210 likes | 313 Views
On-Board Data Handling for the PAMELA Experiment. Ralf Wischnewski Roma2 & DESY-Zeuthen. Alghero, 30.9.2002. The task Space requirements Pamela CPU: PSCU On-board DAQ design Data downlink Status & Summary. The INSTRUMENT. TRD e ± ,p threshold detector.
E N D
On-Board Data Handling for the PAMELA Experiment Ralf Wischnewski Roma2 & DESY-Zeuthen Alghero, 30.9.2002
The task • Space requirements • Pamela CPU: PSCU • On-board DAQ design • Data downlink • Status & Summary R.Wischnewski
The INSTRUMENT TRD • e±,p threshold detector. • 9 radiator planes (Cfibres) + straws tubes (Xe/CO2). • Separazione 102 e/p (E > 1GeV/c). Time-of-flight system • Trigger(Level-1) • TOF particle identification (< 1 GeV/c) • dE/dx • Plastic Scintillators + PMT • Time resolution ~70ps TOF TRD Anticoincidence • Plastic scintillators + PMT • TrackerAccept.+BGSuppres. TRK Si Tracker + Magnet • PermantMagnet B=0.4T • 6 Si-planes (x & y) • Spatial resolution ~3m MDR = 740 GeV/c ANTI PSCU Si-W Calorimetro • Imagining Calorimeter (e/p) • Resolution for e± • E/E = 15% / E1/2 • 22 planes Si-X / W / Si-Y • 16 X0 / 0.6 0 CALO Neutron detector • Energy range extention to 10 TeV (e and p) • 36 3He counters in a polyethylen moderator ND Pamela CPU R.Wischnewski
Real-time response to S/C Telemetry requests • Quasi-autonomous experiment-control: Run / Calib / SetupChanges • Pamela Status Verification and Emergency / Error Response • Logging and optional extended debugging • On-Orit Debug of Soft/Hardware with uplink comands <1 kB/day • needs a highly debugged & automatized system Science Data Acquisition • Trigger rate: 1 Hz – few 10 Hz • Event size: ~5 Kbyte/event • Dead time ~10% i.e. EvtR/O to CPU-MM ~ 10 ms. Experiment Slow Control & Quality Monitoring The Tasks (1) R.Wischnewski
Space Requirements • Space Qualified Systems: • - Radiation hardness (SEU, Latchup) • - Mechanical stability (vibration & shock) • - Thermal stability • Limited: • Power consumption, Mass & Volume • Interface to Satellite CPU • Extended error detection • High redundancy design & ground-test Telemetry (downlink/uplink) The Tasks (2) R.Wischnewski
PAMELA STORAGE AND CONTROL UNIT • CPU (ERC32 SPARC V7) 17 Mips @ 24MHz • SRAM 4 Mbyte • Boot PROM • EEPROM1 Mbyte • 1553 Remote Terminal to Satellite CPU • 64 Kb x 16 RAM buffer • Logic ASIC which include PCMCIA • bus controller & Parallel System Bus • Solid State Mass Memory: 2 + 2 Gbytes • Pamela Interface (PIF): DMA bus controller and TAM interface • Telemetry & Housekeeping board: 32 outputs + 78 inputs • DC/DC converter integrato da 27 V a 14.4 V + 5.2 V • Quartz clock ± 1 ms R.Wischnewski
PAMELA DAQ – Schematics R.Wischnewski
FrontEnd R/O Compress IDAQ MPX,Level-2 Trg PSCU Spacecraft MKCMD, TeleM CPU CPU CMD,Setup CMD,Setup PIF Data,Status Data,Status MassMem >100GB Data MassMem TMTC Trigger 16 x Error PAMELA DAQ – Schematics Detectors R.Wischnewski
Data Downlink to S/C and Earth • Science and HK data (1-2 GB) to be transfered from Pamela to Satellite MassMemory (>100GB) every few hours. • Asynchronous request from Master S/C-CPU. • Downlink from S/C to earth during ground station passages (Moscow & Sturup/Sweden) @ 320Mbps over a few minutes. • Needs fast analysis for uplink response on next orbit. • All operations based on pre-defined absolute time schedule, arbited from S/C and uplinked from Ground. R.Wischnewski
MM S/C Pamela Data Path:S/C to Ground DLink S/C R.Wischnewski
