SOIS EDS ESA Internal Study YGT Program F. Torelli & P. Skrzypek CCSDS Fall Meeting 2012 15/10/2012

Introduction Outline Overview of the SOIS EDS study Recap on basic SOIS concepts Points currently under investigation Driver/device behavioural model in SOIS EDS Algorithms representation in SOIS EDS Objectives: Overview of the SOIS EDS Study Basic SOIS EDS concepts Points of discussion regarding: Device behavioural model Behavioural model representation in EDS

Overview of the SOIS EDS study

SOIS EDS study Young Graduate Trainee: MSc in Informatics, spec. Computer Engineering Experience in OS porting, drivers development, sensors wireless networks development and testing 1 year, full time Objectives: SOIS EDS technology and schema assessment. EagleEye AOCS ICDs translation into SOIS EDS. DVS and DAS auto-coding and integration into EagleEye Central SW EagleEye AOCS performance verification

EagleEye and Avionics Test Bench SOIS EDS from AOCS equipment SOIS DAS & DVS into Central SW

Recap on basic SOIS concepts

SOIS Command & Data Acquisition Service Primitives Application ACQUIRE_FROM_DEVICE.request (DASAP Address, Transaction Identifier, Device Identifier, Value Identifier) ACQUIRE_FROM_DEVICE.indication (DASAP Address, Transaction Identifier, Value, Result Metadata, Timestamp (optional)) COMMAND_DEVICE.request (DASAP Address, Transaction Identifier, Device Identifier, Value Identifier, Value) COMMAND_DEVICE.indication (DASAP Address, Transaction Identifier, Result Metadata) DVS Service Primitives Device Abstraction Control Procedure ACQUIRE_FROM_DEVICE.request (Transaction Identifier, Virtual Device Identifier, Value Identifier) ACQUIRE_FROM_DEVICE.indication (Transaction Identifier, Value, Result Metadata, Timestamp (optional)) COMMAND_DEVICE.request (Transaction Identifier, Virtual Device Identifier, Value Identifier, Value) COMMAND_DEVICE.indication (Transaction Identifier, Result Metadata) DAS Service Primitives Device-specific Access Protocol PACKET_SEND.request (PSSAP Address, PDSAP Address, Service Class, Priority, Channel, Data) PACKET_RECEIVE.indication (PSSAP Address, PDSAP Address, Service Class, Channel, Data) PACKET_FAILURE.indication (PSSAP Address, PDSAP Address, Failure Metadata) READ.request (MASAP Address, Destination Address, Transaction ID, Memory ID, Start Memory Address, Size, Priority, Channel, Authorisation (optional)) READ.indication (MASAP Address, Destination Address, Transaction ID, Memory ID, Start Memory Address, Size, Priority, Channel, Data, Result Metadata) WRITE.request (MASAP Address, Destination Address, Transaction ID, Memory ID, Start Memory Address, Size, Priority, Channel, Data, Acknowledge (optional), Authorisation (optional), Verification (optional)) READ/MODIFY/WRITE.request (MASAP Address, Destination Address, Transaction ID, Memory ID, Memory Address, Size, Mask, Priority, Channel, Data, Acknowledge (optional), Authentication (optional), Verification (optional)) MEMORY_ACCESS_RESULT.indication (MASAP Address, Destination Address, Transaction ID, Memory ID, Start Memory Address, Size, Result Metadata) SubNet PS & MAS Service Primitives ECSS Protocol Datalink

SOIS Command & Data Acquisition Procedures & Protocols Application DVS Service Primitives Device Abstraction Control Procedure Non-Standard Procedure, it depends on the device/equipment DAS Service Primitives Device-specific Access Protocol Non-Standard Protocol, it depends on the device/equipment SubNet PS & MAS Service Primitives ECSS Protocol Datalink MilBus 1553 communication protocol service primitives and engine [ECSS-E-ST-50-13C] Spacewire RMAP service primitives and engine [ECSS-E-ST-50-52C] Others…

SOIS Command & Data Acquisition Electronic Data Sheets Application SOIS DoT Terms DVS Service Primitives Device Abstraction Control Procedure Service Primitives Semantics SOIS EDS Code Generation Service capability DAS Service Primitives Device-specific Access Protocol Information to generate DACP Code Generation Mapping between DACP and DAS Primitives SubNet PS & MAS Service Primitives ECSS Protocol Datalink Information to generate DAP No need for ECSS protocol description in the SOIS EDS Mapping between DSAP and SubNet Primitives

