ExoMars Rover Vehicle

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3 Page: 3 of 21 TABLE OF CONTENTS 1 INTRODUCTION Purpose and Scope Priority of requirements Guidelines and Traceability DOCUMENTS Normative Documents Informative Documents TERMINOLOGY & SYSTEM DESCRIPTIONS Terms & Definitions Abbreviations Conventions Description of the System SpaceWire Interface Definition Physical Level Exchange Level Network Level Logical Address Use of RMAP RMAP commands supported RMAP command and reply fields Target SpaceWire Address field Target Logical Address field Protocol Identifier Instruction field Key Reply Address field Initiator Logical Address field Transaction Identifier field Extended Address field Address field Data Length field Header CRC field Data field Mask field Data CRC field Reply SpaceWire Address field Status field APPENDIX A: List of TBD's APPENDIX B: List of TBC's LIST OF TABLES Table 4.3-1: Logical Address Allocation Table 5.2-1: RMAP Keys LIST OF FIGURES Figure 3.4-1: Diagram showing Rover data links to the OBC... 9 Figure 3.4-2: Diagram showing nodes in the Rover SpaceWire network Figure 3.4-3: Illustration of Data acquisition request and send to OBC Processor Module... 11

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5 Page: 5 of 21 1 INTRODUCTION 1.1 Purpose and Scope The document contains the requirements for the SpaceWire interfaces between instruments and the On Board Computer. It includes the use of the SpW RMAP protocol and details of the packet contents. This document supersedes the Rover SpaceWire ICD [EXM-RM-RQM-ASU-0041]. 1.2 Priority of requirements The priority of the requirement is indicated by the use of shall or "should as follows: Priority Meaning Description shall Mandatory Mandatory requirements, or hard requirements, which must be implemented. They constitute core requirements of the project in order to fulfil the mission objectives should Goal These requirements are aiming at improving the performances or outcome of the mission. They may be eventually be re-negotiated if their implementation would be demonstrated to be conflicting with the implementation of a mandatory requirement, or overall programmatic constraints. 1.3 Guidelines and Traceability Traceability of these requirements from Rover Level will be maintained using the DOORS system. Requirements within this document are shown in an italic font. Each requirement is preceded by a summary line that contains the following fields, delimited by "/". Doors Requirement Number Intended Verification Method The Doors Requirement Number has the form RV-SPW-xxxx where xxxx is a unique number assigned consecutively. Traceability back to a parent requirement is shown following the DOORS Requirement Number The Intended Verification Method codes are as follows: R - Review - review of design (usually as part of a design review - i.e. reviewing the documentation supplied as part of a datapack). A - Analysis - detailed analysis showing that the equipment satisfies the specified requirement. I - Inspection - visual inspection or a single measurement. e.g. physical feature or a single measurement; mass, dimension verifies that the requirement is satisfied. T - Test - a test or series of tests to demonstrate that the equipment/subsystem meets a performance requirement or survives and/or operates in a particular environment. The requirement text follows the summary line. If tables are considered as part of requirement they are referenced clearly in the text and inserted after and separated from the requirement and are managed as free text attached to the identifier requirement. All document elements not presented in the format explained above are not requirements and will not be verified or tracked.

6 Page: 6 of 21 2 DOCUMENTS 2.1 Normative Documents Normative References are directly applicable in their entirety to this document and are listed below. The applicability is referred to the latest issue available. In case of conflict between a Normative Document and this document the contractor shall inform Astrium for resolution. [NR 01] SpaceWire - Links, nodes, routers and networks ECSS-E-ST-50-12C [NR 02] SpaceWire - Remote memory access protocol ECSS-E-ST-50-52C 2.2 Informative Documents Informative references are applicable to this document only when specifically called up in the text with specific indications of the part of the document that are to be applicable. Otherwise the documents are listed below for information only as an aid for the purpose of understanding. None