PSCU – Engineering Model RAM (2x2 GB) CPU, PIF, TMTC DCDC The PSCU is constructed in 2 phases by LABEN/Milano: 1. Engineering Model (EM), currently under full test @ INFN 2. Flight Model (FM), under construction @ LABEN R.Wischnewski
PAMELA ENGINEERING MODEL • Assembly of the Engineering Model (EM) is the major functionality and I/F test to be passed before the final Flight Model (FM) is build: • System compability test; • Mechan. & electr. interface test; • Test procedure definiton for ground test equipment (EGSE). Note: The PSCU is (with Power Supply)the main Interface between Pamela and the Satllite. R.Wischnewski
PSCU-EM Tests • Basic functionality test: • Trigger rate 80 Hz • 1/10 evts transfered to CPU-RAM • to simulate sampled event analysis • Telecomand communication • (1553 Bus) • Write to PSCU MassMemory • and download via TAM R.Wischnewski
PSCU TEST EQUIPMENT • Full functionality test of PSCU needs an • “Electrical Ground Support Equipment” (EGSE), • simulating all system interfaces: • power supply (27 V) • Control Command (ON/OFF, RESET) • bus 1553 for telecomands • telemetry • I-DAQ board to receive FE Comands and reply detector data in real time • monitor for PSCU electrical/thermal status • debugger and monitoring SW • simulator for Housekeeping input • event trigger simulation • science data readout (TAM) R.Wischnewski
PSCU TEST EQUIPMENT @ ROMA R.Wischnewski
PSCU - ON-BOARD SOFTWARE • RTEMS as Operation System: • (Real-Time Executive for Multiprocessor systems) • multitasking • preemptive or monotonic scheduling • comunication zone and intertask synchronisation • interrupt handling • optional: task & interrupt priority • dynamic memory allocation • RTEMS is supported by ESA/ESTEC including Cross Compiler ERC32CC with: • GNU C compiler • Linker, assembler, archiver etc. • Standalone C-library • RTEMS real-time kernel with ERC32 BSP • ERC32 boot-prom utility • Standalone simulator ERC32 • GNU debugger with ERC32 simulator & DDD R.Wischnewski
Main Functional Modes and Tasks Overview of Pamela main functional modes and parallel system tasks. Telecomands from S/C Master CPU switch between operation modes. Automatic-mode change is under implementation. TMTC-Housekeeping, S/C 1553 I/F, Logging, Error check and General Interrupt handling tasks are permanentely active. R.Wischnewski
Science data event managment chart R.Wischnewski
BEAM TEST @ CERN SPS 5-12/06/2002 e @ 20-300 GeV p @ 300-350 GeV PSCU Buffers are optimized for event size < 16 kB. Tracker data size (compressed). R.Wischnewski
Second Level Trigger Trigger on IDAQ-Board Fast DSP-rejection algorithm for Background events, w/o PSCU. Using: AntiCoincidence – Veto. But: signal rejection by back- scattering from calorimeter. Calorimeter - particle classification (non-interacting, hadronic, em). TOF - n° of hits per plane TRACKER - n° of clusters, no online reconstruction. Verification with SPS/PS test beam data (2002). R.Wischnewski
PAMELA DAQ - Summary • Most components of the Pamela DAQ and Slow Control are ready for system test. • CPU-EM in full test @ INFN; CPU-FM in production @Laben • Finalization of Pamela Slow & Autonomous Control Procedures • Next steps: • DAQ / FE-board system test with & S/C-Simulator in Rome (12/2002) • Deliver Pamela-EM to Russia for S/C EM test (1/2003) • Integration of Pamela FM with FM-PSCU, physics test, delivery to Russia (5/2003). R.Wischnewski