Help with 3458A: How to get/save the SRAM data via GPIB

[Timmeee]

Hi there,

I got myself a 3458a from Agilent and opened it recently.
What I saw was quite surprising, the date code on the Dallas SRAM's said,
that there were manufactured in the 2000's (or am I wrong?)

So this one's kept the data for 24 years and the meter can still red from them

I don't want to lose the cal data and played around with my GPIB to USB adapter and the HP3458.exe from the KE5FX toolkit.
But I don't understand/I can't find out where the output is saved (if it was saved), or should I take the output from the command promt?

I haven't tried WinGPIB for now (I will do this later) and hope for an "easy to use File" which I can take to an TL866 or similar.

So as along as I don't have the cal data, the DMM should keep it alive as long as it is turned on?
(so in first step I had it running, cause I had do work)

So could anyone give me some tips, how to collect the Data from the SRAM's properly?

And for my understanding, there are 3 Chips, 2 of them (the 1230's) are holding the cal data and are the important ones and the 1220 is only used for user programming stuff?

Which data (Block?) belong to which position on the Board?
(the WinGPIB creates 2 files, U121 and U122, so these are the part numbers on the PCB I guess?)

And at least: Which kind of replacement would you recommend, replace with new Dallas SRAM's or take some FM18W08 with an adapter PCB?


Big thanks for your support

Tom

[alm]

It's the other way around, U132 (DS1220) is the calibration data that you want to save, and the DS1230s are the user memory that is unimportant and can just be replaced by blank NVRAM. It will complain about RAM checksums on power up, but you can just reset it once via front panel and it will initialize them.

I haven't used the KE5FX toolkit, but according to the documentation you pass it a filename on the command prompt, for example hp3458a-cal-data, and it will then create a file hp3458a-cal-data.hi in the current directory with the contents of the NVRAM. Run hp3458 without any parameters to see more help.

It is also possible to read the DS1220 with an EEPROM programmer after desoldering (see here on some hints on desoldering), but that is more risky so my preference would be to save it via GPIB first. But it wouldn't hurt to read it after desoldering and check if the data is the same.

I'd say replacing the NVRAM by FRAM is the more durable fix. See here for instructions.

[Timmeee]

Ah, okay thanks for the clearance.

I had read header in the cpp file, but I couldn't find the file, that should be created in the directory (I try it again, who knows)
Also outstanding is the variant via WinGPIB from IAN.

I also thought, I could desolder the NV's, but I read that there is a 25% chance to flip some bits in the NV or damage them.
So my way to go would be try out any way via GPIB before that.

Thanks for the Article about the FRAM replacement, this looks doable, and I could forget about future replacements because of a dying NVRAM.

When I'm home, I can tell more.

Thanks.

[IanJ]

I had read header in the cpp file, but I couldn't find the file, that should be created in the directory (I try it again, who knows)
Also outstanding is the variant via WinGPIB from IAN.

Been a while, but I just tried the latest version of WinGPIB and the 3458A Calram read works fine.

As a note, the path that is displayed in the "File(s) saved here:" comes up first and as WinGPIB continues to read the data from teh 3458A. The status should say "DONE!" when completed.

Here's an example of where the files is saved.......my USERNAME being "Ian".
C:\Users\Ian\Documents\WinGPIBdata\3458A_Cal_ram_2024-02-15_14-57-47.bin
I.E., it should be in your \WinGPIBdata folder.
Is your PC set up to hide .bin files, or hide file extensions.......better to see all IMHO.

There was an old issue where the WinGPIBdata folder appeared TWICE on a users PC, this was related to how the app was updated from a previous rev, but this was many, many revs ago.
If you still can't find the .bin file then try searching your entire drive C:, you may find it elsewhere.

In regard to desoldering the DS1220Y then it's easy enough if you are experienced in desoldering THP IC's. Some tips:
- Use a desoldering tool, one of those suction ones. Wiggle the gun as you suck out the solder for a second or two on each pin.
- Never, ever try and 'force' the IC out if it's 'stuck' after desoldering, you'll only end up ripping the through hole plating from the board. Not a total disaster but very inconvinient.
- As mentioned below......try everything to read the GPIB data first......thats your lifeline.

Ian.

[Timmeee]

Hi there,

finally I could read out the Cal Data (I guess? file down below).

But I can't open WinGPIB, in the installation version, the program doesn't start, and the Mobile version does start but is throwing an Error (also see below)

Does WinGPIB work with a Proligix adapter?
(Not original)

A friend of mine had an ersa X-Tool Vario, this in combination with a short period of heating with not too much temperature should work, thanks for the tips

I've bought the 3 FRAM Boards (I'm also thinking about an upgrade to opt 001) and as soon as these arrive, I will change them.

[IanJ]

There is no mobile version.
If you have never installed WinGPIB before the you need the FULL install.
The other zip is just a simple way to update/replace the EXE without running the full install again when I publish a new version.
If the full version is not installing then if you can provide more info I can help, or see post #1 on the WinGPIB thread.

If you look through the WinGPIB thread here on the forum I think there is info there about prologix.

Ian.

[Timmeee]

I forgot to add the MCP2221DLL-M-dotNet4 to the installation folder, so I'm clearly to blame 

When I want to use the COM Port (Prologix) how can I set it up?
(haven't found any detailed info's about that)

Thanks for your help!

Tom

[IanJ]

I forgot to add the MCP2221DLL-M-dotNet4 to the installation folder, so I'm clearly to blame 

When I want to use the COM Port (Prologix) how can I set it up?
(haven't found any detailed info's about that)

Thanks for your help!

Tom

If you are connecting to a serial COM port you need to set something like:
COM4:115200,N,8,1,CRLF
(COMport,baud,parity,databits,stopbits [,newline])

See the GPIBchannels text file as it has lots of examples of various ways of configuring the interface.

See also:
https://www.eevblog.com/forum/metrology/3458a-logging-via-windows-app-revisited/msg4199353/?topicseen#msg4199353

Ian.