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Comment by AlbertCory | Hacker News Reader

A really fun bit of trivia that I discovered in researching my second book was: DataPoint, arguably, sold the first personal computer.

I'm sure you don't believe that, if you've even heard of that company. They were huge in the 70s, a public company, and they had a terminal that did not require a mainframe connection, i.e. a PC.

Their concept of a PC, though, was "You can do your data entry offline, and then when you're connected, you upload the data! It's magic!" No third-party apps, no "apps" of any kind, and of course not for retail sales.

They also had a LAN, ARCNet, which was a 4MB token ring that ran over regular twisted pair. It was solid, too.

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Arcnet was really widely used-- in fact, it's still somewhat used in industrial control systems. Compared to Ethernet it was extremely robust and somewhat less expensive. Although it was a fair bit slower it tended to hold up better under load.

I've probably still got some ISA arcnet cards kicking around in a box someplace.

"extremely robust" is no joke. I once saw someone win a bet by successfully running Arcnet over a barbed wire fence.

How far? I once ran 10Base2 over dozens of meters of twisted pair for doorbells. The ISA 3c509s just made a very high pitched sound, but didn't get extraordinary warm, smelled funny, or smoke. Otherwise everything normal. Worked. For a few days, until the 'real stuff' arrived :-)

300 feet/90 meters or so or so? It was a fence running along the property line adjacent to two buildings. I remember there being enough room to park a couple tractor-trailers between them, so 300 feet sounds about right.

You win! :-)

Gordon Peterson, the chief architect of it, told me that he had a standing bet with his QA engineers to buy them a steak dinner if they found a bug. He didn't need to buy very many.

Arcnet was 3 Mbps, I think. Linux had drivers for it until after 2000, and pushed IP packets through it. People loved their Arcnet.

Apple, meanwhile, had AppleTalk over RS-422. Was it 1/2 Mbps?

AppletTalk was 0.23 Mbps.

Arcnet was a token bus (like IEEE 802.4 from General Motors' MAP) and not a token ring (like IEEE 802.5 from IBM's Zurich research).

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