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WriteAsyncFcn

Callback function file to execute when asynchronous write completes

Description

You configure WriteAsyncFcn to execute a callback function file when an asynchronous write operation completes. You execute an asynchronous write with the writeasync function. A write async event occurs immediately after the server notifies the client that data has written to the device.

When a write async event occurs, the function specified in WriteAsyncFcn is passed two parameters: Obj and EventInfo. Obj is the object associated with the event, and EventInfo is an event structure containing the fields Type and Data. The Type field is set to 'WriteAsync'. The Data field contains a structure with the fields defined below.

FIeld Name

Description

LocalEventTime

The time, as a MATLAB® date vector, that the event occurred.

TransID

The transaction ID for the asynchronous write operation.

GroupName

The group name.

Items

A structure containing information about each item whose value or quality was written.

The Items structure contains the fields defined below.

FIeld Name

Description

ItemID

The item name.

Write async event information is stored in the EventLog property.

Characteristics

Access

Read/write

Applies to

dagroup

Data type

string, function handle, or cell array

Values

The default value is @opccallback.

See Also

Functions

opccallback, writeasync

Properties

EventLog

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