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

M

#### Michael A. Terrell

Jan 1, 1970
0
Joerg said:
This one was actually realtime. Stopping the cold-rolled steel line was
not an option, ever. The contract specified that it be run as usual.
Then they had to detect flaws in the material while it was passing
through. My father said the real challenge was the data acquisition
because there would be the occasional splat of grease falling off the
gears of overhead cranes and right onto the steel.

Still, no parallel interface at that time could have run the length
of a steel mill with any speed.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

J

#### JosephKK

Jan 1, 1970
0
Michael said:
Real time for that system, was probably on the order of several
seconds. Armco Steel, in Middletown Ohio, built a computerized hot
strip mill at that same time, using a huge 5 MB hard drive (40 inch
platter?) with a 5 HP three phase motor. (I ended up with the three
phase breaker box, with the ENGRAVED warning plate "DO NOT ENGAGE DISK
DRIVE FOR FIVE FULL MINUTES").

Serial communications HAD to be used, because the mill was over a
mile long. The computer system was replaced in the mid '80s when they
had purchased the last remaining Westinghouse hard drive in the world,
and no one was rebuilding them.

With that big motor it may well have been drum instead of disk. The
largest disks that i have heard of were 24 inches. Doesn't mean that
there weren't larger.

J

#### Joerg

Jan 1, 1970
0
Michael said:
Still, no parallel interface at that time could have run the length
of a steel mill with any speed.

True. I just wanted to say that they did it serially and it worked.

M

#### Michael A. Terrell

Jan 1, 1970
0
JosephKK said:
With that big motor it may well have been drum instead of disk. The
largest disks that i have heard of were 24 inches. Doesn't mean that
there weren't larger.

There were drums with that capacity, but this was a custom designed
disk drive built by Westinghouse and sold to a couple dozen heavy
industry customers, worldwide. A friend of mine was an ET at that mill
and helped dismantle it, after it was decommissioned. One of the biggest
problems was the horrible seek times. They got the new computer system
on line. just in time, because the disk crashed during the changeover.

--
Service to my country? Been there, Done that, and I've got my DD214 to
prove it.
Member of DAV #85.

Michael A. Terrell
Central Florida

J

#### Joerg

Jan 1, 1970
0
Robert said:
Hi all,

Just for your information we have just developped and commercialized a new
http://www.alciom.com/en/smart488.htm, but my goal here is not to promote it
but to answer to the OP...). On the hardware side such a project is not that
difficult. We haven't used a FTDI chip plus a microcontroller as Prologix
did, but a single USB-enabled microcontroller (a Microchip 18F4550), which
allows us to build a more compact device and to simplify advanced firmware
features like firmware download through USB and no driver required on the PC
side. However the firmware side for such a project is far more complex. GPIB
basics are quite easy to understand as long as you buy the IEEE488 specs,
but making such an interface compatible with a significant number of GPIB
equipments is not that easy. If you develop such a product yourself take
care of the EOI subtilities in particular...

No pun intended, Robert, but the Prologix over here seems to be cheaper
than the the price your French distributor charges:

http://www.sparkfun.com/commerce/product_info.php?products_id=549
versus
http://www.lextronic.fr/P3171-cordon-dinterface-usb--gpib.html

But I guess that's because the USD/Euro exchange rate has pretty much
flipped around within a couple years. Is there a chance your adapter
will be marketed in the US anytime soon?

For future versions you might want to consider a separate USB cable like
on the Prologix. The main reason is that large analyzers must often be
pushed close to the wall because of their depth. That requires a USB
connector so you can insert one of those right angle adapters and then
the USB cable. Otherwise there is a chance the USB cable will be bent at
too sharp a radius or even hit the wall.

J

#### Joerg

Jan 1, 1970
0
Robert said:
"Joerg" <[email protected]> a écrit dans le message de
[email protected]

Hi Joerg,

Yes, we hope that the US$will be higher soon... and I think we are not alone to have the same hope over the world ;+). A 60% increase of the$US to
Eur exchange rate in a couple of years is not really understandable, at
least by an engineer !

