Experimental Physics and
Industrial Control System

[email protected] (Bill Brown) · Fri, 13 Dec 96 13:32:42 PST

> Date: Fri, 13 Dec 1996 14:51:24 -0600
> From: [email protected] (S. Joshua Stein)
> Subject: Re: Serial and GPIB IP's and IP Carriers
> Mime-Version: 1.0

>   We've had some interesting problems with the NI-1014 GPIB board talking to
>   some Hewlett Packard instruments - specifically some of their 'scopes. I spent
>   a good week with a GPIB logic analyzer watching transactions between the
>   NI-1014 board and an HP54615B oscilliscope - it seemed that ocasionally the
>   GPIB board would not honor an assertion of one of the handshaking lines 
>   from the 'scope (I believe it was NRFD) causing all sorts of bad things
>   (garbled messages, locking up the scope, etc).
>   
>   The solution (after talking many times to many engineers at HP and NI) was
>   to use a different controller. I switched to a greenspring IP running on
>   a 162 (with Hideos - see how I tied that in?) and everything has worked great
>   since.

We've had problems with the NI-1014 also - particularly with older instruments
like ion-gage controllers.

We've got a simple hardware hack which seems to do much for their reliabilty.
Essentially, it consists of dividing down the clock to the GPIB controller
chip.  We cut one trace, and add one IC, dead-bug style.  Takes about 20
minutes for a good tech to do.

-bill

Experimental Physics and Industrial Control System

Experimental Physics and
Industrial Control System