7 Page: 7 of 21 3 TERMINOLOGY & SYSTEM DESCRIPTIONS 3.1 Terms & Definitions Instrument This term is used to describe all SpaceWire nodes external to the OBC. This includes payload and platform nodes. NavCam Navigation Stereo Bench Unit, situated on the top of the Mast. Stereo images from this unit are used for generating a DEM of the terrain. LocCam PanCam MicrOmega CLUPI On Board Computer Processor Module Co-Processor Module Navigation Localisation Digital Elevation Map (DEM) Localisation Stereo Bench Unit, mounted on the front of the Rover at the base of the Mast. Stereo images from this unit are used to track the progress of the Rover over a planned path. Panoramic Camera System. An instrument comprising two wide-angle cameras and one high resolution camera. Mounted on the mast. Used to visually characterise the Rover's environment and its geology. Also very important for scientific target selection. Infrared microscope. Used to visually examine the collected sample looking for morphological evidence of life-related processes. Close-up Imager. A robotic replacement for the hand lens. Mounted on the bottom end of the Drill case. Used to visually examine surface rocks at close proximity. Also, to image the fines being produced when drilling. Central control computer of the Rover. It provides the processing platform for Rover control, Payload control and non-volatile data storage. Primary processor of the On Board Computer. The software running on this processor is responsible for all thermal control, power control, data handling and mechanism control. Secondary processor of the On Board Computer. It is dedicated to running processor-intensive image processing algorithms that are used for Navigation and Localisation. Calculation of a DEM from stereo NavCam images of the surrounding terrain and then planning a path to the target destination avoiding any obstacles in the way. Estimation of Rover location and orientation by comparison of successive stereo LocCam images taken whilst moving. Specifies a height (z value) for each ( x, y ) location on a grid. Referred to as 2.5D as overhangs cannot be represented. 3.2 Abbreviations Abbreviation CRC DEM DH DHS EGSE FDIR FIFO FOV HK Meaning Cyclic Redundancy Check Digital Elevation Map Data Handling Data Handling System Electrical Ground Support Equipment Failure Detection, Isolation and Recovery First In First Out Field Of View Housekeeping

8 Page: 8 of 21 Abbreviation HKTM HW (H/W) ICD IR IRD LSB LVDS MSB NR OBC RAM RD RM RMAP ROV or RV SOW SpW SW (S/W) TBC TBD TBW TM/TC Meaning Housekeeping Telemetry HardWare Interface Control Document Informative Reference (Reference Document) Interface Requirement Document Least Significant Bit Low Voltage Differential Signalling Most Significant Bit Normative Reference (Applicable Document) On Board Computer Random Access Memory Reference Document Rover Module Remote Memory Access Protocol (SpW) Rover Statement Of Work SpaceWire SoftWare To Be Confirmed To Be Defined To Be Written TeleMetry /TeleCommand 3.3 Conventions In this document hexadecimal numbers are written with the prefix 0x, for example 0x34 and 0xDF15. Binary numbers are written with the prefix 0b, for example 0b and 0b01. Decimal numbers have no prefix. 3.4 Description of the System The OBC is connected to several instruments (payload cameras and microscopes as well as navigation and localisation camera units). The instruments are connected to the OBC via non-redundant SpW links.

9 Page: 9 of 21 Figure 3.4-1: Diagram showing Rover data links to the OBC whole or in part be reproduced, copied, or communicated to any person without written permission from the owner.

10 Page: 10 of 21 The OBC contains two interconnected SpW routers that connect the Processor Module (PM) and the Co- Processor (CoPM) to each of the SpW equipment. The OBC uses logical addressing. Figure 3.4-2: Diagram showing nodes in the Rover SpaceWire network RMAP write commands are used: by the PM to send configuration and data acquisition commands to instruments. RMAP read commands are used: to read-back configuration data to the OBC Processing Module. to read-back stored acquisition data to the OBC Processing Module. to read-back housekeeping data to the OBC Processing Module. Figure indicates the flow of SpaceWire commands to take an image send the data back to the OBC. It is drawn from the point of view of a single instrument supplier and hence does not show all the instruments. This does not define the architecture of the OBC and does not include redundancy. Any configuration commands that may be required prior to data acquisition commands are not included. Also any commands internal to the OBC are not shown.

