Free HP3478A multimeter control program.

[lmester]

I bought a HP3478A multimeter about a year ago. It's a nice meter except for the no backlight LCD display. My old eyes have a problem reading it. I decided to fix this with a Microsoft Windows program to control the meter. You get a big easy to read display on your PC plus the ability to log data and load preset configs into the meter. The program uses a Prologix GPIB adapter to connect to the meter. A Prologix adaper or clone is required.


You can download it from my web server: http://mesterhome.com/gpibsw/

[lmester]

No more HP3478A dead battery anxiety!

Thanks to some info that I found on this board, I've now added an option to backup and restore the meter calibration data. You no longer need to worry about losing the meter calibration data because of a dead battery!

This is a Windows program. It requires a Prologix (or compatible) GPIB adapter.

Even if you don't need to log data or control the meter using your computer, you may want to use this program just to back up your calibration data.

My program performs a checksum on the cal data when performing a read or write. Also, a write verify.

I decided that I couldn't publish this software without a thorough test.  I risked wiping my meter cal to verifiy that the program can properly read and write the cal data.

I turned on the cal enable switch to fully test the code. I edited the saved cal file to create bad checksums and then wrote it back to the meter. I then verified that the meter showed a calibration fail. Next, I wrote the good cal file back to the meter.  The meter was now showing good calibration.

Even with this testing, I would suggest that you should not try to write your meter's calibration unless it's really necessary.

Also, You can do a safe (but not complete) test by doing a read and then a write with the cal switch disabled. The cal switch is a hardware write protect. Software can't override it. If the read and write match, the program will report no errors.

If there are no errors, the software and GPIB interface are working properly.

Finally, if you use an NI VISA USB to GPIB adapter there is backup software available in this thread.

https://www.eevblog.com/forum/repair/hp-3478a-how-to-readwrite-cal-sram/msg1177575/#msg1177575

That's where I found the info needed to port this into my code.

[cellularmitosis]

Fantastic!  I added a link to your software from my meter comparison page.  https://github.com/USACalClub/gear/blob/master/dmms/README.md

[mdijkens]

Nice 

Fantastic!  I added a link to your software from my meter comparison page.  https://github.com/USACalClub/gear/blob/master/dmms/README.md

If you like, you can add my Fluke 45 software also: mdFluke software
(might also work with other Flukes)

[cellularmitosis]

Nice 

Fantastic!  I added a link to your software from my meter comparison page.  https://github.com/USACalClub/gear/blob/master/dmms/README.md

If you like, you can add my Fluke 45 software also: mdFluke software
(might also work with other Flukes)

done!

[rhb]

Made my day.  I just bought a 3478A on eBay yesterday.

[sundance]

Same here!
Thank you so much for sharing this excellent program.
Just got my 3478A last week and was glad to be able to download the cal data and verify that it's valid.
You really made (not just) my day!

-joe

[lmester]

I have put up a new version of the program. I found a bug that would intermittently give a warning that the calibration data write had failed even though it was actually successful. If you have saved cal data with the old version you don't need to re-save it. The cal data file is valid. The write verify had a  bug.

I was performing a verify on the first cal RAM location. This does not actually contain cal data. It's used by the meter as a write protect test. When cal is enabled the meter will periodically write a new value to this location. My updated code now ignores changes in this location.

There are also a few other minor fixes and updates to the program.

New version released on 07-20-2018 https://mesterhome.com/gpibsw/index.html

Also, some users have had problems getting a connection using an Arduino based Prologix clone with the Girlando software.
http://egirland.blogspot.com/2014/03/arduino-uno-as-usb-to-gpib-controller.html
I have ordered an Ardiuno board so that I can do some testing using that adapter.

Are you using an Arduino based GPIB adapter? Do you have any problems? Please let me know your results.

I think it's worth some effort to get my software working reliably with the Arduino adapter. It's probably the cheapest way to make a GPIB adapter.

