Re: The joy of FORTRAN

On Fri, 7 Mar 2025 06:17:47 -0500, c186282 wrote:

   A few bits of that digital survived ... adders and ring buffers and
   such. MOST was just thrown into the trash .......

Some things linger on. Before the advent of microcontroller I worked
mainly with relay logic.

https://en.wikipedia.org/wiki/Relay_logic

Programming was done with a spool of 16 gauge MW, strippers, and a
screwdriver. Solid state started making inroads. One I used was Square D's
NORPAK. The heart of it was cards with 10 NOR gates that mounted in a
backplane. Programming still involved strippers and crimpers for the
tapered pins. The NOR gate is the simplest to implement and you can do
anything with it, including getting a massive headache dealing with NORs
and NANDs.

Then the micros appeared. I slowly transitioned from hardware to software.
What surprised me was the ladder diagrams associated with relay logic did
not die. They morphed into PLCs which are still alive today. Under the
covers they are micros but the metaphor usually is ladder diagrams.

https://basicplc.com/plc-programming/

As the first part of that article points out, the logic doesn't change but
the implementation does. I had assumed the ladder diagrams were a bridge
for the older generation of plant engineers but that isn't the case.