tubbz-alt / opensafety_demo

An openSAFETY Safe Node demo

Introduction {#mainpage}

[TOC]

Introduction {#sect_main_intro}

The openSAFETY_DEMO is an example implementation of an openSAFETY Safe Node (SN) with a simple GPIO application using POWERLINK as the underlying communication network. It is intended for people interested in openSAFETY and for evaluation purposes of openSAFETY.

\warning This demo only demonstrates the network capabilities and transport of openSAFEY frames. Additional software and hardware components are necessary to meet any necessary requirements demanded by notified bodies or related standards.

The demo application consists of one part for handling the POWERLINK communication (POWERLINK Communication Processor, PCP) which is implemented on a FPGA platform and a second part (application processor) executing the the user application, such as the openSAFETY stack and the safe application.

The user application part can be used in a single and a dual channelled configuration. The single channelled configuration uses one application processor, the dual channelled configuration additionally uses a second redundant application processor.

The partitioning of the system into application and network part allows a good separation of safety related and non-safety related code as well as the exchange of the underlying network interface.

Current version: \ref sect_rev_v121

openSAFETY_DEMO {#sect_main_sysdesc_oS_demo}

This section provides an overview of the openSAFETY_DEMO system components and how they interact with each other. The basic concept of the system is the clear separation of the network protocol and the user application. This is achieved by using a standalone processor for POWERLINK, called the POWERLINK Communication Processor (PCP), which is implemented on a Terasic DE2-115 FPGA board. The PCP handles the complete processing of the network protocol and provides a memory interface to forward the process and service data to the user application.

The second system part executes the user application, i.e. the openSAFETY stack and the safety application. It is implemented in two ways, as single channelled and as dual channelled system, using STMicroelectronics Nucleo boards: NUCLEO-F401RE or NUCLEO-F103RB.

The single channelled implementation comprises just one application processor, the dual channelled implementation additionally uses a second redundant application processor, which shares the SPI serial device with the other processor. The two processors receive the same data, exchange data among them and verify each others produced output.

System setup details of the dual channelled implementation are depicted in the next figure. For a single channelled application, the lower processor board on the right would not be part of the system.

@image latex system_overview.eps "Component overview of the openSAFETY_DEMO"

See \subpage page_gs_demo_detail for further information.

Protocol Stacks

This software distribution uses the POWERLINK and openSAFETY protocols as a basis for communication. More information about this protocols is provided in \ref page_protocols.

For processing the POWERLINK protocol on the PCP the open source protocol stack openPOWERLINK V2.x is used. This stack is already integrated in this distribution. For more information about openPOWERLINK checkout the doxygen documentation of the stack in the folder blackchannel/POWERLINK/stacks/openPOWERLINK/doc.

The openSAFETY protocol stack is processed on the application processor. This open source stack can be downloaded from https://sourceforge.net/projects/opensafety/.

License {#sect_main_license}

The openSAFETY_DEMO is open-source software (OSS) and is licensed under the BSD license. Please refer to the file's header and the file ["license.md"](\ref page_licenses) for the applicable license and the corresponding terms and conditions.

Documentation {#sect_main_documentation}

Scope of the openSAFETY_DEMO Documentation {#sect_main_documentation_scope}

This documentation provides demo-specific information on the used hard- and software, how to put the demo into operation and the demo's customisation possibilities. With SN development in mind, this documentation also gives generalised information on the hardware design, software design and the software API of the interface between the POWERLINK Communication Processor (PCP) and the user application.

Location and Generation {#sect_main_documentation_location_generation}

• The documentation of the openSAFETY_DEMO is located in the subdirectory "doc". It is written in markdown format and can be read by opening the .md with a text editor.

• The software manual can be generated from the markdown documentation and the in source-code documentation with the tools Doxygen and CMake. Therefore Doxygen version greater or equal 1.8 is required. The software manual will be created in HTML format under build/doc/html. [Graphviz] (https://www.graphviz.org/) is used for generating graph visualisations and diagrams.

  To generate the documentation enter the following commands according to your host operating system.

Build command on Windows {#sect_main_build_doc_windows}

One possibility for building the documentation is to use MinGW and MSYS. When installed, open a MSYS terminal and carry on with the steps mentioned in \ref sect_main_build_doc_linux.

Another possibility is to use the tools of a Visual Studio installation. Open the Visual Studio Command Prompt, change to the openSAFETY_DEMO root directory and enter the following commands:

  > cd build
  > cmake -G"NMake Makefiles" ../
  > nmake doc

Build command on Linux {#sect_main_build_doc_linux}

Open a terminal where the path to make, doxygen and CMake is set, change to the openSAFETY_DEMO root directory and enter the following commands:

  > cd build
  > cmake -G"Unix Makefiles" ../
  > make doc

Support {#sect_main_support}

Support on openSAFETY Demo is available via the online discussion forums on the SourceForge project page:

• [Discussion] (https://sourceforge.net/p/opensafetydemo/discussion/)

Download {#sect_main_download}

The openSAFETY_DEMO can be obtained from its SourceForge project site, GitHub and via git:

• SourceForge https://sourceforge.net/projects/opensafetydemo/

• GitHub https://github.com/OpenAutomationTechnologies/openSAFETY_DEMO

• git

  For cloning the openSAFETY_DEMO repository and all necessary submodules execute the following statements:

   > git clone --recursive https://github.com/OpenAutomationTechnologies/openSAFETY_DEMO.git openSAFETY_DEMO
   > cd openSAFETY_DEMO
   > git checkout -b mybranch tags/V1.2.1 && git submodule update --recursive