# Using a DetachedEncoder as a SPARK's feedback sensor

A DetachedEncoder, such as the MAXSpline Encoder, may be used as a `FeedbackSensor` for Closed Loop Control in SPARK MAX and SPARK Flex motor controllers.

This is configured in the `ClosedLoopConfig` class using the `feedbackSensor(FeedbackSensor, int)` or `feedbackSensor(FeedbackSensor, DetachedEncoder)` methods as follows:

{% tabs %}
{% tab title="Java" %}

```java
SplineEncoder spline = new SplineEncoder(12);
SparkFlex spark = new SparkFlex(1, MotorType.kBrushless);

SparkFlexConfig sparkConfig = new SparkFlexConfig();
sparkConfig.closedLoop
feedbackSensor(FeedbackSensor.kDetachedAbsoluteEncoder, spline);
  
// Continue with other configuration
```

{% endtab %}

{% tab title="C++" %}

```cpp
using namespace rev::detached;
using namespace rev::spark;

SplineEncoder m_spline{12};
SparkFlex m_spark{1, SparkFlex::MotorType::kBrushless};

SparkFlexConfig sparkConfig;
sparkConfig.closedLoop
  .SetFeedbackSensor(FeedbackSensor::kDetachedAbsoluteEncoder, spline);

// Continue with other configuration
```

{% endtab %}
{% endtabs %}

 


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