Re: [Linux-gpib-general] Agilent 82357B repeatable hard failure

[Jim H. <ji...@ov...>]

On 7/27/23 12:13, dave penkler wrote:
> It would be interesting to see if there is any timing difference 
> between the W1 and W4 write / read sequence with the logic analyser.
> You might want to try and run ibterm with the -N option. After sending 
> Wn hit enter again to trigger the read. Perhaps a short delay between 
> the write and read may have an effect.
> /d

Hi Dave, Everyone,

I got the logic analyzer hooked up and the transfers for "W1" and "W4" 
look the same to me.
I'm not sure what to try next.

I'm attaching the captured traces.  gpib4.vcd is the 'W1" command, 
gpib5.vcd is the "W4" command.
These are timing captures from  a HP 16702 analyzer with a 16556 card.  
I'm using an HP 10342B
HP-IB interface probe so this is trusted old school technology.

I have a python script to get the traces and  convert them to .vcd files 
which can be viewed
with GTKwave.

I had the 16556 card sampling at 100ns.  With the 1M sample depth this 
gives me 1/10 of a
second.  I decoded the traces by hand and I can see the "W1" command and 
the "@" response
and the "W4" command and the "F" response in the respective traces.
I might be missing something that happens outside my 1/10 second window 
or a glitch which
I miss by sampling at 10 MHz.

I did the test using ibterm and triggering the analyzer on a falling 
edge of DAV and data == A8
to match the W in the command.

I also tried triggering on the DAV falling edge and doing a "W1" command 
after the "W4".
The analyzer didn't trigger so I assume that the Agilent 82357B won't 
send commands
after the "W4" .

Jim Houston