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# CAPLfunctionFDXSetByteOrder

# FDXSetByteOrder

[CAPL Functions](../../CAPLfunctions.md) » [General](../CAPLGeneralStartPage.md) » [Function Overview](../CAPLfunctionsGeneralOverview.md) » FDXSetByteOrder

**Valid for**: CANoe DE • CANoe:lite DE • CANoe4SW DE • CANoe4SW:lite DE

## Function Syntax

```
long FDXSetByteOrder(long fdxClientHandle, long byteOrder);
```

## Description

This function configures the byte order of the FDX protocol that should be used for the communication with the specified client. The default is Little Endian.

**Note**: With each received FDX datagram, your CANoe DE product automatically takes over the byte order from the datagram for the further communication with this client. The function `FDXSetByteOrder` is therefore only relevant in the rare case that CANoe DE product should send datagrams to an FDX client without having received a datagram from this client.

## Parameters

* **fdxClientHandle**: FDX client for which the byte order should be set.
* **byteOrder**:
  * 1: Little Endian
  * 2: Big Endian

## Return Values

* **0**: Successful function call
* **-1**: The parameter `fdxClientHandle` is invalid.
* **-1**: The parameter `byteOrder` is invalid.

## Example

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