eProsima Micro XRCE-DDS

eProsima Micro XRCE-DDS is a software solution that allows communicating eXtremely Resource Constrained Environments (XRCEs) with an existing DDS network. This implementation complies with the specification of the [eXtremely Resource Constrained Environments DDS (DDS-XRCE)](https://www.omg.org/spec/DDS-XRCE/) protocol as defined and maintained by the Object Management Group (OMG) consortium.

The eprosima Micro XRCE-DDS library implements a client-server protocol that enables resource-constrained devices (clients) to take part in DDS communications. The eProsima Micro XRCE-DDS Agent (server) acts as a bridge to make this communication possible. It acts on behalf of the Micro XRCE-DDS Clients by enabling them to take part to the DDS Global Data Space as DDS publishers and/or subscribers. It also allows for Remote Procedure Calls, as defined by the DDS-RPC standard, which implement a request/reply communication pattern.

eProsima Micro XRCE-DDS provides both a plug and play eProsima Micro XRCE-DDS Agent and an API layer which allows the user to implement the eProsimaMicro XRCE-DDS Clients.

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Main Features

High performance.

The eProsima Micro XRCE-DDS Client uses a static low-level serialization library (eProsima Micro CDR) that serializes in XCDR.

Low resources.

The Client library is dynamic and static memory free, as the only memory footprint is due to the stack growth. It can manage a simple publisher/subscriber with less of 2 kB of RAM. Besides, the Client is built according to a profiles concept, allowing to add or remove functionalities to/from the library at the same time as changing the binary size.

Multi-platform.

The OS dependencies are treated as pluggable modules, so that users can easily implement their platform-specific modules for the eProsima Micro XRCE-DDS Client library. By default, the project can run both over the standard Operating Systems Linux and Windows, and on the Real-Time Operating Systems Nuttx, FreeRTOS and Zephyr.

Compiler dependencies free.

The Client library uses pure C99 standard. No C compiler extensions are used.

Free and Open Source.

The Client library, the Agent executable, the generator tool and other internal dependencies as eProsima Micro CDR or eProsima Fast DDS are all free and open-source.

Easy to use.

The project provides several examples. This documentation guides the user step-by-step through some of them, namely how to create a publisher/subscriber, a requester/replier and a Peer-to-Peer publiser/subscriber Client example. An interactive demo can also be found to interact with the ShapesDemo application, useful to understand the DDS-XRCE protocol and to make tests. The Client API is thoroughly explained.

Implementation of the DDS-XRCE standard.

DDS-XRCE is a standard communication protocol by the OMG consortium focused on communicating eXtremely Resource Constrained Environments with the DDS world.

Best effort and reliable communication.

eProsima Micro XRCE-DDS supports both best-effort and reliable communication modes. The first implements a fast and light communication, while the second ensures reliability independently of the transport layer used underneath.

Pluggable transport layer.

eProsima Micro XRCE-DDS is not built over a specific transport protocol as Serial or UDP. It is agnostic about the transport used, and give the user the possibility of implementing the needed transport easily. By default, UPD, TCP, and Serial transports are provided. Also, an easy way to implement Custom transport is offered.

Commercial support

Available at support@eprosima.com

Installation

To install eProsima Micro XRCE-DDS, follow the instructions provided in the Installation page.

User manual

To test eProsima Micro XRCE-DDS, follow the Quick start instructions. This page shows how to create simple publisher/subscriber and requester/replier applications.

Additionally, there is an interactive example called Shapes Demo allowing users to create entities and to send/receive topics by instructions given by the command line. This example is useful to understand how the DDS-XRCE protocol interfaces with the DDS World.

To learn how to handle all the ingredients needed to create a Client, carefully read the Getting started page. This page describes how to use the eProsima Micro XRCE-DDS API in order to set up and run a Client application.

A generic introduction to the library can be found in the Overview page. To know more about Clients and Agents, find detailed information in the eProsima Micro XRCE-DDS Client and Client API pages, and in the eProsima Micro XRCE-DDS Agent and Agent API pages respectively.

eProsima Micro XRCE-DDS Gen

To create a serialization/deserialization topic code for the eProsima Micro XRCE-DDS Client, there is a tool called microxrceddsgen. Information about this tool can be found in the eProsima Micro XRCE-DDS Gen page.