61131 has ladder logic, function block, and structured text, which is a pretty eclectic group of programming representations. I think about 99% of the PLC progr

61131 has ladder logic, function block, and structured text, which is a pretty eclectic group of programming representations. I think about 99% of the PLC programs I saw were ladder logic, with the exceptions being Siemens pushing structured text with a C-like look-and-feel. Anywho, cool, robust, reliable things still got made, you just had to think differently. It was very interesting to think about those programs and their relative programming simplicity when compared to complex, modern C++ that is running in other codebases I've seen since then.