> > Does it work, in a loop, to send 3456A commands > > to read voltage, get the response, and then 5370A > > commands to read frequency, and get a response? > > > > /tvb > > Yes, but I've been getting occasional squirrely values from the 3456A in > that mode, possibly because of a timeout and without using the bus > signals there's no way to check whether the instrument has actually > completed. There are code workarounds to that, but I was hoping to use > the "data ready" bit to validate the reading. > > But I think I may have found the problem -- I just ran through the > internal test set, and I'm getting a failure on the RAM test. That > probably explains the SRQ failure, and may even explain why every so > often a reading isn't in the right format. Now I just need to find a > couple of ancient 4118 RAM chips. > > John
I've got an old 3456A and can pull its RAM chips for you if needed. I dug up an old QBASIC program from 1999 where I talked to a 3456A to log mains voltages. See: http://www.leapsecond.com/tools/3456.bas It looks like the controller simply waited for the CR/NL terminated single-line response from the T3 trigger command. T1 or T2 would be trouble, in this case, I think. /tvb _______________________________________________ time-nuts mailing list time-nuts@febo.com https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts