Overview
Access types define the specific methods for reading and writing values for each data point in a solution, including polling rate, read on startup, and unsolicited input acceptance. The OnDisplayOrServer Access Type controls the data read and write permissions.
It is useful for projects with many communication points but not requiring constant data updates, reducing computational load, and improving performance. The OnDisplayOrServer On Display Or Server Access Type works by checking two conditions, OnDisplay On Display and OnServerOn Server, before permitting data read or write.
OnDisplay On Display means data can be read or written only when the display containing it is open, while OnServer means data can be read or written when the project is running as an OPC server.
On this page:
Table of Contents maxLevel 3
Creating
a New AccessTypeAn Access Types
To create or edit an AccessType:
Go toand configure an Access Type, follow these steps:
- Access Devices →
Customizing The Pre-Defined AccessTypes
- Access Types.
- Click on the plus icon.
- Fill all the property fields with you desired configuration (see the table below for more details about each option).
- Click Ok.
The following table describes each configuration property when creating an Access Type.
Field |
|---|
Our platform comes with several pre-defined access types that define the specific methods for reading and writing the values of each data point. To further optimize data exchange, users can customize these access types as needed. To customize pre-defined access types:
To configure access types:
Device AccessType Configuration Properties
Description | |
|---|---|
Name | Enter a name for this access type. |
Read | |
Read Polling | Select when you want to enable read polling. |
Read Polling Rate | Enter how often the address value is retrieved. |
Read Trigger | Enter an object property that tells the system when to read the value. |
On Startup | When selected, the system reads the value on startup. |
Write | |
Write Events | Select to enable the writing of values to the PLC. |
Write Event | Select when the value is written. |
WriteTrigger | Enter an object property that tells the system when to write the value. |
Settings | |
Accept Unsolicited | When selected, the system accepts values from the PLC, even if the polling time has not yet elapsed. |
Use Static Blocks | Select to use the block command field |
Block Command | Enter a definition for each block that will be created. Check the driver documentation to see if the specific driver uses this field and the valid values. |
Description | Enter a description for the access type. |
One very efficient AccessType is to only read data when it is being used by the application.
Unique Communication Tag Groups for Each AccessType:
A distinct feature of the platform's AccessTypes is their ability to generate unique tag groups for communication. This ensures that every AccessType gets its dedicated communication group, facilitating streamlined communication processes. It's crucial for users to recognize this differentiation when configuring or customizing AccessTypes.
On Display Or Server Acces Types
The On Display Or Server Access Type is
Configuring AccessType as OnDisplayOrServer
On the dialog window, you need to configure the ReadEnable field to OnDisplayOrServer.
This property is enough for the Reading portion of the communication. You can also enable Writing Events by selection the WriteEventEnable checkbox.
The OnDisplayOrServer AccessType s a great tool for projects that have a large amount of Communication Points but do not require the data to be constantly updated for all of them. It can help computers that lack computational power to handle a huge volume of data exchange while also maintaining other modules (Scripts, Alarms, etc) at the same time.
The OnDisplayOrServer On Display Or Server Access Type operation process can be divided into two aspects:
- OnDisplay
- OnServer
| Info |
|---|
ONLY when and while ANY of these options are met, the Communication Points with this AccessType can Read/Write data. |
On Display
The OnDisplay- On Display: The On Display part means that your Communication Point will only begin Reading/Writing when the Project display
- containing these tags is
- open.
- To illustrate, let us say we have a project with two displays: one for
- Line A and the other for
- Line B. Each display has its
- specific Tags added to it (Tag.LineAProduct1..., Tag.LineBP roduct1...)
- When the Project is running, there is no need to send/receive data for all Tags in the PLC. The Project only needs to send/receive data for the ones
- in the display
- currently opened on the Visualizer.
- So, when the LineA display is open, only LineA tags will communicate. The same goes for LineB.
Or Server
The OrServer or OPCServer- On Server: The OrServer or OPCServer means that if your Project
- runs as an OPC Server, the AccessType will behave as if
- its ReadEnable property is set
- to Always.
- Suppose you have the tags on the server
- side as Script Tasks, Classes, Expression, or Alarm Items
- . In that case, you must create a new AccessType specific for them with the ReadEnable option
- in Always.
Configuring The Acces Type as On Display Or Server
To configures an Access type as On Display Or Server, follow theses steps
- Access Devices → Access Types.
- Click on the plus icon.
- On the Read Polling property choose On Display Or Server. This property is enough for the Reading portion of the communication
- To Enable Writing Events check the Write Events box.
| Info |
|---|
ONLY when and while ANY of these options are met, the Communication Points with this Access Type can Read/Write data. |
In this section:
| Page Tree | ||||
|---|---|---|---|---|
|