> For the complete documentation index, see [llms.txt](https://docs.intrepidcs.com/neovi-api/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.intrepidcs.com/neovi-api/win32-api-overview-intrepidcs-api/structures-types-and-defines-overview-intrepidcs-api/setting-structures-overview-intrepidcs-api/sub-setting-structures-overview-intrepidcs-api/op_eth_settings-structure.md).

# OP\_ETH\_SETTINGS Structure

This structure defines various settings for OP BR Ethernet networks.

{% tabs %}
{% tab title="C/C++ Declare" %}

```cpp
typedef struct __declspec (align(2))
{
    unsigned char ucConfigMode;
    unsigned char preemption_en;
    unsigned char mac_addr1_0;
    unsigned char mac_addr1_1;
    unsigned char mac_addr1_2;
    unsigned char mac_addr1_3;
    unsigned char mac_addr1_4;
    unsigned char mac_addr1_5;
    unsigned char mac_addr2_0;
    unsigned char mac_addr2_1;
    unsigned char mac_addr2_2;
    unsigned char mac_addr2_3;
    unsigned char mac_addr2_4;
    unsigned char mac_addr2_5;
    unsigned char OpEthFlags;
    unsigned char Reserved;
}OP_ETH_SETTINGS;
```

{% endtab %}

{% tab title="Visual Basic .NET Declare" %}

```vbnet
<StructLayout(LayoutKind.Sequential, Pack:=2)> Public Structure OP_ETH_SETTINGS
    Dim ucConfigMode As Byte
    Dim preemption_en As Byte
    Dim mac_addr1_0 As Byte
    Dim mac_addr1_1 As Byte
    Dim mac_addr1_2 As Byte
    Dim mac_addr1_3 As Byte
    Dim mac_addr1_4 As Byte
    Dim mac_addr1_5 As Byte
    Dim mac_addr2_0 As Byte
    Dim mac_addr2_1 As Byte
    Dim mac_addr2_2 As Byte
    Dim mac_addr2_3 As Byte
    Dim mac_addr2_4 As Byte
    Dim mac_addr2_5 As Byte
    Dim OpEthFlags As Byte
    Dim Reserved As Byte
End Structure
```

{% endtab %}

{% tab title="C# .NET Declare" %}

```csharp
[StructLayout(LayoutKind.Sequential,Pack=2)]
public struct OP_ETH_SETTINGS
{
    public byte ucConfigMode;
    public byte preemption_en;
    public byte mac_addr1_0;
    public byte mac_addr1_1;
    public byte mac_addr1_2;
    public byte mac_addr1_3;
    public byte mac_addr1_4;
    public byte mac_addr1_5;
    public byte mac_addr2_0;
    public byte mac_addr2_1;
    public byte mac_addr2_2;
    public byte mac_addr2_3;
    public byte mac_addr2_4;
    public byte mac_addr2_5;
    public byte OpEthFlags;
    public byte Reserved;
}
```

{% endtab %}
{% endtabs %}

**Remarks**

| Item           | Description                                                     |
| -------------- | --------------------------------------------------------------- |
| ucConfigMode   | Sets the Link Mode. 0=Auto: 1=Master: 2=Slave                   |
| preemption\_en | Enables Preemption Support (IEEE802.3Br). 0=Disabled: 1=Enabled |
| mac\_addr1\_0  | First byte of Original MAC address XX:11:22:33:44:55            |
| mac\_addr1\_1  | Second byte of Original MAC address 00:XX:22:33:44:55           |
| mac\_addr1\_2  | Third byte of Original MAC address 00:11:XX:33:44:55            |
| mac\_addr1\_3  | Fourth byte of Original MAC address 00:11:22:XX:44:55           |
| mac\_addr1\_4  | Fifth byte of Original MAC address 00:11:22:33:XX:55            |
| mac\_addr1\_5  | Sixth First byte of Original MAC address 00:11:22:33:44:XX      |
| mac\_addr2\_0  | First byte of Spoof MAC address XX:11:22:33:44:55               |
| mac\_addr2\_1  | Second byte of Spoof MAC address 00:XX:22:33:44:55              |
| mac\_addr2\_2  | Third byte of Spoof MAC address 00:11:XX:33:44:55               |
| mac\_addr2\_3  | fourth byte of Spoof MAC address 00:11:22:XX:44:55              |
| mac\_addr2\_4  | Fifth byte of Spoof MAC address 00:11:22:33:XX:55               |
| mac\_addr2\_5  | Sixth byte of Spoof MAC address 00:11:22:33:44:XX               |
| OpEthFlags     | Bitfield of options                                             |
| Reserved       | Not Available                                                   |

| Item: Location                          | Function                                                  |
| --------------------------------------- | --------------------------------------------------------- |
| mac\_spoofing\_en: Bit 0                | State of enabling Mac Spoofing. 0=No Spoofing: 1=Spoof    |
| mac\_spoofing\_isDstOrSrc: Bit 1        | Spoof source or Destination 0=Destination: 1=Source       |
| Link\_Spd\_A: Bit 2 Link\_Spd\_B: Bit 3 | Sets Link Speed 0 0 = 10Mbps 0 1 = 100Mbps 1 0 = 1000Mbps |
| Q2112\_Phy\_Mode: Bit 4                 | Sets Phy Mode 0=IEEE: 1=Legacy                            |