> For the complete documentation index, see [llms.txt](https://support.powerio.com/hub/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://support.powerio.com/hub/codesys-hvac/en/hvac-knx-library/functionblocks/masterudp.md).

# MasterUDP

## `MasterUDP` (FB)

FUNCTION\_BLOCK MasterUDP IMPLEMENTS IKnxConnector

#### Overview

The MasterUDP function block serves as a KNX driver for communication with a KNX Net/IP gateway. It processes telegrams and coordinates communication with slave function blocks.

#### Inputs

| Inputs                   | Initial value                      | Description                         |
| ------------------------ | ---------------------------------- | ----------------------------------- |
| `xEnable`                | *TRUE*                             | Enable/disable the function block   |
| `sIPAddressKNXInterface` | *''*                               | IP address of the KNX interface     |
| `uiPortKNXInterface`     | *gc\_LibPara.gc\_uiPort*           | Port number of the KNX interface    |
| `itfNetworkInterface`    | -                                  | Network interface for communication |
| `uiPortPLC`              | *gc\_LibPara.gc\_uiPortLocal*      | Port number of the PLC              |
| `xResError`              | *FALSE*                            | Error reset flag                    |
| `tResponseTimeout`       | *gc\_LibPara.gc\_tResponseTimeout* | Timeout duration for requests       |

#### Outputs

* `xConnected` (BOOL): Connection status
* `itfKnxConnector` (IKnxConnector): Interface for slave blocks
* `udiConnectedSlaves` (UDINT): Number of connected modules
* `eStatus` (KnxStatus): Current KNX connection status
* `stDeviceInfo` (DeviceInfo): Device information
* `stKnxData` (KnxData): KNX data structure
* `bChannel` (BYTE): Communication channel identifier
* `eError` (ErrorKnx): Current error status
* `eLastError` (ErrorKnx): Last error

#### Usage

1. Configure the KNX interface with `sIPAddressKNXInterface` and `uiPortKNXInterface`.
2. Set `uiPortPLC` according to your PLC configuration.
3. Enable the block with `xEnable = TRUE`.
4. Monitor `xConnected` for the connection status.
5. Use `itfKnxConnector` to interact with slave function blocks.
6. Check `eStatus` and `eError` regularly.
7. Use `xResError` to reset error states.

#### Notes

* Ensure correct network settings (`itfNetworkInterface`) are set.
* Adjust `tResponseTimeout` adjust for network latency if needed.

InOut:

| Scope       | Name                     | Type                               | Initial                          | Comment                      |
| ----------- | ------------------------ | ---------------------------------- | -------------------------------- | ---------------------------- |
| Input       | `xEnable`                | `BOOL`                             | TRUE                             | On/Off                       |
| Input       | `sIPAddressKNXInterface` | `STRING`                           | ‘’                               | IP of the peer e.g. IP/Knx   |
| Input       | `uiPortKNXInterface`     | `UINT`                             | gc\_LibPara.gc\_uiPort           | Port of the peer e.g. KNX GW |
| Input       | `itfNetworkInterface`    | `IIoDrvEthernet.INetworkInterface` |                                  |                              |
| Input       | `uiPortPLC`              | `UINT`                             | gc\_LibPara.gc\_uiPortLocal      | Port of the controller       |
| Input       | `xResError`              | `BOOL`                             | FALSE                            | Error reset                  |
| Input Const | `tResponseTimeout`       | `TIME`                             | gc\_LibPara.gc\_tResponseTimeout | Timeout time for request     |
| Output      | `xConnected`             | `BOOL`                             |                                  |                              |
| Output      | `itfKnxConnector`        | `IKnxConnector`                    | THIS^                            | IF for comm. module FBs      |
| Output      | `udiConnectedSlaves`     | `UDINT`                            |                                  | Number of modules            |
| Output      | `eStatus`                | `KnxStatus`                        |                                  |                              |
| Output      | `stDeviceInfo`           | DeviceInfo                         |                                  |                              |
| Output      | `stKnxData`              | `KnxData`                          |                                  |                              |
| Output      | `bChannel`               | `BYTE`                             |                                  |                              |
| Output      | `eError`                 | ErrorKnx                           |                                  |                              |
| Output      | `eLastError`             | ErrorKnx                           |                                  |                              |


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