[coromonadalix]

thanks for the update, nice soft

[TERRA Operative]

Cool, I have one of these meters I am fixing up as my 'beater' meter when I don't want to risk the 34461A on a dodgy circuit.

Will your software work with an official GPIB-USB adapter or the Ebay clones thereof?

[Miti]

If you want back light, look here:

https://www.eevblog.com/forum/testgear/hp3478a-backlight-my-version/msg1505830/#msg1505830

[lmester]

Cool, I have one of these meters I am fixing up as my 'beater' meter when I don't want to risk the 34461A on a dodgy circuit.

Will your software work with an official GPIB-USB adapter or the Ebay clones thereof?

I normally use it with an official Prologix adapter. Note that this software does not work with NI-VISA type adapters. Only adapters that support the Prologix command set.  It's been used with various Prologix clones with mixed results. See my web page for more info.

[cat87]

Thanks for the SW, lmester. Fantastic job. Just tried it with Girlando's  Arduino GPIB and it works a treat. Just had to modify the Version ID that the UI is expecting and that was pretty much it (Settings -> Default Settings)

I was really worried for some time now, that the battery in my 3478 would die on me. Well, not any more.   

[HighVoltage]

Nice looking software !
May be one day to can also make it work on the 34401A? How cool would that be !

[Miti]

Hi lmester,

I just tested this software with the USB to GPIB adapter made by Steven Casagrande, link below and, as expected, it doesn't work. How hard would it be to add this adapter to the list?
https://hackaday.com/2014/05/09/gpib-to-usb-with-a-python-api/

Edit: Never mind, it works. Thanks a lot ! 
Edit1: For some reason, even though I can see the readings from the instrument and (sometimes) I can control it, the message is "Instrument comm fail. Check GPIB port setting". It also cannot read calibration. Could it be because the GPIB adapter requires 460800 baud rate? In the "Default settings" it doesn't accept it but if I set it by hand in the config file, it doesn't complain.

[coromonadalix]

the usb gpib adapter is now an rev 4  from galvant industries

http://www.galvant.ca/#!/store/gpibusb

and the github  infos  FW  etc ...
https://github.com/Galvant/gpibusb-firmware

[lmester]

Hi lmester,

I just tested this software with the USB to GPIB adapter made by Steven Casagrande, link below and, as expected, it doesn't work. How hard would it be to add this adapter to the list?
https://hackaday.com/2014/05/09/gpib-to-usb-with-a-python-api/

Edit: Never mind, it works. Thanks a lot ! 
Edit1: For some reason, even though I can see the readings from the instrument and (sometimes) I can control it, the message is "Instrument comm fail. Check GPIB port setting". It also cannot read calibration. Could it be because the GPIB adapter requires 460800 baud rate? In the "Default settings" it doesn't accept it but if I set it by hand in the config file, it doesn't complain.

Miti,

I've uploaded a new version of the program. It now allows higher baud rates. This was a bug in my baud rate range check. Editing the config file to update the baud rate should not cause problems. That baud rate is valid. My range check just didn't allow it. There are no range checks for data loaded from the config file.

Since you know how to edit the config file, there are two more "hidden" settings that you can select.

Set line 20 to 1 to turn on debug messages. You could copy the contents of the Instrument status window and send it to me.

More important, some Prologix clones require a delay between commands.

Line 27 sets this delay. The default is 0. The units are milliseconds. Try 100 - 500. Very large values can effectively "hang" the program. It's actually running, but, all of those time delays add up to the point where nothing is happening.

Here is a link to the config file settings: https://mesterhome.com/gpibsw/hp3478a/Software/ConfigFile.txt

[Miti]

Thanks lmester!

The baud rate works but comm still fails with delays up to 500ms. See attached.

[lmester]

Thanks lmester!

The baud rate works but comm still fails with delays up to 500ms. See attached.

Miti,
Instrument detection is failing. I don't have your Prologix clone adapter available for testing. Debugging this could require many messages and file transfers between us to resolve the problem. We should switch this conversation to private messages or email. No need to fill up this thread with messages that would be of no interest to most readers.