It is an over-reaction and might be turning around now but who knows.
It's even less understandable in view of inflation levels in Europe. I
thought they must be higher here but yesterday we had an article in the
morning paper about a French couple just outside of Paris. Even the
They had a combined annual net income of around 40000 Euros and lived
frugally but ran into overdraft on their bank account every month.

I still miss the cheese section of the Carrefour supermarket ...

As soon as a distributor will ring us ;;+).

If they find it. HPIB isn't a hot bus anymore, you might have to ring
them instead of waiting. Or as one family here put it when their
daughter was considering not going to a certain party: Mr. Nice Guy
isn't going to come along on a white horse anymore these days. She found
Mr. Nice Guy on that party and they are getting married ;-)

We hesitated twice between the option of a fixed USB cable and the use of a
standard type-B USB connector. We finally decided that the fixed cable
option was better just because it is more reliable. You're right, cable may
be deteriorated, but we didn't want to have the risk of disconnected type-B
connectors behind a pile of a dozen heavy equipments... Moreover the built
in cable allowed us to have drastically better EMC results...

Yes, EMC is a pain with USB. Loose connector aren't such a problem.
Happens all the time. Did I plug in that BNC? Oh no ... move that
freaking heavy HP4191 back out, plug in, push it back, take pain pill
before the sciatic nerve flares up again.

F

#### Fred Bartoli

Jan 1, 1970
0
Joerg a écrit :
I still miss the cheese section of the Carrefour supermarket ...

Uhhh?

So you don't know what real good cheese is then.

J

#### Joerg

Jan 1, 1970
0
Michael said:
Joerg, heavy test equipment should be on an equipment cart.

<http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=92862>
<http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=5770>
<http://www.harborfreight.com/cpi/ctaf/displayitem.taf?Itemnumber=5107>

are some examples. Every bench at Microdyne had at least one cart. The
industrial carts they bought were just the right width for the HP
equipment, but we also used a couple pieces of 2" * 4" lumber and a
piece of plywood to use them with other equipment. A six to eight inch
gap at the front left room to store cables under the plywood. The only
time equipment had to be moved off a cart was when it went to the cal
lab. Even then, sometimes the whole cart was wheeled to the lab. If it
passed their tests, it was wheeled back. If not, that item was removed
from the stack and replaced with another piece of equipment from the
shelves of spare parts.

I use both the second and third in the list in my shop.

Those can easily tip over. I don't think OSHA would let that fly in
California. Most labs are like mine. A wide bench and a rack in the
back. The equipment gets shoved it that rack and you have to make sure
all required connections are there.

J

#### Joerg

Jan 1, 1970
0
Fred said:
Joerg a écrit :

Uhhh?

So you don't know what real good cheese is then.

Well, I haven't been in one in a decade or so but back then they had a
huge selection. In the US we can't get really good camembert or brie
because of the pasteurization requirement.

Of course, even in France I preferred the little fromage shops. That's
where the really good stuff could be had. Where you take a bite of brie
and your respiratory system stalls for a second.

J

#### Joerg

Jan 1, 1970
0
Michael said:
Not with the weight distribution we used. The carts were over 100
pounds, and the load was centered on the cart, along with items stored
on the bottom shelf. They used them that way at that location for over
20 years. At the peak of production they had two techs per 8' bench,
with most of their equipment on carts. That was when they were trying to
keep up with the demand for their 1100 series C-band satellite TV
equipment for CATV and broadcast customers. The only time anything
tipped over was when two idiots tied to move a loaded 8' workbench,
without help. When all four wheels swivel, it is almost impossible to
turn one over.

Until the cart hits a large extension cable on the floor. I've seen it
happen.

J

#### JosephKK

Jan 1, 1970
0
Probably it is not a difficult project- but, I don't think one can make one
that easily- NI has probably patented all of its hardware. But, then, I
don't know how prologix is able to make it.

All the basic patents on GPIB have run out long ago, they belonged to
HP anyway. Even the NI patents (relating to IEEE-488.2) are getting
long in tooth. (about 15 years old) The converter is not particularly
hard, but you will have to learn IEEE-488 etc. well to make it.

Replies
6
Views
2K
S
Replies
2
Views
3K
S
Replies
0
Views
2K
spamme9
S
S
Replies
1
Views
2K
Pierre-François
P
K
Replies
0
Views
1K
K