IEC 61131 is the automation guys bread and butter, but apart from it, every machine smarter than a induction motor seems speaks it own variant of ugly QBASIC.
Learn to grok those, get good, have a proof of it and there are plenty of jobs.
I mean every guy can do simple "put an input in in these circumstances" like things in them, but dare to use the buggy and feature-depleted networking/gui/string manipulation utilities the programmers put in probably thinking no-one is going to use them anyway, you need some good wits, because the thing is literally a black box, sometimes you load the thing in with FTP or serial and the blinking lights at IO board is all you get to show that the thing is doing what you inted to. No debugger, though there will be bugs - hardware bugs! And bad, insufficient, badly translated documentation, no user community to get help from; maybe a manufacturer hotline which will tell "gee, I dunno" if you are lucky and privileged.