Real-Time Systems

Presented by:

www.scisys.co.uk

Stuart D Fowell

SciSys SOIS Prototyping Activities

CCSDS Spring 2008 Meeting, Washington D.C, USA

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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Overview

SOIS Reference Implementation Complete SOIS architecture for evaluation &

feedback

GenFAS for MARC SOIS used as basis of Avionics

ASSERT & DisCo SOIS used as basis of Distributed Computing

Middlewares

Future Opportunities Flights?

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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SOIS Reference Implementation

SciSys (UK) and Astrium SAS (FR) Customer: ESA Jan – Oct 2008

Objectives: Prototype SOIS architecture over SpaceWire and

MIL-STD-1553B Investigate SOIS Plug-and-Play architecture on

SpaceWire Deploy on ESA’s RASTA Test Facility for future use Provide feedback on SOIS Red Books Provide draft Device Enumeration and Virtualisation

Red Books

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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SOIS Reference Implementation

Application Support Services: Asynchronous Messaging Service (subset) Command and Data Acquisition Services

Device Virtualisation Service (first prototype) Device Data Pooling Service Device Access Service Device Enumeration Service (first prototype)

File Services File Access Service File Management Service (File Transfer Service not addressed)

Time Access Service (Packet Store Service not addressed)

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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SOIS Reference Implementation

MIL-STD-1553B Subnetwork Services: Derived from ECSS 1553 Extensions WG Packet Service (Best Effort & Reserved QoS only) Memory Access Service Synchronisation Service (TIME primitives only) Device Discovery Service Test Service

SpaceWire Subnetwork Services: Derived from ECSS SpaceWire WG Packet Service (Best Effort & Assured QoS only) Memory Access Service (RMAP) Synchronisation Service (Simulation of SpaceWire

TimeCodes, TIME primitives only) Device Discovery Service (Test Service not addressed)

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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SOIS Reference Implementation

Reference Mission on ESA’s RASTA Test Facility LEON2 CPU, RTEMS RTOS, ANSI C

Data Storage InstrumentStar Tracker

Platform OBC Payload OBC

SpWRouter

MIL-STD-1553B

SpaceWire Link

SpaceWire Link

SpaceWire Link

SpaceWire Link

Control Momentum

Gyro

TM/TC Module

SpaceWire Link

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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MARC – Modular Architecture for Robust Computing Astrium Ltd (System, UK), SciSys (Software, UK), SEA

(Hardware, UK) Customer: ESA Oct 2007 – Mid 2009

Objective: Develop scalable decentralised Avionics and Payload

Control based on SpaceWire Network and SOIS

QoS Real-Time Command distribution using Reserved QoS Payload Data distribution using Best Effort/Assured QoS

CCSDS Packet distributed between software using AMS and Packet Service

AOCS Transducers accessed and controlled using CDAS and Packet/Memory Access Service

Onboard Time distributed and synchronised includes use of Synchronisation Service (SpaceWire TimeCodes insufficient to be soley used)

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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MARC – UNIONICS System Architecture

Copyright SEA Ltd.

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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MARC – GenFAS Software Architecture

Application Support Layer

File ServicesCommand & Data Acquisition Services

Sub-Network Layer

Physical Layer

Network Initialisation & Configuration

CPU RM Timer UART

SFGMSpaceWire TimeCode Register

EDAC Watchdog

Data Link Layer SpW Driver

Protocol Multiplexing Prioritisation

Packet Transfer Service

Get/SetService

Memory Access Service

Time Distribution

Service

Device Discovery Service

Test Service

Transfer Layer

Message Transfer Service

Device Access Service

Device Data Pooling Service

Device Virtualisation

Service

File Transfer Service

File Management

Service

File Access Service

Time Access Service

Ne

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rk Man

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ent S

ervices

Ha

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Op

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BS

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Transport Protocol

Network Protocol

System Functions andCommon Application ServicesLayer

Mode Manager

PUS Services

FDIR Manager

Configuration Manager

User Applications

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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MARC – Demonstrator Architecture

Copyright SEA Ltd.

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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ASSERT

Many European companies and academic institutes Customer: EC 50:50 funded under Framework 6 Sept 2004 – Oct 2007

Objective: Automated proof based System and Software Engineering

for Real-Time Applications

Distributed, Dependable, Hard Real-Time Virtual Machine

Middleware, RTOS, Communications Developed by ENST, UPM, UPD, SciSys and others…

Platforms Ada 2005, ANSI C, GNAT for LEON2, TSIM LEON2

Simulator, SpaceWire packet tunnelling over UDP/IP SOIS Prototypes:

Message Transfer Service over SpaceWire Packet Service (Best Effort and Assured QoS)

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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DisCo - Overview

Astrium SAS (System & Dem SW, FR), SciSys (Middleware SW, UK), consultancy from University of York and LAAS

Customer: ESA Jan 2005 – Jan 2008

Objective: Develop Distributed Computing Middleware for Payload

Control

Platforms: SpaceWire LEON2 (Pender Electronics), DSP (Dundee), PC ANSI C and RTEMS, VDP and Linux RTOS

SOIS prototypes – shared with GenFAS for MARC Message Transfer Service, Device Access Service, Device

Data Pooling Service , File Services, Time Access Service SpaceWire Packet (Best Effort and Assured QoS), Memory

Access, and Time Distribution Services

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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DisCo – Software Architecture

DisCo SOM

DisCo RSA

FDIRService

Basic S/W

SchedulingService

Configuration &Deployment

Service

InformationFlow

AuthorisationService

Device AccessService

Mass MemoryService

RemoteInvocation

Service

EventService

Time AccessService

Hardware

Functional interface Management interface

CommunicationsService

PMSpaceWire

RouterI/O

MassMemory

TM

RTOSSpaceWire

DriversI/O

Drivers

Payload SystemApplications

PayloadApplications

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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DisCo – Demonstrator Architecture

LEON

LEON

LEON

PC

DSPRtr

DSPRtr

DSPRtr

PC

LEON 3

LEON 2

LEON 1

DSP & router 1

DSP & router 2

DSP & router 3

USB to SpaceWire

Copyright Astrium SAS

SciSys SOIS Prototyping Activities - CCSDS Spring 200811th March 2008

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Future Opportunities

Follow-on to SOIS Reference Implementation Implementation of any missing services

E.g. EVENT.indication of Synchronisation Service

Integration into wider communications scenario simulation, inc. Space Link

Port to CAN? Fault tolerance? AOB

ExoMars Rover ESA Aurora Programme missionmission Phase B2 SOIS baselined for Rover Avionics by EADS Astrium

Ltd