Points currently under investigation

Behavioural Model Options A. Driver behaviour EDS includes the DACP and DAP algorithms DVS and DAS SW is the translation of the EDS algorithms B. Device behaviour EDS includes manufacturer behaviour state chart Code generator produces the DVS and DAS SW SOIS EDS #define HPC_STATUS_FIRE_MASK 2 #define PM_ID_REDUNDANT_MASK 0x00000040 #define PM_ID_NOMINAL_MASK 0x00000020 #define GPI_DATA_REG_ADDR 0x01F800AC typedef UNSIGNEDINT8 HPC_REGS_ACCESS[(sizeof(struct HPC_REGS) / sizeof(MEMADDR))]; /* TSC695F GPI (GENERAL PURPOSE INTERFACE) PORT */ struct HPC_REGS rHPCRegs; /* Local module channel Id. (constant).*/ const UNSIGNEDINT32 HPC_PAR = ACARO_CH2; /* Partner module channel Id. (constant).*/ const UNSIGNEDINT32 HPC_LOC = ACARO_CH1; *ArmFlag = ((TempPattern Service capability #define HPC_STATUS_FIRE_MASK 2 #define PM_ID_REDUNDANT_MASK 0x00000040 #define PM_ID_NOMINAL_MASK 0x00000020 #define GPI_DATA_REG_ADDR 0x01F800AC typedef UNSIGNEDINT8 HPC_REGS_ACCESS[(sizeof(struct HPC_REGS) / sizeof(MEMADDR))]; /* TSC695F GPI (GENERAL PURPOSE INTERFACE) PORT */ struct HPC_REGS rHPCRegs; /* Local module channel Id. (constant).*/ const UNSIGNEDINT32 HPC_PAR = ACARO_CH2; /* Partner module channel Id. (constant).*/ const UNSIGNEDINT32 HPC_LOC = ACARO_CH1; *ArmFlag = ((TempPattern Information to generate DACP Mapping between DACP and DAS Primitives #define HPC_STATUS_FIRE_MASK 2 #define PM_ID_REDUNDANT_MASK 0x00000040 #define PM_ID_NOMINAL_MASK 0x00000020 #define GPI_DATA_REG_ADDR 0x01F800AC typedef UNSIGNEDINT8 HPC_REGS_ACCESS[(sizeof(struct HPC_REGS) / sizeof(MEMADDR))]; /* TSC695F GPI (GENERAL PURPOSE INTERFACE) PORT */ struct HPC_REGS rHPCRegs; /* Local module channel Id. (constant).*/ const UNSIGNEDINT32 HPC_PAR = ACARO_CH2; /* Partner module channel Id. (constant).*/ const UNSIGNEDINT32 HPC_LOC = ACARO_CH1; *ArmFlag = ((TempPattern Information to generate DAP Mapping between DSAP and SubNet Primitives

Behavioural Model Trade-Off A. Driver behaviour “Easy” DVS and DAS SW code generation/translation Solution in-line with today’s philosophy of drivers’ development DACP and DAP algorithms in EDS are good for DVS and DAS simulation EDS might capture a simplified behaviour of the device EDS to be produced by the device user DACP and DAP algorithms in EDS are coded manually B. Device behaviour “Difficult” DVS and DAS SW code generation Manufacturers have to comply to standard rules to describe the device behaviour description/statechart EDS’ device behaviour is good to simulate the device EDS captures the complete behaviour of the device EDS’ device behaviour is provided by the manufacturer DVS and DAS SW code is automatically generated

Algorithms Representation Limitations SCXML & MathML  Baseline, but… Mathematical expressions are not sufficient to represent algorithms including, for example, bitwise operations, checksums, switch cases… State machines are good for the description of macroscopic behaviour or asynchronous events, but not for simple elaborations such as loops or access to arrays. Example from NPAL camera: NPAL_DEFLIST raw data at DAS interface DEFECTIVE_PIXELS_LIST at DVS interface: Each pixel is described by: (uint32 x, uint32 y, uint8 type) Where: pixels (x, y) coordinates are counted from top left, starting with 0 type can be: hot_pixel 0 cold_pixel  1 unknown  2 Bits (little endian) Value 0  cold pixel 1  hot pixel 1-3 Not used 4-13 Pixel column 14-23 Pixel row for(i=0; i<array_size(NPAL_DEFLIST); i++) { DEFECTIVE_PIXELS_LIST[i].type = NPAL_DEFLIST[i] & 0x800000 ? 0:1; DEFECTIVE_PIXELS_LIST[i].x = (NPAL_DEFLIST[i] >> 10) & 0x3FF; DEFECTIVE_PIXELS_LIST[i].y = NPAL_DEFLIST[i] & 0x3FF; }

Algorithms Representation Improvements To incorporate programming language code inside the states of the state machines To complement SCXML and MathML with other formalisms, for example ASN.1 for interface definition and bit fields mapping Additional Needs Availability of parser/code generators Rules and conventions in the way algorithms are hooked to the services SOIS EDS Schema should include the framework for DACP and DAP algorithms definition

Conclusions Objectives Overview of the SOIS EDS study 1 man/year, prototyping of SOIS EDS in Avionics Test Bench Recap on basic SOIS EDS concepts DVS/DAS/SubNet (services), DACP (procedures), DAP (protocols). Points currently under investigation Trade-off between driver and device behavioural model in SOIS EDS Need for the definition of a framework for the algorithms representation in SOIS EDS