11 Page: 11 of 21 Figure 3.4-3: Illustration of Data acquisition request and send to OBC Processor Module

12 Page: 12 of 21 4 SPACEWIRE INTERFACE DEFINITION RV-SPW-468 / ROV-2357 / R All SpaceWire interfaces shall be compliant with [NR 01]. Terminology used in this section is defined in [NR 01]. 4.1 Physical Level RV-SPW-467 / CREATED / T All SpaceWire interfaces shall operate at a data rate of 100 Mbit/s (TBC). RV-SPW-801 / ROV-2357 / R All SpaceWire interfaces shall use 3.3V LVDS transceivers. 4.2 Exchange Level RV-SPW-434 / CREATED / R For each SpW link between OBC and instrument, the transceiver on the instrument shall be set to auto_start mode. Note: The exception is the OBC EGSE link where the OBC transceiver is set to auto_start mode. RV-SPW-435 / CREATED / R For each SpW link between OBC and instrument, the transceiver on the OBC shall be set to link_start mode. Note: The exception is the OBC EGSE link where the EGSE transceiver is set to link_start mode. It is always the OBC that initiates the sending of NULL characters to move the SpW transceiver state machines from Ready to Started. 4.3 Network Level RV-SPW-892 / CREATED / T,R All nodes on the Rover SpaceWire network shall use logical addressing Logical Address RV-SPW-824 / CREATED / T The Logical Address of each node in the Rover SpaceWire network shall be allocated as shown in Table (TBC)

13 Page: 13 of 21 Equipment / Unit Logical Address OBC Initiator Nodes Active PM CoPM OBC EGSE 0x21 0x22 0x24 Platform Target Nodes NavCam Front LocCam Rear LocCam Sun Sensor Spare Router A Spare Router B 0x30 0x33 0x35 0x36 0x39 0x3C Payload Target Nodes PanCam MicrOmega CLUPI LMC 0x41 0x42 0x44 0x46 Table 4.3-1: Logical Address Allocation

14 Page: 14 of 21 5 USE OF RMAP The Remote Memory Access Protocol (RMAP) will be used as the communication protocol on the Rover SpaceWire network. RMAP Write Commands are used for all data acquisition and configuration commands. This includes commands that are not logically memory writes e.g. "Take picture" commands to cameras. RMAP Read Commands are used to read instrument data and, if applicable, configuration and housekeeping data. RV-SPW-925 / CREATED / R All SpaceWire nodes shall be compliant with [NR 02]. 5.1 RMAP commands supported RV-SPW-470 / CREATED / R The SpaceWire interfaces shall support RMAP Write Commands (Logical Addressing) from OBC to instrument. RV-SPW-471 / CREATED / R The SpaceWire interfaces shall support RMAP Write Replies (Logical Addressing) from instrument to the OBC. RV-SPW-474 / CREATED / R The SpaceWire interfaces shall support RMAP Read Commands (Logical addressing) from OBC to instrument. RV-SPW-475 / CREATED / R The SpaceWire interfaces shall support RMAP Read Replies (Logical addressing) from instrument to OBC. 5.2 RMAP command and reply fields This section describes header field usage common to all OBC external SpW interfaces. These header fields are as described in [NR 02] Target SpaceWire Address field RV-SPW-807 / CREATED / T,R The target SpaceWire address field shall have zero bytes as the Rover SpaceWire network uses logical addressing Target Logical Address field The use of the Target Logical Address field is described in [NR 02] Protocol Identifier RV-SPW-484 / CREATED / T The Protocol Identifier shall be set to 0x01 in all cases (indicating RMAP).

