HP3458A(Agilent) will not respond to any read/query command - Page 1
Forum section: electronics / general

author: Mikhail_K
author_rank: Contributor
timestamp: June 19, 2023, 03:46:06 pm
content: Please help! It is for the third day I'm hopelessly trying to receive the data from my 3458A. It is the second one, so I was about to just use the vi's created for the old one. I use LabView Home and NI USB-GPIB. I tried END ON, END ALWAYS, PRESET NORM but to no avail! The device will receive and execute all commands, but any reading (except for the system Read Status Byte from VISA Test Panel -not *STB? query which doesn't work) fails. I checked the physical level - no issues. The A5 board components are dated year 2006.Whether I type in ID? or *ID? I receive an error communicated through GPIB - notorious iberr = EABO. On the front display I see error "103, SYNTAX -- * Expected command header."If I try just Read button on the NI-488.2 Communicator - I get no error on the device, but the same bier = EABO through the GPIB. (My working 3458A replies with the last measurements to this Read).What else I can check or configure?

author: Kleinstein
author_rank: Super Contributor
timestamp: June 19, 2023, 04:50:18 pm
content: The error message suggests that the data transfer to the meter is not working OK. The GPIB interface is parallel and there could be a hardware problem (as simple as a bad contacts / bad pull up) with one of the lines. Many of the older meter supported a talk only mode that could be tested. Another point to check could be having 2 meters on the same bus and check if the bus is still working with the other meter. So stuck bits would also disturb other units on the bus.A point that may be wrong is the end of line setting ( CR vs CR LF etc.).

author: IanJ
author_rank: Unknown
timestamp: June 19, 2023, 04:57:04 pm
content: Sounds like one of the two GPIB IC's is faulty. It's connecting but you're not getting much in the way of data transfer.U905 & U906.I've had similar/same with other HP DMM's.Subject to the connector pins etc being intact etc.Ian.

author: Mikhail_K
author_rank: Contributor
timestamp: June 19, 2023, 05:15:14 pm
content: 3458 supports talk only by changing its address to 31. Then it will submit data to GPIB printer which I apparently don't have. How to receive the data on a PC I can't get. They say6 the actual glib remains the same as before changing to 31 - it just switches to talk mode. Ok. But neither Visa Test Panel nor NI I/O Trace can receive it (checked on the sound device)...

author: Mikhail_K
author_rank: Contributor
timestamp: June 19, 2023, 05:20:41 pm
content: And yes, I suspected the HW fault from the very beginning, but externally all the signals look good. But controlling is ok. There might be a problem with transmission by data lines, though - I see some data on oscilloscope, but it may by just transmitted TO the device, not from 3458

author: Mikhail_K
author_rank: Contributor
timestamp: June 19, 2023, 05:28:14 pm
content: These are three-state 75ALS160 for data lines. Ready-available in the store for around $15. Buying 75psc I could get them at $6 each. Sounds like a good deal for somebody owning several dozens of broken 3458A's. Not my case))

author: IanJ
author_rank: Unknown
timestamp: June 19, 2023, 06:29:11 pm
content: Might be worth looking at this also:GPIB Failure Service Note:https://xdevs.com/doc/HP_Agilent_Keysight/3458A/service/3458A-13A.pdfIan.

author: Mikhail_K
author_rank: Contributor
timestamp: June 20, 2023, 06:36:51 am
content: I checked it as well, SRQ works properly. And this SN probably issued for an older A5 board revision. I have a small one.

author: Mikhail_K
author_rank: Contributor
timestamp: June 21, 2023, 07:21:57 am
content: It appeared that I need to be patient for another week to get the IC - not everything listed in the shop as available is available immediately. But why just wait - I have (I thought so) another way of testing the GIPB - the Soviet Bus Analyser made after HH39401A! This heavy monster's front panel resembles the HP one, but inside you can see around 220 low-scale TTL IC's in similar to SN54 series cases. Bus transmitters are not bullshit integrated circuits - they take 2 boards (8 channels each) with transistors to send and optocouplers to receive data.Once the device allowed me to find the problem in Solartron 7081 - some blind dumbass after partial disassembly of the device inserted the internal GPIB connector so, that a couple of pins were broken! Ok, ok, that was me:) That time I could identify the broken bus line.But here I faced another disappointment - after moving from one shelf to another the analyzer failed to turn on. And the reason was a burnt 5A fuse. It is a 5V supply fuse. Considering the number of IC's consuming the 15-20mA each, there is no big safety margin - at least 4 amperes are definitely required. Quick short-circuit search gave no result - there is no measurable short circuit... So, now I have two toys to repair.

author: Mikhail_K
author_rank: Contributor
timestamp: June 24, 2023, 06:57:02 pm
content: The bus analyzer was repaired and I could check the 3458a's against each other. I put devices in Talk mode and saw the following: the working one will output 18 bytes (ASCII-coded display value) followed by EOI. Another one will send the first byte (Space or Minus) and stall until the next switch to normal/talk mode. As I can see the data lines are ok for both send and receive, so I will not replace SN75ALS160 (even though I've got it today). From the manual to HP59401A I've found that the tri-state outputs of the bus drivers might be damaged if another controller interferes to the bus. So I suspect the SN75ALS161 has failed. It's not that fast to get, so the repair is postponed.PS What a fool I was a couple of months ago offering the bus analyser for sale! It's so beautiful when dynamically reads the bus! Will never part with it!

author: Mikhail_K
author_rank: Contributor
timestamp: June 28, 2023, 07:18:15 am
content: Update on June 28: bus drivers replacement didn't help.I couldn't wait for the delivery of the SN75ALS161 for another 2-3 weeks and looked through all my devices to borrow one. And - bingo! - the Tektronix GIPB module has it! While it is not ALS, swapped the one in 3458A. No changes - same problem with Read. Ok, as long as I am there, tried the new SN75ALS160 (data lines). Same result - no reply to "ID?" and just the first Byte sent in the talk mode. I returned all the components back and checked the Tek module - it works fine.Checked another time the ground connection of the GPIB connector. It's good.The next stage of GPIB interface is the TI MP9914FNL ASIC. In the Tek module there is its pin-to-pin and SW analog - NI NAT9914BPL. But while I can easily desolder and move it to 3458A, the return will be problematic - the components on the Tektronix board installed quite tight (see the picture). I might destroy it and get no results. Moreover, this NI component supports 488.2 - will it work with the current FW? There is another obtainable (I think) component - programmable timer MC68B40CP. It's followed by Xilinx. So, I can't go further than MC68B40. Anyone came that deep in the GPIB IC's replacement? Is it worth trying?

author: Mikhail_K
author_rank: Contributor
timestamp: July 02, 2023, 11:45:31 am
content: My body is here, in Xanadu Island hotel, but my soul is with the sick GPIB of the 3458A))

author: Mikhail_K
author_rank: Contributor
timestamp: August 14, 2023, 10:05:22 am
content: Happy end! The reason was a failure of MP9914FNL. While there was an input signal NDAC rise from active to non-active on its pin, there were no expected reaction - rise from active to non-active DAV in reply. The handshake will stall. This action does not depend on any other input, so I boldly swapped the IC.While turning the device on and off I noticed quite a big hysteresis - from 0,4 to 1 ppm, so in the mean time I put my old '96 A9 which is much better. I have added 110K in parallel to 15K in the "new" A9 (from '04) and will wait for some time before swapping the boards again. I have to notice, that both boards are quite stable when warmed up and the issue is with this thermal hysteresis only.Is there anyone who realised backup power supply for the reference inside the 3458? Seems not so difficult assuming a free space in the A5 board's compartment.