Hello, Monday, January 26, 2009, 14:14:54, David wrote:
D> I think I've seen seven Agilent 54132A counters and three of units flagged a D> ROM fault after Power On Self Test. They had all been well looked after, D> sitting in racks in a very high end environment, I suspect they were D> switched on continuously all year. The last statement may be a clue of D> course. When I worked with older CNC equipment (Fanuc, Bosch), after any occurence of checksum error we do a total refresh of all EPROMs in a unit. And the same was scheduled to each other routine yearly maintenance (i.e. we reprogrammed all EPROMs each 2 years just to be completely sure). Needless to say, that we had images of any and all EPROM chip archived. D> I did have a very brief play with the 'faulty' ones and things seemed to D> work after the fault message was acknowledged, I could not see any symptoms D> other than the self test error message. A nice counter but I'm D> getting ever more nervous about the ability of current test D> equipment to survive 5 to 10 years. I always try to keep known good images of all programmable chips from equipment I own, if it is possible.. It is already saved me from troubles with my Marconi 2955, where calibration EEPROM (Xicor X2816) failed one day... At the same time, I'm little nervous, too, about more modern equipment that have both firmware and calibration data on a single SMT flash chip. Or, that is even worse, on a some 1.8" HDD... A friend of mine already have Rohde & Schwarz cell phone tester with failed HDD, so internal harddrives is also on my "must be backed up" list now. OS/Firmware usually may be copied from similar unit, but calibration data is something unique and may be very expensive thing to recover. I already saved few various units with leaked EPROMs or parallel EEPROMs using method that I described earlier in this list, but I'm not so sure that it will work equally well with flash chips, so looks like it is better to have a full image on disk. -- Best regards, Yuri mailto:y...@ostry.ru _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.