Well, it's by ESR so the smug pedantry is taken as read. It may be stuff every hacker used to know (and I'm old enough to have dealt with everything there other

Well, it's by ESR so the smug pedantry is taken as read. It may be stuff every hacker used to know (and I'm old enough to have dealt with everything there other than the 36-bit stuff) but so what? There's a ton of stuff going on these days I'm too old to care about and don't know but younger hackers probably have forgotten they ever had to learn it. Modems are still connected via serial lines - our embedded project has a modem connected to the MCU via a UART. We ran out of MCU pins for HW flow control but it's essentially the same as how we did things in the 80s with external modems. I assumed AT commands were still in use either because they're so easy to use or they're easy to test. I can't say whether the autobaud feature is still useful but the modem we use can do it. I think (some) IoT devices can still use RS-485 which seems similar to RS-232. We're in ag-tech so the sensors we talk to use SDI-12, a shared bus serial protocol with 12v power and 5v signalling. Lots of weird stuff out there!