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

2. ESA UNCLASSIFIED – For Official Use 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

3. ESA UNCLASSIFIED – For Official Use Cryosat

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

5. ESA UNCLASSIFIED – For Official Use Avionics 2015: RTU2015 1.Remote terminal unit acts as a data concentrator 2.Standard interface to OBC/CDMU with a standardized protocol 3.Standard Serial bus to devices 4.S/C may employ several miniaturised versions RTU Standard Digital Bus (SPI, I2C, …) Command and control Bus (Can, Milbus, SpaceWire) Sensors and Actuators M HK Module Motor Drive Module Micro Controller /FPGA Standard Interface Memory Aeronautics/Embedded examples of RTUs Digital Sensor bus

6. ESA UNCLASSIFIED – For Official Use RTU : possible configurations

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

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

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

10. ESA UNCLASSIFIED – For Official Use 1451 – use of TEDs

11. ESA UNCLASSIFIED – For Official Use 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 P/F Monitoring AOCS Sub-system CSS GPS STR RW MAG MTB P/L BC MM TTC RF Sub-system S band TX S band TX S band RX S band RX Mil-1553 bus CRS P/L C&C bus Payload Instruments P/L Essential Monitoring Payload Instruments Payload Instruments PDHT SpaceWire Traditional architecture

12. ESA UNCLASSIFIED – For Official Use IEEE 1451 standards

13. 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?

14. ESA UNCLASSIFIED – For Official Use Reference architecture

15. ESA UNCLASSIFIED – For Official Use 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 P/F Monitoring AOCS Sub-system CSS GPS STR RW MAG MTB P/L BC MM TTC RF Sub-system S band TX S band TX S band RX S band RX Mil-1553 bus CRS P/L C&C bus Payload Instruments P/L Essential Monitoring Payload Instruments Payload Instruments PDHT SpaceWire Traditional architecture

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