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Standards activities like ANSI are supported by the sale of standards documents, so you can’t normally find them on-line for free. However, I did find the venerable MIL-STD-806B Graphic Symbols for Logic Diagrams online at a DoD web site:
MIL-STD-806B Graphic Symbols for Logic Diagrams
My undergrad advisor used to call this “The best value for your Defense Department dollar ever spent” because of the huge, positive effect it had on the electronics industry (and I presume it didn’t cost that much, compared to programming language standards which can involve a large number of people for several years, just to start with).
It was an improvement over the earlier systems, and I think it is still better than newer standards where all gates are drawn as squares.
I agree. For me, those standards were more visually descriptive than the later square boxes with tiny circles.
When I started everything was True or False, with a True being a positive voltage. Almost all computer logic consisted of AND/OR gates and plenty of Flip-Flops.
It took me awhile to reprogram my brain around 1968 or so when my company converted to High/Low logic with a Low (voltage) being what used to be a True or high voltage. At the same time AND/OR gates were replaced with NAND/NOR gates. More reprogramming for my brain.
But in truth it would require massive amounts of diagrams and schematics to draw today’s LSI logic the way we used to back in the day.
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