# SimpleReadArray ## `SimpleReadArray` (FB) `FUNCTION_BLOCK` SimpleReadArray ### Representation
### **Triggering the transmission of Modbus data** The data transmission is triggered if at least one of the following conditions described below is met: Requirement: A suitable array is connected at the input `InputArray` connected. This is indicated by the output `xInputArrayValid` (= TRUE). 1. after an edge change at the input `xUpdateActual` (FALSE >> TRUE) (once) 2. after the elapsed time `tTimeUpdateActual` (`tTimeUpdateActual` > 0) (cyclic) 3. after a change in the array at the input `InputArray` (data type, size) (once) 4. after a change of essential parameters (`byUnitId`, `wRegisterAddr`, `eFunctionCode`) (once) 5. after an edge change at the input `xEn` (FALSE >> TRUE) (once) 6. after each cold start (once) After the completion of data transmission, the result is signaled (`xDataValid` = TRUE / FALSE) and the transmitted data in the array `InputArray` is stored. Note: The data type of the array at the input `InputArray` cannot be detected and evaluated as of 07/07/2023 (CDS-43675 Compiler, AnyType: Extension for Arrays needed) In the tool tip help for the input `InputArray` the possible array data types are displayed depending on the selected function code. InOut: | Scope | Name | Type | Initial | Comment | | ----------- | ------------------- | -------------------------------- | -------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | Input | `xEn` | `BOOL` | TRUE | Enable / disable communication (TRUE = enable) | | Input | `byUnitId` | `BYTE` | 0 | Modbus address of the device | | Input | `InputArray` | `__SYSTEM.AnyType` | |

Input for the array (FC01/02: ARRAY OF BOOL, ARRAY OF
BYTE) (FC03/04: ARRAY OF INT, ARRAY OF UINT, ARRAY OF WORD)

| | Input | `xUpdateActual` | `BOOL` | FALSE | Update of the actual values (on every rising edge) | | Input | `xResError` | `BOOL` | FALSE |

Reinitialization of the outputs eErrorCodeCom or
eErrorCodeDev to the error-free state (on every
rising edge)

| | Inout | `ModbusClient` | `ModbusClientBase` | | Client of the device | | Output | `eFunctionCodeFb` | ReadFunctionCodes | ReadFunctionCodes.FC01\_ReadCoils | Feedback - Modbus function code for the Modbus telegram | | Output | `wRegisterAddrFb` | `WORD` | 0 |

Feedback - start address of the register for the Modbus
telegram

| | Output | `diInputArrayNumb` | `DINT` | 0 | Number of array elements at the input `InputArray` depending on the Modbus function code | | Output | `xInputArrayValid` | `BOOL` | FALSE |

Validity of the array at the input InputArray (data type,
size) (FALSE = not valid, TRUE = valid)

| | Output | `xDataValid` | `BOOL` | FALSE |

Validity of the data in the array InputArray (FALSE = invalid,
TRUE = valid)

| | Output | `xAlarm` | `BOOL` | FALSE | Collective fault (TRUE = fault) | | Output | `xAlarmCom` | `BOOL` | FALSE | Collective fault - communication (TRUE = fault) | | Output | `eErrorCodeCom` | ModbusErrorCode | ModbusErrorCode.NO\_ERROR | Error code - communication (0 = no error) | | Output | `eErrorCodeDev` | SIMPLE\_READ\_ARRAY\_ERROR\_CODE | SIMPLE\_READ\_ARRAY\_ERROR\_CODE.NO\_ERROR | Error code - device (0 = no error) | | Output | `xBusy` | `BOOL` | FALSE | Communication display (TRUE = communication) | | Input Const | `eFunctionCode` | ReadFunctionCodes | ReadFunctionCodes.FC03\_ReadHoldingRegisters | Modbus function code for the Modbus telegram | | Input Const | `wRegisterAddr` | `WORD` | | Start address of the register for the Modbus telegram | | Input Const | `tTimeUpdateActual` | `TIME` | TIME#3s0ms |

Update interval for the processes influenced by the input
xUpdateActual influenced

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