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From: Phil Hobbs <pcdhSpamMeSenseless@electrooptical.net>
Newsgroups: sci.electronics.design
Subject: Re: GPIB bus topology
Date: Wed, 1 May 2024 22:34:23 -0000 (UTC)
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piglet <erichpwagner@hotmail.com> wrote:
> bitrex <user@example.net> 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?
>> 
> 
> Daisy chain, no more than two connectors per unit as the accumulated weight
> gets problematic.
> 

Not to mention the torque, when someone tugs on a cable. 

I believe that folks have been known to do a star connection, with the
center node being just cables, for that reason.

The interface speed is less than 1 MHz, even when externally clocked, so
it’s all the same electrically. 

Cheers 

Phil Hobbs 

-- 
Dr Philip C D Hobbs  Principal Consultant  ElectroOptical Innovations LLC /
Hobbs ElectroOptics  Optics, Electro-optics, Photonics, Analog Electronics