15 Page: 15 of Instruction field Packet type field The use of the packet type field is described in [NR 02] Command field Write/Read bit The use of the Write/Read bit is described in [NR 02] Verify bit RV-SPW-512 / CREATED / T Write Commands to the instruments shall support verification (TBC) (verify bit set to '1'). Note: The supplier must identify any constraints when using verification. This bit is only used for RMAP Write Commands Reply bit The use of the Reply bit is described in [NR 02]. Write Command acknowledgements are referred to in [NR 02] as Write replies. RV-SPW-800 / CREATED / T,R All instruments shall provide Write replies when Reply bit is set to '1' Increment bit RV-SPW-715 / CREATED / R The use of the increment bit on all Write Commands and Read Commands to the instruments from the OBC shall be determined by the instrument supplier for each instrument. The only time when an increment bit is set to not increment ('0') is when interfacing to a FIFO Reply Address length field RV-SPW-813 / CREATED / T,R The Reply Address length field shall be set to 0b Key RV-SPW-486 / CREATED / T Keys shall be allocated as shown in Table

16 Page: 16 of 21 Equipment / Unit Key OBC Modules Processor Module (PM) Co-Processor Module (CoPM) OBC EGSE interface 0x11 0x12 0x13 Platform Instruments NavCam Front LocCam Rear LocCam Sun Sensor 0x21 0x22 0x23 0x24 Payload Instruments PanCam MicrOmega CLUPI 0x31 0x32 0x33 Table 5.2-1: RMAP Keys Any Nominal / Redundant instances of a given function have the same key. Distinct keys are intended to detect routing errors particularly when multi-stage routing is required, which is not the case here. It is also less useful when no write acknowledgement is requested. They are included here to comply with the RMAP protocol Reply Address field RV-SPW-818 / CREATED / T,R The target Reply Address field shall have zero bytes as the Rover SpaceWire network uses logical addressing Initiator Logical Address field The Initiator Logical Address field will be set by one of the initiator nodes and the value of the field will be one of those specified in the OBC Initiator Nodes section of Table Transaction Identifier field The transaction identifier is only useful when a reply is requested, since this reply will then contain the same transaction identifier and can be identified by the initiator Extended Address field Extended memory addresses may be requested by the instrument supplier Address field RV-SPW-916 / CREATED / R The range of memory addresses that can be addressed in a RMAP Write Command or RMAP Read Command shall be defined by the instrument supplier.

17 Page: 17 of Data Length field The Data Length field will be specific to each instrument and will depend on the requirements of each instrument Header CRC field The use of the Header CRC field is described in [NR 02] Data field The format of the data field will be specific to each instrument and will depend on the requirements of each instrument Mask field The Mask field and the RMAP Read-Modify-Write Command are not used on the Rover SpaceWire network Data CRC field The use of the Data CRC field is described in [NR 02] Reply SpaceWire Address field RV-SPW-922 / CREATED / T,R The Reply SpaceWire Address field shall have zero bytes as the Rover SpaceWire network uses logical addressing Status field The use of the Status field is described in [NR 02].

18 Page: 18 of 21 6 APPENDIX A: LIST OF TBD'S There are no TBD s.

19 Page: 19 of 21 7 APPENDIX B: LIST OF TBC'S TBC-01 TBC-02 TBC-03 RV-SPW-467 RV-SPW-512 RV-SPW-824

20 Page: 20 of 21 Requirement/Section Cross Reference Page numbers are the pages where the sections start RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW RV-SPW

21 Page: 21 of 21 DOCUMENT CHANGE DETAILS ISSUE CHANGE AUTHORITY CLASS RELEVANT INFORMATION/INSTRUCTIONS A First Issue B Updates to logical address allocations DISTRIBUTION LIST INTERNAL EXTERNAL ASU: Rover Team TAS-I: P. Fissore (Configuration Management) F. Ravera P. Elia Configuration Management Library ESA: M. Clissold (Configuration Management) P. Baglioni A. Winton Astrium Ltd owns the copyright of this document which is supplied in confidence and which shall not be used for any purpose other than that for which it is supplied and shall not in