> 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-modbus-library/functionblocks/belimo/belimo_epxxxx_fw_3_0_8_mod.md).
# BELIMO\_EPXXXX\_FW\_3\_0\_8\_MOD
## `BELIMO_EPXXXX_FW_3_0_8_MOD` (FB)
`FUNCTION_BLOCK` BELIMO\_EPXXXX\_FW\_3\_0\_8\_MOD
### **Display**
### Guidelines - Software creation
The following function codes (FC) are supported: 3, 4 (additionally: 2, 4, 16)
For write operations on 32-bit data points (2 consecutive Modbus registers), FC16 must be used. No further registers may be written in this telegram.
Format of 32-bit data points: Register+0 (LSW): H-byte L-byte Register+1 (MSW): H-byte L-byte
FC 02 may only be used for register 105 (Malfunction and service information, start address = 1664).
* For addressing, use the address information, not the register addresses.
* For unused registers, the value 65535 (dec.) is read / written
* Modbus addresses 1 - 247 can be set directly on the valve.
{% hint style="info" %}
All writable register addresses > 100 are persistent and must not be written cyclically
{% endhint %}
InOut:
| Scope | Name | Type | Initial | Comment |
| ----------- | ----------------------- | ------------------------------------------------ | --------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Input | `xEn` | `BOOL` | TRUE | Enable / disable communication (TRUE = enable) |
| Input | `byUnitId` | `BYTE` | 1 | Device address (1 .. 247) |
| Input | `xUpdateActual` | `BOOL` | FALSE |
Update of actual values (on every rising edge )
|
| Input | `xUpdateSetp` | `BOOL` | FALSE |
Update of setpoints (on every rising edge )
|
| Input | `xUpdateConfig` | `BOOL` | FALSE |
Update of the configuration (on every rising edge) (write and read access)
|
| Input | `xUpdateInfo` | `BOOL` | FALSE |
Update of the information (on every rising edge)
|
| Input | `xResError` | `BOOL` | FALSE |
Reinitialization of the outputs eErrorCodeCom or stErrorCodeDev to the error-free state (on every rising edge)
Position control: 0.0 - 100.0% refer to the relative position Flow rate control: 0.0 - 100.0% refer to the range 0 - Vmax (address 106) Forced override of the actuator signal - position/volume flow (0 = None)
|
| Input | `eCommand` | BELIMO\_EPXXXX\_FW\_3\_0\_8\_COMMAND | BELIMO\_EPXXXX\_FW\_3\_0\_8\_COMMAND.None | Command for service functions (0 = None) |
| Inout | `ModbusClient` | `ModbusClientBase` | | Client of the device |
| Output | `eSetpSourceFb` | BELIMO\_EPXXXX\_FW\_3\_0\_8\_SETPOINT\_SOURCE | |
Feedback - source for the setpoint - Position/volume flow (1 = Modbus)
Update interval for the processes that are influenced by the input xUpdateActual affected
|
---
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