Use of EDS for S/W Bus Adaptor CCSDS SOIS 2013 Spring Meeting Jonathan Wilmot NASA GSFC

Exemplar CFS Architecture Spacecraft Data Recorder Checksum Limit Checker CFDP File Transfer File Manager Stored Commanding Data Storage Instrument 1 Manager Instrument 2 Manager Scheduler Recorder Manager GNC Sensors Onboard Models 5 Hz GPS 232 GPS IO House keeping Software Bus Time Services Table Services Executive Event Health & Safety Control Law Altimeter 232 5 Hz Services Services Alt IO 422 50 Hz State Determination IMU LN200 IO Inter-task Message Router (SW Bus) Cnd Ingest EDAC Memory Scrubber Time Manager Space Wire Power Housekeeping Recorder 1553 Bus Controller Telemetry Output C&DH App GN&C App S/C Data CFS App RAM & EEPROM SBC 1553 Time HW SpaceWire Power hw S-Comm cFE App

CFS Software Bus (SB) CFS components publish/subscribe to CCSDS packets Packets are either telecommand or telemetry Publishers have no knowledge of subscribers One publisher to many subscribers is typical Control log, Fault management, data storage, telemetry output Send and forget Subscribers can request packet meta data (Publisher appid, system, subsystem) Subscriptions are based on packet app id (2^11) Common CFS applications use a consistent set of app ids, but missions can redefine them C structures are used in the software to extract packet data CCSDS headers are not part of the C structures but via abstractions Ad-hoc tools are used to convert between C structures and ground systems and tool databases Common definition parsed to generate packet definitions for other systems NASA working to establish CFS governance model and community Architecture, software, and tools commonality across many NASA missions Potential support for SOIS MTS compliance (Likely in the long term)

CFS Software Bus (SB) SB implements QOS only at the network interfaces SB API accepts QOS parameters and passes them down There is a Software Bus Network (SBN) component that plugs in for each network type (Ethernet, TTEthernet,1553, SpaceWire...) SBN is also used for interpartition (ARINC 653, PikeOS...), inter-core messaging (Multi-core), and intra-processor SB is not aware that SBN(s) exists SBN will pass network to network through traffic SBN implements a peer to peer network No protocol master, connection mappings are kept local Peers can come and go at runtime All subscription requests are replicated (This can have scaling issues) Ground interfaces are through Command Ingest and Telemetry Output plugins Not all components look at packet contents Data storage, telemetry output, both just filter and forward

Formats CFS may move toward the DEM format which moves beyond the 2^11 appid (topic) limitation Support for audio and video encapsulation CCSDS format Data Exchange message (DEM) format

EDS gets used in many places EDS(s) Subnetwork services Channelizations and service type (packet…) defined here Data Consumers I/O Schedule Device SpaceWire I/O Device Device specific driver(s) Device I/O Schedule device Raw Sensor processing device RIU Partition, core, network… device 1553 I/O Device Device Device I/O & Driver Software Bus Network (SBN) Software Bus Network (SBN) 422 Device

Use of EDS in the System Stack Layered Approach: Use of EDS in the System Stack HW and/or software logic SpaceWire 1553 Subnetwork I/O Sensor Processing Telemetry Output EDSes are incorporated into other EDSes up the stack. All of the spacecraft EDS eventually provide input into the ground systems and operational databases.

Meta data for file contents? End to End EDS EDS XTCE database EDS comm Telemetry monitors Control Center EDS Software Bus SOIS MTS EDS Star Tracker EDS Reaction Wheel EDS RTU driver EDS EDS File Manager EDS Command EDS Telemetry comm CFDP File Transfer EDS EDS EDS SOIS Stack HW RTU Mass Storage Meta data for file contents? XTEDS HW thermistor thermistor EDS 1451 HW 1451