> Le 11 août 2016 à 12:15, Martyn Smith <[email protected]> a écrit : > > Hello, > > I have a strange fault on a PRS10. Wondered if anyone had seen it. > > I am running a PRS10 and at the same time monitoring its FC (the frequency > control value) and Status byte data values. > > So normally, the Status shows are all zeros, except 2nd from last is a 1, > showing the unit is not receiving any 1 pps signals. > > What happens is the FC value suddenly jumps from its current setting (-150 > for example) to zero, for no apparent reason.
if -150 is really what you saw, then it is out of bounds as the two values returned by fc? are both +ve. if they go to zero, check the eeprom values fc!? 58,5485,1534,1434 for example If they are reasonable then possible the eeprom is not being read correctly after reset. > > Then a short while later, the Rubidium's status bytles go crazy, mostly to FF. This indicates a microprocessor reset . After a power cycle you can see: st? 255,255,255,243,162,255 ie most FF when you read again you get the current values st? 0,0,0,0,130,0 for example then if you reset the microprocessor RS 1 PRS_10 st? 255,255,255,243,162,255 back to the initial state st? 0,0,0,0,130,0 So it looks like you are getting resets. Possibly from brown outs. Maybe a low power condition at reset prevents eprom data being read correctly. Are the affected RBs on the same power supplies? > > Then the rubidium goes back to the previous correct state (all zeros) but the > FC value is now zero. > > If you do connect a 1 pps, you get the same fault. > > The confusing thing is I've suddenly seen this on 3 or 4 different > rubidium's. Some brand new, some five years old. > > Obviously suspect the power supply, but it doesn't seem to be that. > > Best Regards > > Martyn > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. "The power of accurate observation is commonly called cynicism by those who have not got it. » George Bernard Shaw _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
