Are AUI to AUI Null Cables Possible?

Mike Harvey asks: "Hi, after obtaining a SparcStation 1 I realized I have no way to connect it to my network. I know I could go out and buy a transceiver for it, but, as one of the really poor students of the world, I was wondering if it was possible to do an AUI to AUI null (or crossover) cable, and whether it would work to connect it to a second net card in one of the other computers? I could just try it, but I would prefer not to make either into paperweights."

It works, I've done it!

[bluGill]

Others have given probable wiring diagrams, so I won't attempt to repeat them. At work a few years back I did this, someplace we found a AUI-AUI null cable, and it worked fine. If there were any extra parts they all fit inside a cable hood. I didn't wire it, I just used it.

Most importantly it worked, so if you feel like putting it togather it can work.

I think Sun AUI are non-standard ...

[Etyenne]

... at least on my SS10. The connector is not the familiar DB15 it is on PC hardware, it's more like a dense female 25 pin, very much like the Sun speaker connector. However, I am not really familiar with Sun hardware, so don't take my word for it.

Probably

[h2odragon]

I think an xcvr would be easier, too, but a quick look at a pinout list [pin-outs.com] makes me think it'd be possible. I haven't tried it; I can't recall the last time I saw an Ethernet AUI port. IANAEE (Electical Engineer), YMMV

Get a tranciever anyway...

[olle]

I don't mean to be snotty but, get a transciver...

Actually, go to your uni's network/computer dept. staff and ask for an old one, I bet you they have lots just lying around...

It's the only sane way to get any use out of the old relic....

/olle

Re:AUI to AUI

[BJH]

Acch!! Pfft!! Obviously, I didn't mean a mailing list - it's from an old Usenet post in comp.dcom.lans.ethernet.

AUI to AUI

[BJH]

Found this on a mailing list - hope it helps (but it really would be easier to just buy a transceiver).

Ethernet AUI to AUI cheaply [ask.ne.jp]

I hate to plug ebay but...

[Saihttam Yrrebnarg]

Take a look at the auctions and find a cheap transceiver. If you have ancient AUI hardware, then you probably wouldn't mind used transceivers either. They'll run you about $10 or so a piece, which is about what 10baseT netcards run at swap meets, etc. If you are in the Dallas, TX area, take a look at first saturday (www.1stsat.com), but the things happen in most big cities.

Look for old stuff that no-one wants, but are still useful -- unlike AUI cards. If you are looking for it for a sun machine, I can sympathize with you, though.

Be very aware of what you are doing...

[DFDumont]

I looked at the wiring diagram posted above and noticed a few things:
1. There is no feed-back capability, thus the machine in question will not receive its own packets. This is a violation of all the IEEE rules and will likely reek havoc on all but the most stable IP stacks.
2. The collision detection pin is diliberately grounded, thus this is a FULL DUPLEX connection.

Both points can be handled IF AND ONLY IF you can configure the device driver to accept a full-duplex configuration, which is unlikely for a driver meant to work across an AUI. You may find that it works, sort of, under light load.

I agree with the other posts, the transceiver is the best alternative. The microtransceivers are running $35 or so, retail.