Path: ...!news.mixmin.net!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: chrisq Newsgroups: sci.electronics.design Subject: Re: GPIB bus topology Date: Sat, 4 May 2024 16:15:21 +0100 Organization: A noiseless patient Spider Lines: 38 Message-ID: References: <6632ba30$0$8096$882e4bbb@reader.netnews.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Sat, 04 May 2024 17:15:21 +0200 (CEST) Injection-Info: dont-email.me; posting-host="8ffd65fa43b498d6ebe0b28e87220339"; logging-data="1303024"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX185xdEfFRKyyDhp2Sf/f2jB" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:lF5VVGxcJNFuBglZT2cAZdcQp7U= Content-Language: en-US In-Reply-To: Bytes: 2850 On 5/2/24 01:42, Don Y wrote: > On 5/1/2024 2:54 PM, bitrex wrote: >> I have several pieces of HP gear (DMM, counter, Agilent-branded >> triple-output supply) I'd like to connect to a National Instruments >> USB to GPIB adapter for some measurements. >> >> IEEE 488 is somewhat before my time and I see that the connectors are >> stackable, is there a preferred bus topology for a few pieces of gear? >> Star, linear/daisy chain with the stack on the interface, linear/daisy >> chain with the stack on the first piece of gear? Does it matter much >> in this use case? > > The bus is dog slow (by today's -- or yesterday's! -- standards) so > topology > isn't that important.  The cables, though, are costly, short and constrain > how you can (re)arrange your kit. > > Consider, instead, GPIB-ethernet adapter(s) as this gives you a lot more > freedom in siting your kit.  I move things around as my benchtop often > doesn't have space for prototype, power supplies, instruments, etc. so > things "come and go" -- even during a session -- as my needs change. > It's nice to only have to worry about a thin network cable (easily > disconnected with one hand, "blind") instead of a frigging "hose"! > Have gpib based test gear all around the lab, beyond the limit of cables, which are clunky and heavy anyway. Solution here was the Prologix lan to hpib adapter, which puts the test gear on the local subnet, where it belongs. Have written an os package to drive it, so that at top level, it's all shell scripts, and Can be built and controlled by any unix with gcc and a shell, even cygwin on windows. Prologix used to be quite low cost, but they have raised the price considerably since, which is a pain, but still lower than the lan / hpib adapters from HP or NI... Chris