# BELIMO\_EVXXX\_RX\_FW\_4\_2\_0\_MOD
## `BELIMO_EVXXX_RX_FW_4_2_0_MOD` (FB)
`FUNCTION_BLOCK` BELIMO\_EVXXX\_RX\_FW\_4\_2\_0\_MOD
### Representation
### Guidelines - software creation
The following function codes (FC) are supported: 3, 4 (additionally: 2, 4, 16)
For write operations to 32-bit data points (2 consecutive Modbus registers), FC16 must be used. No further registers may then 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, the address values must be used, not the register addresses. | | For unused registers, the value 65535 (dec.) is read / written.
* The calibration of the temperature sensors must be performed in the device; however, no adjustment is possible via Modbus.
* Modbus addresses 1 - 247 can be set directly in the integrated web server.
* All writable register addresses > 100 are persistent and must not be written cyclically
* The device firmware cannot currently (06.09.2024) be read from address 103. The value 0 is always read.
#### Notes on the input `rRelSetp` (Relative setpoint - position/volumetric flow/power in % (0.0 - 100.0 %))
1. The function ‘Volumetric flow depending on the signal `rRelSetp`’ is not linear!!! (See Belimo documentation)
2. The specification of an absolute volumetric flow setpoint can therefore be made as follows:
1. External PI controller (inverted, 0 - 100 percent): Actual value = `rAbsVolFlowUnit`, setpoint = desired absolute setpoint, control signal connect with input `rRelSetp` input.
2. Input `rRelSetp` assign constant 100.0, parameter `rMaxAbsVolFlowUnit` write with the desired absolute setpoint
{% hint style="danger" %}
Attention: The parameter `rMaxAbsVolFlowUnit` must not be written cyclically!!!
{% endhint %}
Measured values - adjustment: Class ???
InOut:
| Scope | Name | Type | Initial | Comment |
| ----------- | -------------------------- | ------------------------------------------------------------- | ---------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ |
| Input | `xEn` | `BOOL` | TRUE | Enable / disable communication (TRUE = enable) |
| Input | `byUnitId` | `BYTE` | 1 | Address of the device (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 xErrorCodeDev to the error-free state (on every rising edge)
Current state - type of the device (0 = Device not connected)
|
| Output | `eBusTermin` | BELIMO\_EVXXX\_RX\_FW\_4\_2\_0\_BUS\_TERMINATION | | Status of the Modbus termination resistor (Active = Enabled) |
| Output | `sSerialNum` | `STRING` | | Serial number of the device |
| Output | `wFirmwareVer` | `WORD` | | Firmware version of the device |
| Output | `eAO` | eManNum | eManNum.Auto |
Display - manual override on the device (actuator disconnected) (0 = Automatic)
|
| Output | `xSensorOffsetInDevice` | `BOOL` | |
Display whether the sensor adjustment must be performed in the device (TRUE = adjustment required in the device, FALSE = adjustment in the FB required)
Update interval for the processes influenced by the input xUpdateActual influenced
|
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