[time-nuts] Off the wall: anyone withexperienceprogrammingHP3456A?

Poul-Henning Kamp phk at phk.freebsd.dk
Sat Sep 10 17:13:18 EDT 2005


In message <PKEGJHPHLLBACEOICCBJMEEAEIAA.jmiles at pop.net>, "John Miles" writes:

>Hmm.  From what I can tell via Google, the rule is that you're supposed to
>have two-thirds of the devices on the GPIB bus powered on.  Good to know,
>even though most of the devices I have don't seem to enforce this guideline.

It couldn't possibly enforce it, how do you tell the difference
between two cables being connected and two cables meeting at a
powered down instrument ?

>I'll refrain from editorializing on the wisdom of designing an interconnect
>bus with a rule like that, as foaming-at-the-mouth howling rants are OT for
>the time-nuts list.

You know, back when it was produced, the HP-IB was a pretty good
sized improvement over random (and I mean *RANDOM*)
ttl-bcd-with-some-extra-lines kind of instrument interfaces that
existed.

It also wasn't anticipated that people would cable it up without
using it: it was mostly intended for use with instruments that
saw so intense use that computer control could be afforded.

So you can't really blame the designers back then for not imagining
the future existence of self proclaimed nuts owning a few millions
worth of HP kit which they don't power up unless they need it...

fair is fair :-)

-- 
Poul-Henning Kamp       | UNIX since Zilog Zeus 3.20
phk at FreeBSD.ORG         | TCP/IP since RFC 956
FreeBSD committer       | BSD since 4.3-tahoe    
Never attribute to malice what can adequately be explained by incompetence.




More information about the time-nuts mailing list