms.txt](https://docs.blynk.io/en/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.blynk.io/en/blynk-library-firmware-api/log-event.md).

# Log Event

## Get an Event code

1. Go to Device Template -> Events
2. Find the Event Code. Edit it if needed
3. Copy it to use in the firmware code below:

## Log Events from the device

Use `Blynk.logEvent` command to log events to the Blynk cloud.

```cpp
Blynk.logEvent("event_code");

// Also, you can add a custom description:
Blynk.logEvent("event_code", String("Temperature above threshold: ") + temp);
```

{% hint style="info" %}
The maximum allowed length of the description is 300 chars.

Messages with description that exceeds the 300 chars limit will be discarded.
{% endhint %}


---

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