Adding client presets

Presets allow writing preset values to the target addressed data items upon right-click action (command). If needed, you can link the Write action of any preset container to other control logic. For example, you can link the Trigger slot of a TriggerSchedule into a ModbusClientPresetRegisters container component for periodic writes to its child preset registers based upon some repeating schedule.

In cases where you want to write preset values to specified coils and/or holding registers in a Modbus device using a linkable Write action, you can add special Preset components under the device. These are not actually proxy points—you need to copy them from the modbusAsync or modbusTcp palette. In rare cases, you may also wish to read/write string data from Modbus files in a device. The palettes also have a component especially for this application, which you can also copy under the Modbus device.

The Modbus Client Preset Coils preset contains a single ModbusClientPresetCoil to write to one coil—you can add additional (consecutive) coils using a built-in action
The Modbus Client Preset Registers preset contains a single ModbusClientPresetRegister to write to one holding register—you can add additional (consecutive) registers using a built-in action

NOTE: Modbus client preset components are not proxy points. There is no ProxyExt as data is not polled and read from the device—only written to it. You do not see them in any Modbus Client Point Manager view if you copy them under a client device’s Points extension. Presets exist for both Modbus coils and holding registers. These are the only two Modbus data items to which a Modbus master may write.

Instead of adding presets as described in this procedure, you can copy and paste already configured presets from another client Modbus device, if appropriate.

Perform the following steps:

Open the modbusAsyncor modbusTcp palette in the Palette side bar.
In the Nav side bar, expand the client Modbus network to show the Modbus device of interest.
Do one of the following:
- To configure coils or holding registers, drag or copy one of the preset container components to the Modbus device in the Nav side bar (or, to the property sheet view of that device, if open).
- To configure presets for both coils and holding registers, copy the entire Presets folder from the palette.
Since preset components are not proxy points, you should locate them elsewhere under the device.
NOTE: If using multiple preset containers under a client Modbus device, be careful not to overlap preset addresses. In other words, any specific preset address should be in only one preset container.
In the Name window, accept the default name or enter an alternate name, and click OK.

The folder is added under the device. By default it contains two preset containers, each with one preset entry—one for a preset coil, one for a preset holding register. Either preset container can be deleted (if not needed), or duplicated, as well as have additional preset entries added.
In any preset container, configure the Starting Address and other property values, and in its child preset entries (coil or register types), enter the actual preset values.

NOTE: You do not have to copy the entire Presets folder from the palette—this is just the easiest way to add both preset containers, each with a single preset entry child. You can locate preset containers anywhere under the Modbus device. However, be aware that if you copy these components under the Points container, they are not visible in any Modbus Client Point Manager view.
To add a preset to an existing Coil or Preset Register container, right-click the container and click Actions > Add Preset Coil Value or Actions > Add Preset Register Value.
The Add Preset ... window opens.
By default, added client preset components are appended to the bottom of the slot order.
To change the address order of the child presets relative to the absolute address in the preset container, right-click on a preset container and select Reorder.

Adding client presets

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