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# CAPLfunctionFDXConfigureSequenceCounting

[Open topic with navigation](../../../../../CANoeDEFamily.htm#Topics/CAPLFunctions/Other/Functions/CAPLfunctionFDXConfigureSequenceCounting.md)

## CAPL Functions » General » Function Overview » FDXConfigureSequenceCounting

### FDXConfigureSequenceCounting

[Valid for](../../../Shared/FeatureAvailability.md): CANoe DE • CANoe:lite DE • CANoe4SW DE • CANoe4SW:lite DE

### Function Syntax

```plaintext theme={null}
long FDXConfigureSequenceCounting(long fdxClientHandle, long mode);
```

### Description

This function sets the behavior with which CANoe DE product should fill out the field **seqNrOrDgramLen** in the FDX datagram header.

Prerequisite for the function is to configure **UPD/IPv4** or **UDP/IPv6** as transport layer for the FDX feature.

### Parameters

* **fdxClientHandle**: FDX client for which the sequence counting should be configured.
* **mode**: Mode that should set for the Sequence Counting.
  * 0: Automatic mode (default for new connections)
    * The Sequence Counting automatically adapts to the FDX client.
  * 1: Enabled
    * The Sequence Counting is activated for the client.
  * 2: Disabled
    * The Sequence Counting is deactivated for this client.

### Return Values

* **0**: Successful function call
* **-1**: The parameter **fdxClientHandle** is invalid.
* **-2**: The parameter **mode** is invalid.
* **-3**: The configured transport layer does not support **Sequence Counting**.

### Example

[Coupling of two CANoe Instances using the FDX Protocol](../../../CANoeCANalyzer/Interfaces/FDXProtocolCouplingCANoeInstances.md)