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# KNX\_Write\_DPT\_2x

## `KNX_Write_DPT_2x` (FB)

FUNCTION\_BLOCK KNX\_Write\_DPT\_2x EXTENDS SlaveBasicWr

#### Overview

Send function for DPT 2.x (2-bit value).

#### Inputs

| Inputs                    | Initial value | Description                     |
| ------------------------- | ------------- | ------------------------------- |
| `xUpdateSetp`             | *FALSE*       | Trigger for target value update |
| `xValue`                  | -             | Main value to send (BOOL)       |
| `xPrio`                   | -             | Priority value to send (BOOL)   |
| `xWriteVisu`              | -             | Trigger for one-time send       |
| `eDPT_Format`             | -             | DPT 2.x format selection        |
| `byAdrGroup`              | *0*           | Group address (0-255)           |
| `byAdrMiddleGroup`        | *0*           | Middle group address (0-7)      |
| `byAdrMainGroup`          | *0*           | Main group address (0-31)       |
| `tTimeUpdateSetp`         | *T#0S*        | Cyclic update interval          |
| `tPauseTimeUntilNextSend` | *T#3S*        | Send pause                      |

#### Outputs

* `tNextWrite` (TIME): Time until the next write operation
* `xLastBusValue` (BOOL): Last received main value
* `xControlBit` (BOOL): Last received control bit (priority)

#### Usage

1. Select the DPT 2.x format with `eDPT_Format`.
2. Set the main value to send in `xValue` and the priority value in `xPrio`.
3. Configure the sending options:
   * For cyclic sending: `tTimeUpdateSetp` > T#0S
   * For event-based sending: Use `xUpdateSetp` or `xWriteVisu`
4. Monitor `xLastBusValue` for the last received main value.
5. Note `xControlBit` for the last received priority value.

InOut:

| Scope       | Name                      | Type            | Initial    | Comment                                                                                                                          | Inherited from |
| ----------- | ------------------------- | --------------- | ---------- | -------------------------------------------------------------------------------------------------------------------------------- | -------------- |
| Input       | `itfKnxConnector`         | `IKnxConnector` |            | <p>IMasterConnector interface input to register/unregister<br>the FB to the List on the Master</p>                               | SlaveBasicWr   |
| Input       | `xEnable`                 | `BOOL`          | TRUE       |                                                                                                                                  | SlaveBasicWr   |
| Output      | `sPhysicallAddressDevice` | `STRING(15)`    |            |                                                                                                                                  | SlaveBasicWr   |
| Output      | `sGroupAddress`           | `STRING(15)`    |            |                                                                                                                                  | SlaveBasicWr   |
| Input       | `xUpdateSetp`             | `BOOL`          | FALSE      | <p>Update of setpoints ( on each rising edge<br>)</p>                                                                            |                |
| Input       | `xValue`                  | `BOOL`          |            |                                                                                                                                  |                |
| Input       | `xPrio`                   | `BOOL`          |            |                                                                                                                                  |                |
| Input Const | `xWriteVisu`              | `BOOL`          |            | Read once                                                                                                                        |                |
| Input Const | `eDPT_Format`             | DPT\_2x         |            | Enum DPT\_2x                                                                                                                     |                |
| Input Const | `byAdrGroup`              | `BYTE`          | 0          | Groupaddress                                                                                                                     |                |
| Input Const | `byAdrMiddleGroup`        | `BYTE`          | 0          | Middle-Group-Address                                                                                                             |                |
| Input Const | `byAdrMainGroup`          | `BYTE`          | 0          | Main-Group-Adress                                                                                                                |                |
| Input Const | `tTimeUpdateSetp`         | `TIME`          | TIME#0ms   | <p>Update interval for the operations influenced by the input<br>‘xUpdateSetp’ 0 = no automatic<br>update, > 0 cyclic update</p> |                |
| Input Const | `tPauseTimeUntilNextSend` | `TIME`          | TIME#3s0ms | Pause after sending 0 = no pause                                                                                                 |                |
| Output      | `tNextWrite`              | `TIME`          |            |                                                                                                                                  |                |
| Output      | `xLastBusValue`           | `BOOL`          |            |                                                                                                                                  |                |
| Output      | `xControlBit`             | `BOOL`          |            |                                                                                                                                  |                |


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