Properties
16 bit word Read-Write Starting address 0x40001 to 0x4FFFF when address mapping is active or 0 to FFFF when addressmapping deactivated
The HoldingRegister item type has the following properties:
| Name | Description | ID | Flags |
|---|---|---|---|
| Description | A description of what this item does. This is free text, so you can write anything you like here. | 101 | Persisted |
| Direction | Direction of data. Input (false) or Output (true). | 5040 | Persisted |
| Endian | Only valid when the Valuetype property is set to "Unicode String" or "ASCII". This property overrides the module's endian. Modbus is a "big-endian" protocol: that means the more significant byte of a 16-bit value is sent before the less significant byte. Be careful with 32-bit and 64-bit values, which may not be transferred using big-endian order. Some manufacturers treat 32-bit and 64-bit values as being composed of 16-bit words, and transfer the words in little-endian order. For example, the 32-bit value 0x12345678 would be transferred as 0x56 0x78 0x12 0x34. Select LittleEndian to use this mixed ordering. | 10012 | Persisted, Enumerated |
| EvaluationOrder |
What order to use to evaluate the values: Apis: The value is written to the slave on every cycle; Slave: The value is read from the slave before the write. The value is only written to the slave when its changed in Apis. | 10020 | Persisted, Enumerated |
| Modulus | Value = registerhigh x Modulus + registerlow. Valid only for 4 byte signed and unsigned int | 10015 | Persisted, Enumerated |
| Offset | The linear transformation addend to use when calculating and item value. (Value = RawValue * Scale + Offset) | 5006 | Persisted |
| Quality | Item quality - this tells you whether an item currently has a good or bad quality. It might be bad, for example, because it isn't connected or is set to the wrong type. | 3 | ReadOnly |
| Rights | Item access rights - this property may be "read", or "read write". This means that the property may only be read from, or also can be written to. For OPC items, this written value will be passed on to the external items this item comes from. | 5 | ReadOnly |
| Read single | Force master to read this item only in a single request. Used to optimize error handling. WARNING: Enabling this feature on numerous items will affect overall performance. | 10032 | Persisted |
| External quality tag | External tag overriding quality. | 10040 | Persisted |
| External quality mask | Bitmap representing quality bits field, when External quality tag is used. | 10041 | Persisted |
| External pattern bad quality | Bit pattern determinating bad quality, when External quality tag is used. | 10042 | Persisted |
| External mask unertain quality | Bit pattern determinating unsertain quality, when External quality tag is used. | 10043 | Persisted |
| Scale | The linear transformation multiplier to use when calculating the item value. (Value = RawValue * Scale + Offset) | 5005 | Persisted |
| Slaveaddress | The slave address (Unit ID) of the Modbus slave (overrides the module property). | 10030 | Persisted |
| SrcItemID | The item ID in the source. This is the item ID this item uses to fetch data from the source. | 5030 | Persisted |
| StringSize | The number of buffers to read. Only valid when "Valuetype" is "Unicode String" or "ASCII". | 10011 | Persisted |
| Time | The date and time when this item was last updated. | 4 | ReadOnly |
| Type | The item canonical data type - the specific type of this item. Whether it's an integer, string, date, etc. | 1 | ReadOnly |
| Unit | EU units - this is the unit this item value uses. For example: centimetres, kilograms, kilowatts, etc. | 100 | Persisted |
| Value | The current value of the item. | 2 | NormalPage |
| Valuetype | Item canonical datatype. This is the type of data the field holds. For example: integer, string, datetime, etc. | 10010 | Persisted, Enumerated |