Input to CCSDS P&P WG Chris Taylor CCSDS 2011 Berlin

Introduction In reviewing the IEE1451 and CANOpen specs for the use of EDS, it is apparent that certain architectures are assumed by the standards These architectures influence the point at which interfaces are exposed and the application of the EDS In particular, both 1451 and CANopen assume an intelligent controller which insulate the host software from underlying details of the connected sensors and actuators Such an architecture is similar to that being proposed by ESA for a standard building block Remote Terminal Unit (RTU) – essentially a data concentrator We need to take account of these architectures both to ensure that SOIS is compatible but also to understand the use of EDS ESA UNCLASSIFIED – For Official Use

Cryosat ESA UNCLASSIFIED – For Official Use

RTU as element of P/F Avionics: MMU P/L SpW, HSSL,SpF P/L MIL-STD-1553B, CAN, SpW P/L Bus CDMU MIL-STD-1553B CAN RS-422 SpW ECSS-E-ST-50-13C ECSS-E-ST-50-12C,… ECSS-E-ST-50-15dr ECSS-E-ST-50-14C ECSS for digital sensor busses RTU P/F Bus RTU2015 PCU/PCDU Sensors & Actuators (T, AOCS, Propulsion, …) Power Bus Load ESA UNCLASSIFIED – For Official Use

Avionics 2015: RTU2015 Command and control Bus (Can, Milbus, SpaceWire) Remote terminal unit acts as a data concentrator Standard interface to OBC/CDMU with a standardized protocol Standard Serial bus to devices S/C may employ several miniaturised versions RTU Micro Controller/FPGA Standard Interface Memory Memory Digital Sensor bus HK Module Motor Drive Module Standard Digital Bus (SPI, I2C, …) M Sensors and Actuators Aeronautics/Embedded examples of RTUs ESA UNCLASSIFIED – For Official Use

RTU : possible configurations ESA UNCLASSIFIED – For Official Use

EDS EDS EDS Mem contr EDS EDS CDMU RTU DVS Virtual Functional Device Serial 1 Wire I2C EDS EDS DVS Virtual EDS Functional Mem contr EDS Device Access protocol DAS Data link any EDS Device Access protocol DAS Data link any CDMU RTU ESA UNCLASSIFIED – For Official Use

EDS EDS EDS EDS Mem contr EDS EDS CDMU RTU DVS Virtual Functional Serial 1 Wire I2C EDS EDS DVS Virtual EDS EDS Functional Functional Mem contr EDS EDS Device Access protocol DAS Data link any Device Access protocol DAS Data link any CDMU RTU ESA UNCLASSIFIED – For Official Use

IEEE 1451 – “RTU Architecture” ESA UNCLASSIFIED – For Official Use

1451 – use of TEDs ESA UNCLASSIFIED – For Official Use

Traditional architecture P/L C&C bus Payload Instruments P/L Essential Monitoring PDHT SpaceWire Thermal P/F POWER S/S PCDU Propulsion Sub-system Thrusters Tank Pt Thermistors Heaters 1553 BC TM Encoder TC Decoder OBT SMU Platform CPDU P/F ON/OFF HLC PM TC Management TM Management OBT Management FDIR Management MdM Management AOCS Management Power Management Thermal Management Payload management Security Module PPS RM Alarms LV Discrete I/Os SADM Monitoring AOCS Sub-system CSS GPS STR RW MAG MTB P/L MM TTC RF Sub-system S band TX RX Mil-1553 bus CRS ESA UNCLASSIFIED – For Official Use

IEEE 1451 standards ESA UNCLASSIFIED – For Official Use

Questions for SOIS WG IEEE1451 use the same architecture as the proposed ESA RTU. 1451 uses XTEDS for devices but presents a standard API for access over the user network – How does this fit with the SOIS P&P architecture, in particular the DAS and DVS ESA is also standardising the use of CANBus as a primary onboard bus. CANBus has its own (text based) EDS – how does this fit with the SOIS P&P architecture? (important as use of CAN will force equipment suppliers to provide EDS’s) There are several “object dictionaries” (1451, CAN, XTEDS) available – how (should we) do we rationalise these into a single view and document? Our diagrams to not yet reflect the use of a device specific protocol to support the device access service – propose this should be identified/specified as this will be needed e.g. for standard access to an RTU The SPA guidebook contains a section on SOIS – is everybody happy that the text correctly reflects the comparison with SPA? The Green book has been updated, are there still actions and updates and what are the plans for the review and release? Although we made a great step forwards at the last meeting and reflected the results in the Green book, I’m concerned that the GB text is a little ‘academic’ and would benefit from a practical example to supplement the layered model – comments anyone? ESA UNCLASSIFIED – For Official Use

Reference architecture ESA UNCLASSIFIED – For Official Use

Traditional architecture P/L C&C bus Payload Instruments P/L Essential Monitoring PDHT SpaceWire Thermal P/F POWER S/S PCDU Propulsion Sub-system Thrusters Tank Pt Thermistors Heaters 1553 BC TM Encoder TC Decoder OBT SMU Platform CPDU P/F ON/OFF HLC PM TC Management TM Management OBT Management FDIR Management MdM Management AOCS Management Power Management Thermal Management Payload management Security Module PPS RM Alarms LV Discrete I/Os SADM Monitoring AOCS Sub-system CSS GPS STR RW MAG MTB P/L MM TTC RF Sub-system S band TX RX Mil-1553 bus CRS ESA UNCLASSIFIED – For Official Use

Avionics 2015: Platform S/s and I/Fs P/L Bus OBC/CDMU/ SMU Sensors & Actuators (T, AOCS, Propulsion, …) P/F Bus TX RTU RTU analog digital PCDU MIL-STD-1553B (CAN) Propulsion AOCS Sensors & actuators AOCS Sensors & actuators ESA UNCLASSIFIED – For Official Use