Is a USB to GPIB dongle/convertor a difficult project ?

You will need at least some buffering memory to resolve timing differences and some logic to resolve commands. I assume your device will look to the host computer like a USB slave, but to the GPIB devices will look like a bus controller.

I think you'd be better just getting an NI USB-GPIB converter. It's not just the hardware compatibility that's important, depending on what software you're using, robust and well tested drivers are critical.

JB

check out ebay item 290206904947 Paul Mathews

AFAIK, there is no single-chip "USB/GPIB" solution.

is a picture of one available (and relatively inexpensive) approach.

Sparkfun carries the newer, 4.2 version; I've use the bare-board rev 3 (the one pictured) with success for some automated lab test equipment.

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Rich Webb     Norfolk, VA

Seems to me that GPIB is, and should be, dying. Everything should just be Ethernet. You can buy an entire Ethernet server gadget, like an Xport, for half the price of a GPIB cable, and it will work 1000 miles from your computer.

Ever read the actual IEEE GPIB spec?

John

The hardware design for a USB to GPIB converter is pretty straightforward -- here's one:

The much more time-consuming problem -- as Paul mentions -- is that writing drivers to the level of robustness that the folks like National Instruments or HP have done is quite time consuming. If you want to build such a dongle for fun or largely self-contained projects, though, this perhaps isn't a problem.

There's more to it... GPIB isn't popular enough anymore for someone to make a single-chip interface for it.

---Joel

USB to GPIB and Ethernet to GPIB converters are the probably the last products that will ever be commercially developed for GPIB.

No, although from having written test programs to talk to GPIB devices I suspect it's quite massive and somewhat convoluted. :-)

---Joel

My Commodore PET 2001 (despite the name it's ca. 1979) does GPIB..

Like this one:

At least nobody will be able to hack into the control for a HV power supply and electrocute anyone.. Best regards, Spehro Pefhany

--
"it\'s the network..."                          "The Journey is the reward"
speff@interlog.com             Info for manufacturers: http://www.trexon.com
Embedded software/hardware/analog  Info for designers:  http://www.speff.com

Anyone know if Softmark products are sold in the US somewhere?

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Regards, Joerg

http://www.analogconsultants.com/

Agree. However, there is lots of legacy gear that will be around for another decade or two. Like the HP-3577. It would be nice not to have to snap a digital camera picture every time.

I'd rather read a Steinbeck ten times in a row ;-)

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Regards, Joerg

http://www.analogconsultants.com/

On a sunny day (Tue, 19 Feb 2008 12:57:57 -0500) it happened Spehro Pefhany wrote in :

Ah yes, I have played moonlanding game on one of those in 79.

Yup. But get hold of a LAN-GPIB gateway (HP E2050A sell for not much) rather than a local bus GPIB card and you'll be ready for the next ISA/PCI/PCI express/whatever bus shift.

I did that because I wanted to switch all my PCs to linux. Plus, I can connect from either my desktop or from a wifi laptop in the lab. Pretty useful.

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Thanks,
Fred.

Where do you find them? EBay was dry. All I really want to do is print the screen contents, not control anything in the lab.

--
Regards, Joerg

http://www.analogconsultants.com/

Joerg wrote: snip

Make sure you don't already have this capability. My TEK scope has a menu buried in the menus that will print a bitmap graphic of the screen out the serial port.

I won't call it GPIB, 'cause it's not anywhere near a GPIB implementation. But if all you want is to send/receive simple commands to a single GPIB instrument via a serial port, you can do it with a PIC processor and a couple of level translators for the serial port. No part of it complies fully with ANY spec. Stated another way, it VIOLATES EVERY spec. But it works for me. Built it specifically to create an on-screen demo of a TEK TDS540 that I was trying to sell at a swapmeet. I set out to write a Visual Basic Class module with the same API as the National Instruments GPIB drivers, but don't remember what happened with that. Got bored and moved on to something else. mike

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Return address is VALID!

Yep, ebay. I paid USD35 (+73 shipping).

There're 2 for best offer right now. I find them way too high (a new E5810A sells for $1000) but if your not hard pressed they pop up from time to time, so just place a search and wait.

I too don't control everything in the lab (the soldering iron isn't).

Seriously, here almost every thing is permanently connected and this has been paid back many many times. Maybe it's worth a second thought...

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Thanks,
Fred.

Well, the HP3577 does offer an HPGL output and AFAIR you could actually connect one of those old HP printers directly to it. But it does not have a serial port :-(

Whatever works to get the HPGL image out would be fine.

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Regards, Joerg

http://www.analogconsultants.com/

I'll have to look again. I've never bought anything there yet and when I keyed in E2050 all I got was some kind of ear rings. And I don't wear ear rings ;-)

I only need screen dumps.

--
Regards, Joerg

http://www.analogconsultants.com/

For the software side, look at the program from KE5FX called hp7470. It captures plots over the gpib and lets you manipulate, compare and store them. I use this with my 8753, 8757, 8569 and 8562 analyzers. It supports the NI and Prologix gpib boards. I have been meaning to try it with one of the NI gpib-serial boxes I have sitting around. Those boxes are cheap and plentiful. Since the Prologix uses a serial port emulator, there may be a chance.

By the way, on your other post about ebay, search for either E2050* or E2050A. If you leave the A off, you will not find any matches.

Doug

Thanks. Yep, that showed it. Along with fashion socks and other stuff ;-)

Seems they now run silent auctions there as well. It appears the Prologix solution would be a bit simpler though. I'll never understand why HP picked that dreaded GPIB bus in the first place, with its expensive garden hose cables and all that. The site of KE5FX is very interesting. In case others want to look:

--
Regards, Joerg

http://www.analogconsultants.com/