If you are connected to a OPC server, the following will work:

■ If checked (default)

＜OPC＞

After the write is successful, a DataChange event occurs immediately and a notification of the change in value is sent to the upper level. Also, when reading the cache value, the value after writing is passed.

After writing is successful, an event such as ValueChange will occur. Also, when retrieving the value with ReadVal(DataSource = 1), the value after writing will be passed.

■ If not checked

＜OPC＞

The DataChange event will not occur until the cache is refreshed, either by automatic update or a Read request, and reading the cached value will return the previous value until the cache is refreshed.

Events such as ValueChange will not occur until the next read communication with the PLC is performed. The value of ReadVal(DataSource = 1) will also return the previous value until the cache is refreshed by the next read communication with the PLC.