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SECCHI Flight Software Dennis Wang 202-404-1401 SECCHI Consortium Meeting July 2001 - RAL CPU Utilization Memory Usage VxWorks H/W.

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Presentation on theme: "SECCHI Flight Software Dennis Wang 202-404-1401 SECCHI Consortium Meeting July 2001 - RAL CPU Utilization Memory Usage VxWorks H/W."— Presentation transcript:

1 SECCHI Flight Software Dennis Wang 202-404-1401 SECCHI Consortium Meeting July 2001 - RAL CPU Utilization Memory Usage VxWorks H/W Interfaces S/W Reuse and Upgrades S/W Requirements Current Activities

2 RAD 750 240 MIPS, 133 MHz clock speed, 33 MHz CPCI Bus speed, PowerPC = 10 W 166 MHz version may be available Clock speed can be reduced to save power 60 MIPS, 33 MHz clock = 6.1 W Sleep modes with rapid wake can also be used to save power

3 LASCO CPU Utilization LASCO used 0.6 MIPS for 15 kbits/s LASCO Used 1 MIPS for control of heaters, mechs and housekeeping functions LASCO used 0.8 MIPS for Image Processing

4 CPU Utilization Image processing and compression for COR1, COR2, EUVI, HI-1 and HI-2 scales with the ratio of STEREO/LASCO TM Guide scope and Space Weather equal to 1 MIP HI requires additional processing for cosmic ray scrubbing and summing of images HI-1 cadence is 222 images/hr HI-2 cadence is 56 images/hr

5 CPU Operations PCI Memory get/copy 1 pixel/33 MHZ clock Add, compare, subtract (2 clocks @ 133MHz) Multiply, Divide (20 clocks @ 133 MHz) Processor pipeline typically gets >1 operations/clock

6 HI Image Processing Bias subtraction – 1 subtract, 1 get/copy 2 Image Cosmic Ray Scrub – 2 compare, 1 get/copy 3 Image Cosmic Ray Scrub – 3 compare, 1 get/copy Summing – 1 add/sub, 1 get/copy

7 CPU Utilization TaskMIPSMIPS + 15% C&DH2.242.58 HK11.15 Guide Scope11.15 Image Processing3.594.13 HI (3 Image CR Scrub) 25.929.79 Total33.738.8

8 Memory Usage

9 Memory Map Buffers for each instrument allow rapid image taking for PB and B images for COR 1 and COR 2, EUVI color sequence Near independent timeline for each instrument – no sharing of image buffers Only CCD readout needs to be managed Important for HI-1 and HI-2

10 Memory and CPU Tradeoffs Additional memory is used to increase image cadence for short periods (TM Buffer) or to take and store interesting images (CME detect buffer) Additional MIPS used for additional image processing beyond what was done for LASCO e.g. JPEG 2000, MPEG movies, CME detection

11 VxWorks Real-Time multitasking operating system used for SMEX, Triana, SXI and others C or C++ Code size for Triana ~800kB, SXI ~ 500kB SECCHI should be ~1 MB SXI code heritage for mechanisms and heaters, housekeeping, LASCO – Image Acquisition and Processing

12 Triana ? Hammers Co. has Triana code on PowerPC 750 and will have code on RAD750 by the end of the year Familiarity with Triana S/C code and docs Infrastructure routines such as VxWorks, EEPROM, watchdog should be 100% applicable Other routines may be applicable (messaging, task management)

13 H/W Interfaces MIL-STD 1553 to spacecraft for HK and SC TM – 40-80 kbits/s SCI TM (SWIFT) IEEE 1355 High Speed Serial Camera Interface (similar to SWIFT 1355) RS-422 to HI/SCIP Mechanism Electronics HK board to photodiodes of Guide Telescope


15 VxWorks and SXI Software Fixed priority task scheduling Multiple task threads Interrupt control and vector setup Intertask communications using message queues, signals and semaphores SXI uses message queues for intertask communications


17 SECCHI Upgrades Scheduling and timeline, schedule macros Multiple SECCHI instruments vs single SXI telescope Observing programs Image Processing Image Compression

18 S/W Req – Instruments Observing programs handle complete observation acquisition Normal, dark, cal lamps, EUVI color sequence, polarizer sequence, continuous readout HI image acquisition and summing 2048x2048 pixels @ 1 or 2 (dual port CCD) Mpixels/s Observations synced to 1 sec UTC (0.5 sec requirement/spacecraft)

19 S/W Req - Command S/W Modular design for uplink - 100kB/day Bit packed command sequences Table driven camera setup and image proc. On-board schedule sequences and default observing sequence Real-time commanding for diagnostics and I&T

20 S/W Req – Schedule & Ops Independent operation of each telescope’s mechanisms and lamps Scheduled camera readout (1 HI camera and 1 SCIP camera simultaneously) Schedule items can be modified/deleted Schedule is based on daily uplink Schedule is to be repeated if no ground contact or default sequence

21 S/W Req – Data Handling Image compression lossless (Rice) and lossy (H-compress, SQRT, divide by 2) ROI, occulter and F.O.V masks Diagnostics (Test, None, Debug, Header) Summing and Cosmic Ray Scrub for HI Space Weather channel – JPEG Data Volume = 3.5 –7 Gbits/day/spacecraft

22 S/W Req - Spacecraft Time Sync Message 1 per sec to 1/256 sec resolution with additional 64 microsec offsets Status Bits - Fine pointing, thruster firing, power off warning Watchdog Guide Telescope attitude data for ACS Dual SSR partitions (overwrite or block when full) – priority of downlink ?

23 Software Development Plan Software Code Management (SCCS) and problem reporting and tracking software (GNATS or Teamwork) will be used to control the code, documentation and data Snapshots of each build Software Reviews will be used to validate requirements and design Software Tests with well defined criteria for success will verify quality

24 S/W Schedule 5/16/01 S/W, Ops, Data Sys Peer Review 6/01/01 Flight Software Req Draft 1 7/23/01 Flight Software Req Draft 2 1/15/02 Build 1 – low level infrastructure 5/31/02 Build 2 – driver level tests 7/01/02 MOC-S/C Simulator Tests

25 Recent Activities Software Development and GSE Lab Setup Test setup for working with flight and non- flight hardware – commercial RAD750 4links Space Wire tests Software Requirements Draft 2 release Software Development Plan Study SXI and Triana flight software

26 SECCHI Software Lab (NRL)


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