Simulink Reference

Data Store Read

Read data from a data store

Library

Signal Routing

Description

The Data Store Read block copies data from the named data store to its output.

The data store from which the data is read is determined by the location of the Data Store Memory block or signal object that defines the data store. For more information, see Working with Data Stores and Data Store Memory.

More than one Data Store Read block can read from the same data store.

Note    Be careful when setting an execution priority on a Data Store Read block. Make sure that the block reads from the data store after the store is updated by any Data Store Write blocks that write to the store in the same time step.

Data Type Support

The Data Store Read block can output a real or complex signal of any data type supported by Simulink, including fixed-point data types.

For a discussion on the data types supported by Simulink, refer to Data Types Supported by Simulink in the Using Simulink documentation.

Parameters and Dialog Box

Data store name

Specifies the name of the data store from which this block reads data. The adjacent pull-down list lists the names of Data Store Memory blocks that exist at the same level in the model as the Data Store Read block or at higher levels. To change the name, select a name from the pull-down list or enter the name directly in the edit field.

When Simulink compiles the model containing this block, Simulink searches the model upwards from this block's level for a Data Store Memory block having the specified data store name. If Simulink does not find such a block, it searches the model workspace and the MATLAB workspace for a Simulink.Signal object having the same name. If Simulink finds the signal object, it creates a hidden Data Store Memory block at the model's root level having the properties specified by the signal object and an initial value of 0. If Simulink finds neither the Data Store Memory block nor the signal object, it halts the compilation and displays an error.

Data store memory block

This field lists the Data Store Memory block that initialized the store from which this block reads.

Data store write blocks

This parameter lists all the Data Store Write blocks with the same data store name as this block that are in the same (sub)system or in any subsystem below it in the model hierarchy. Double-click any entry on this list to highlight the block and bring it to the foreground.

Sample time

The sample time, which controls when the block reads from the data store. A value of -1 indicates that the sample time is inherited. See Specifying Sample Time in the online documentation for more information.

Characteristics

Sample Time	Specified in the Sample time parameter
Dimensionalized	Yes

See Also

Data Store Memory, Data Store Write

Data Store Memory

Data Store Write

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