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Comment on Show HN: I made an Ethernet transceiver from logic gates

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This is a wonderful project! I'm old enough to remember the days when Ethernet adapters for commercial computers were made of individual logic gates. The Ethernet adapter in the VAX 11/750 I used in the early 80's was two large Unibus boards full of TTL logic: http://gunkies.org/wiki/Digital_Ethernet_UNIBUS_Network_Adap...

This blog post dives into another mostly TTL logic Ethernet board from the Xerox Alto: https://www.righto.com/2017/11/fixing-ethernet-board-from-vi...

It has a nice high level diagram of what each group of TTL chips is doing too:

https://lh3.googleusercontent.com/-DpUyda3g2Yk/WgB7G_7o54I/A...

The one that superseded that, the DELUA adaptor, was powered by a 68000 CPU that was generally faster than the machine hosting it :-D

That is crazy, the amount of space a network adapter took up.

First PC network card was only slightly smaller :)

3Com 10Mbps Ethernet 3C500 aka IBM Ethernet (IE) aka EtherLink from October 1982

https://static.wixstatic.com/media/a03cac_005e3e9eb62b47c292...

And there were a few more boards for the disk controller, and another couple for the display controller…

Not to mention all the boards that the CPUs and RAM took up. Here's a nice photo of the insides of a VAX 11/780 - if you enlarge it all the way you can see the annotations showing which boards do what: https://upload.wikimedia.org/wikipedia/commons/e/ec/SPEC-1_V...

Note that those 16 huge memory boards each held 256K (kilobytes!) for a total of 4M of RAM.

Photo with people to show size of cabinets: https://photovault.com/363660

It’s always surprising to look back at these things, because it hardly seems like it would be economical to build and deliver such a huge monstrosity.

When the alternative is nothing or paying a lot of money for something you need to make a lot of money, people will pay a lot of money. It still crazy though. The 80s don't seem that long ago.

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