DDS Receive

Receive a DDS message

Since R2022b

• 

Libraries:
Simulink Real-Time / DDS

Description

The DDS Receive block receives a DDS message for a selected topic in the Simulink^® Real-Time™ model. The block allows you to attach a simulink data dictionary containing the DDS data definitions with the model.

The DDS Receive and DDS Send blocks let Simulink Real-Time applications communicate with Data Distribution Service (DDS) middleware applications through a shared Simulink data dictionary. These blocks are compatible with the DDS Blockset, which includes a DDS dictionary that lets you manage, create, and edit your DDS definitions in Simulink. You can import DDS specifications as XML files to create a skeleton Simulink model as a starting point for developing algorithms for DDS applications. For more information, see How Does DDS Blockset Work? (DDS Blockset).

The DDS Receive block receives a DDS message for a selected topic in the real-time application. You attach a Simulink data dictionary containing the DDS data definitions to the block. You can create a new data dictionary or associate an existing data dictionary to the block and select a topic, data writer path, and Quality of Service (QoS) from the data dictionary.

The DDS Receive block and DDS Send block have some limitations:

• You can use these blocks in the top level of a model. These blocks cannot be used in the referenced models.

• You can use these blocks in a real-time application. These blocks cannot be used for simulation in normal mode, accelerator mode, or rapid accelerator mode.

• You cannot use these blocks in protected models.

Examples

Communicate with Data Distribution Service (DDS) Middleware

Use Simulink Real-Time blocks to communicate using Data Distribution Service middleware.

• Open Script

Ports

Output

DDS Msg — DDS message

simulink message of Bus type

Returns the DDS message sent.

Parameters

Data Dictionary — Associate a data dictionary

string | char

Associate a simulink data dictionary containing dds data definitions or create a new data dictionary for the model.

Programmatic Use

Block Parameter: datadict

Topic — Select a topic name

string scalar | char vector

Select a topic from the drop-down menu for the data.

Programmatic Use

Block Parameter: topic

Reader XML Path — Data writer XML path

string (default)

select the data writer XML path.

Programmatic Use

Block Parameter: xmlPath

Reader QoS — Quality of service

string (default)

Select the quality of service from the drop-down menu.

Programmatic Use

Block Parameter: qos

Sample time — Sample time

-1 (default) | numeric

Enter the base sample time or a multiple of the base sample time. -1 means that the sample time is inherited.

Programmatic Use

Block Parameter: sampletime

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.

Version History

Introduced in R2022b