Comment by mikewarot | Hacker News Reader

Comment by mikewarot | Hacker News Reader

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Ladder logic is powerful stuff. I learned it at Westinghouse in the 1980s. It's a non-Von Neuman based programming methodology well suited to real time environments. Every ladder gets executed once per cycle, and there are usually a few hundred cycles per second.

Special functions are implemented in boxes, like delays, counters, etc.

My task back then was to feed the entire I/O state into a ring buffer, and when a "crash" of the steel mill happened, a host PC could then download the entire buffer, giving access to information about what happened in the seconds BEFORE the crash.

It would be fairly easy to port to the Arduino, if someone hasn't done it already. Yep - it's been done https://cq.cx/ladder.pl

Because Ladders are text based, you could use Teco/EDT/Vi/Emacs/WordStar macros on them.

Yeah, it's a pretty neat ecosystem. PLCs are kinda like the Legos of automation, incredibly easy to mix and match with a fair number of (insecure) standard protocols.

I briefly toyed with the idea of building out some open source hardware/software but I didn't really seem like there was enough of a userbase to make it viable. Anyone using it professionally wants support and 10+ years of parts, most maker/hobby projects want direct access to code.

Still some pretty neat concepts for putting together highly customized processes with extensible and interchangeable hardware.

if you show them how insecure their current hardware is, it will sell.

if it supports the old protocol but secure it should be transparent to them

You don't understand how industry works. If it works, you don't replace it, you get it fixed when it breaks. Nobody is going to willingly risk their factory, plant, etc. on some new supposedly better hardware. They'll keep what works going for 100+ years if they can.

It is totally logical for them to do so. The "security" threat can be band-aided over with a new firewall at the internet access. Replacing any component of the control system introduces an element of risk. Downtime is horrendously expensive, and can ruin a business. Only a fool would do anything to introduce the risk of downtime in the name of "efficiency".

I'm sorry about the tone of my other reply. In retrospect it was rude.

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