# Check Stop

In your testplan you can place a **LTT Check Stop** check wherever you want. It checks if there is a stop request from the user interface, initiated by the user pressing F1 or F8. If this is the case, the step will **jump to the cleanup section** of the currently executing TestStand sequence.

![Check Stop](/files/ET4QAqHfCnkr58FtXVmv)

A **check for stop** is necessary to react to **user stop requests** and **TCC value changes**. By default, the only check for stop is done in [MainSequence](/ltt/documentation/ltt-gui-manual/teststand/processmodel/orderofexecution.md). This means:

* The test execution will only stop after an operation mode sequence returns, which can take a long time or not happen at all.
* The testplan can only react to a [TCC value change](/ltt/documentation/ltt-gui-manual/teststand/operationmodes.md) when the current operation mode is finished.

Both may or may not be desired behavior.

{% hint style="info" %}
Be aware that **LTT Check Stop** only jumps to cleanup of the current sequence. If you are in some nested sequence you will need to place a **LTT Check Stop** in each sequence all way up to your [operation mode sequence](/ltt/documentation/ltt-gui-manual/teststand/operationmodes.md) entry point.
{% endhint %}

***

* [Read more about other stop criteria](/ltt/documentation/ltt-gui-manual/teststand/processmodel/orderofexecution.md#STOP_CONDITIONS)
* [Read more about station control](/ltt/documentation/ltt-gui-manual/lttgui/stationcontrol.md)


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