1、Lessons Learned Entry: 1331Lesson Info:a71 Lesson Number: 1331a71 Lesson Date: 2002-11-27a71 Submitting Organization: GRCa71 Submitted by: Michael DohertySubject: Critical Testing of Computer Systems Hardware During Buildup Description of Driving Event: The Physics of Colloids in Space (PCS) experim
2、ent was launched on ISS Flight 6A in April 2001, was activated in EXPRESS Rack 2 on May 31, 2001, and was successfully operated on the International Space Station (ISS) until February 24, 2002. On February 24, 2002, at the onset of a scheduled operational run on ISS, the PCS flight system computer (
3、within the PCS Avionics Section) failed to boot up. On-orbit recovery efforts were undertaken but were unsuccessful. The Avionics Section was removed and brought back on ISS Flight UF-2.Lesson(s) Learned: For computer systems which boot from parameters stored in CMOS (i.e., battery-backed Random Acc
4、ess Memory), the complete set of BIOS parameters may not get fully restored upon system detection of CMOS corruption.Recommendation(s): The response to this lesson is to perform CMOS corruption testing during the hardware development phase to determine the systems ability upon detection of corruptio
5、n to restore all values necessary for boot-up.Evidence of Recurrence Control Effectiveness: CMOS corruption testing was successfully conducted on PCS once the hardware corrections were made.Documents Related to Lesson: Provided by IHSNot for ResaleNo reproduction or networking permitted without lice
6、nse from IHS-,-,-N/AMission Directorate(s): a71 Exploration Systemsa71 Aeronautics ResearchAdditional Key Phrase(s): a71 Computersa71 Flight Equipmenta71 Flight Operationsa71 Hardwarea71 Payloadsa71 Safety & Mission Assurancea71 SoftwareAdditional Info: Approval Info: a71 Approval Date: 2003-04-07a71 Approval Name: Jim Cerya71 Approval Organization: GRCa71 Approval Phone Number: 216-433-3002Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-
