Re: Working with secondary addresses
dave penkler <[email protected]> Wed, 25 Mar 2026 22:02:52 +0100
| Newsgroups | gmane.linux.hardware.gpib.general |
|---|---|
| Message-ID | <CAL=kjP1P_EwEVKNsYV3WU9+uYay6jHJevoO6=mf3Ownvy8SPtQ@mail.gmail.com> |
--===============1769270951880957699== Content-Type: multipart/alternative; boundary="000000000000125f5f064ddf983d" --000000000000125f5f064ddf983d Content-Type: text/plain; charset="UTF-8" OK, I'll look into it. On Wed, 25 Mar 2026 at 16:35, John via Linux-gpib-general < [email protected]> wrote: > > On 25/03/2026 10:28, dave penkler wrote: > > > > On Wed, 25 Mar 2026 at 01:12, John <[email protected]> wrote: > >> >> I get the following error: >> >> $ ./test_storage.py >> Traceback (most recent call last): >> File "/home/johnc/Test/linux-gpib/./test_storage.py", line 27, in >> <module> >> gpib.write(cmd_find, b'\x31\x0D') >> ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^ >> gpib.GpibError: write() failed: You have attempted to write data or >> command bytes, but there are no listeners currently addressed. >> >> The script uses the same technique that worked in Perl so not sure what I >> am doing wrong at this point: >> > > Your code looks fine. This is not a python issue, it is hardware related. > The problem with the device you are talking to is in one or more of: > 1) Not plugged into the bus > 2) Not powered on > 3) Device is hung > cheers, > -Dave > > > _______________________________________________ > Linux-gpib-general mailing [email protected]://lists.sourceforge.net/lists/listinfo/linux-gpib-general > > > 1) Not plugged into the bus > > The device is plugged in and the Perl script works so its not connectivity. > > 2) Not powered on > > Again, the Perl script works on the same device. > > 3) Device is hung > > There is no change after power cycling the device and computer. > > I am fairly certain its a software issue, but would need to dig into the > library code and maybe attach a logic analyser to understand what's > happening behind the scenes so to speak. > > What does it mean by "but there are no listeners currently addressed." ? > The gpib.dev() addressing command is presumably opening a listen or talk > communication handle? > > Could be an issue with how the device is responding I suppose, but why > would Perl work and Python not when its supposedly doing the same thing? > > I do at least have the option to run with Perl for now, but it would be > nice to have Python. > > _______________________________________________ > Linux-gpib-general mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/linux-gpib-general > --000000000000125f5f064ddf983d Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable <div dir=3D"ltr">OK,<div>I'll look=C2=A0into it.</div><div><br></div></= div><br><div class=3D"gmail_quote gmail_quote_container"><div dir=3D"ltr" c= lass=3D"gmail_attr">On Wed, 25 Mar 2026 at 16:35, John via Linux-gpib-gener= al <<a href=3D"mailto:[email protected]">linux-gp= [email protected]</a>> wrote:<br></div><blockquote class= =3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8ex;border-left:1px solid rg= b(204,204,204);padding-left:1ex"><u></u> =20 =20 =20 <div> <p><br> </p> <div>On 25/03/2026 10:28, dave penkler wrote:<br> </div> <blockquote type=3D"cite"> =20 <div dir=3D"ltr"> <div dir=3D"ltr"><br> </div> <br> <div class=3D"gmail_quote"> <div dir=3D"ltr" class=3D"gmail_attr">On Wed, 25 Mar 2026 at 01:12, John <<a href=3D"mailto:[email protected]" tar= get=3D"_blank">[email protected]</a>> wrote:<br> </div> <blockquote class=3D"gmail_quote" style=3D"margin:0px 0px 0px 0.8= ex;border-left:1px solid rgb(204,204,204);padding-left:1ex"> <div> <p><br> </p> <p>I get the following error:</p> <p>$ ./test_storage.py<br> Traceback (most recent call last):<br> =C2=A0 File "/home/johnc/Test/linux-gpib/./test_storag= e.py", line 27, in <module><br> =C2=A0 =C2=A0 gpib.write(cmd_find, b'\x31\x0D')<br> =C2=A0 =C2=A0 ~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^<br> gpib.GpibError: write() failed: You have attempted to write data or command bytes, but there are no listeners currently addressed.<br> <br> </p> <p>The script uses the same technique that worked in Perl so not sure what I am doing wrong at this point:</p> </div> </blockquote> <div><br> </div> <div>Your code looks fine. This is not a python issue, it is hardware related. The problem with the device you are talking to is in one or more of:</div> <div>1) Not plugged into the bus</div> <div>2) Not powered on</div> <div>3) Device is hung</div> <div>cheers,</div> <div>-Dave</div> </div> </div> <br> <fieldset></fieldset> <br> <fieldset></fieldset> <pre>_______________________________________________ Linux-gpib-general mailing list <a href=3D"mailto:[email protected]" target=3D"_blan= k">[email protected]</a> <a href=3D"https://lists.sourceforge.net/lists/listinfo/linux-gpib-general"= target=3D"_blank">https://lists.sourceforge.net/lists/listinfo/linux-gpib-= general</a></pre> </blockquote> <p><br> </p> <div>1) Not plugged into the bus</div> <div><br> </div> <div>The device is plugged in and the Perl script works so its not connectivity.</div> <div><br> </div> <div> <div>2) Not powered on</div> <div><br> </div> <div>Again, the Perl script works on the same device.</div> <div><br> </div> <div> <div>3) Device is hung</div> <div><br> </div> <div>There is no change after power cycling the device and computer.</div> <div><br> </div> <div>I am fairly certain its a software issue, but would need to dig into the library code and maybe attach a logic analyser to understand what's happening behind the scenes so to speak.</d= iv> <div><br> </div> What does it mean by "but there are no listeners currently addressed." ?</div> </div> <div>The <a href=3D"http://gpib.dev" target=3D"_blank">gpib.dev</a>() a= ddressing command is presumably opening a listen or talk communication handle?</div> <p>Could be an issue with how the device is responding I suppose, but why would Perl work and Python not when its supposedly doing the same thing?</p> <p>I do at least have the option to run with Perl for now, but it would be nice to have Python.</p> <blockquote type=3D"cite"> <pre></pre> </blockquote> </div> _______________________________________________<br> Linux-gpib-general mailing list<br> <a href=3D"mailto:[email protected]" target=3D"_blan= k">[email protected]</a><br> <a href=3D"https://lists.sourceforge.net/lists/listinfo/linux-gpib-general"= rel=3D"noreferrer" target=3D"_blank">https://lists.sourceforge.net/lists/l= istinfo/linux-gpib-general</a><br> </blockquote></div> --000000000000125f5f064ddf983d-- --===============1769270951880957699== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline --===============1769270951880957699== Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Content-Disposition: inline _______________________________________________ Linux-gpib-general mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/linux-gpib-general --===============1769270951880957699==--