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Originally Posted by Carl@Semroc
We had to interface with some old IBM RTL logic boards, but everything we did from 1971 was TTL. 7400 series was on all the production boards when I started.
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I didn't realize it went back that far.
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I remember that I had to memorize most the Texas Instruments TTL Databook...
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I still have mine. It was a required text book in college, believe it or not.
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When Intel introduced the 8008 microcomputer, I built a 7400 based board that executed the 8008 instruction set at 20 times the speed. Still no interest from Telex. The good part about it is that I always had a faster and better microcomputer in my basement than you could buy on the market. 
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I was surprised by that attitude in college. The professors were focussed on 500khz 6800 microprocessors, and even then I realized I could roll my own CPU out of discrete logic and bit slice that could run 10 or 20 or maybe even a 100 times faster. I think that was probably still true until the 68020 or 486's came along. Heck, Cray was still doing it that way for another few years until 500MHz processors overtook his stuff.
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I still design with 74HCT as glue. I just can't see the numbers on the surface mount parts. The sick joke is that as the early logic designers lose their eyesight, the IC companies make the parts even smaller. I used to laugh at my elders at Telex that carried a jeweler's loupe to see the parts back then. I did not realize I was laughing at my future self as well.
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It's even worse now with laser branding. It's danged faint. And the light must hit it just the right way to get a good read. I actually have to use a stereoscope in the lab sometimes
Even then, that parts are so small now that we have to create encoded part numbering tables in the datasheets. The user reads a 4- or 5-character number off the IC package, then looks it up in the datasheet to get the complete umpteen character part number. If you don't already know the root part number, you won't know which datasheet to use. In some ways, the parts might as well be not branded
I don't think the various divisions within the company here cooperate on the encoded strings, so two entirely different parts, such as an op-amp and a temp sensor, which happen to share the same tiny package, such as a SOT23-6, might have the same encoded marking. So even if you can read the number, you still won't figure out what it is
Doug
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