I'll send you a PM.

[steve1515]

Hi lmester.

I just got the same adapter that Miti has and am also having issues. It seems to not be able to read the result of the "S" command even though I can when I use a terminal program. Were you ever able to figure this out?

Here's my debug log... Any tips?

Code: [Select]

Version 03/23/19
Windows 7 / S-2008 R2 Service Pack 1 Platform ID 2
Config file loaded.
Debug ON.
Command delay = 500ms.
Max COM port = 64.
OC:Open COM5 CheckCom.
CheckCom start COM5
CheckCom end CreateFileA COM5
CheckCom port found
CheckCom end CloseHandle COM5
OC:Open COM5 open port.
OC:Open COM5 OK.
CA:Start CheckAdapter on COM5
CA:Check Prologix GPIB adapter. ProVer =:"Version 5.0"
CA:Found Prologix adapter (No arduino delay).
CA:Exit checkAdapter on COM5
COM port set to COM5
IG:Start InitGPIB
IG:Find Prologix GPIB adapter.
IG:ProVer srch:"Version 5.0"
IG:Found Prologix adapter.
IG:set ++mode 1.
IG:set eot_enable 0.
IG:set read timeout:++read_tmo_ms 3000
IG:SetGPIB Address ++addr 18 success.
IG:set EOI 0.
IG:set EOS 0.
IG:Set auto talk mode off: ++auto 0  success.
IGT:QSB result
IGT:Failed instrument ID: BR$=:""
IGT LEN BR$:0
Instrument comm fail!
Check GPIB port setting!
Check GPIB port setting!


[Miti]

Try Galvant2 from here:

https://mesterhome.com/gpibsw/hp3478a/Software/

[lmester]

Hi lmester.

I just got the same adapter that Miti has and am also having issues. It seems to not be able to read the result of the "S" command even though I can when I use a terminal program. Were you ever able to figure this out?

Here's my debug log... Any tips?

As Miti said, you can try the custom "Galvant" versions on my web site. These are NOT fully functional. The Galvant firmware does not support binary transfers. This causes the calibration load/save to fail.

[steve1515]

Thanks. It works! 

[steve1515]

I've been re-writing the firmware for the Galvant adapter with a goal of full compatibility with the Prologix adapter. I expect to release it soon, since I only have a few things to work out. Hopefully this will make it so lmester doesn't have to keep different versions of his program and also so other people can use the open source hardware just like the Prologix in their other projects. 

In order to get my firmware to work the same as the Prologix, I'll need someone who has one to enter a few commands and send me the PuTTY log for review. I would do this myself, but I don't own a Prologix for testing... but that's why I bought the Galvant hardware. 

Can someone with a Prologix please execute the following commands in the order provided with logging turned on and upload the file? I'm mainly looking to match certain command outputs and line endings for maximum compatibility.

Code: [Select]

++ver
++addr 18
++addr
++addr 18 97
++addr
++eos 1
++eot_char 13
++eot_enable 1
++addr
++ver
++help
++eot_char 10
++addr
++ver
++eos 0
++addr
++eos 2
++addr
++eos 3
++addr
++help

If PuTTY is used on windows, please use the following settings:

Code: [Select]

Session -> Logging -> Session Logging = All Session Output
Terminal -> Implicit CR in every LF = OFF
Terminal -> Implicit LF in every CR = OFF

One final thing I'm wondering...
When the Prologix is connected to the HP 3478A, if "++read" is sent, does the meter return the value continuously or only just a single read?

Thanks for any help anyone can provide!
I hope to publish the source code on GitHub for all to use once it's done.   

[steve1515]

I just wanted to update here that I've released what I call version 6 of the firmware for the Galvant GPIBUSB adapter. This firmware is highly compatible with the Prologix command set. You can find it here: https://github.com/steve1515/gpibusb-firmware

This firmware allows the Galvant adapter to work with the regular version of lmester's HP 3478A control program. Binary read/write works as well, so the meter calibration can be read and written.