I fell in love with computers by wasting hours messing with Windows settings and internals. Thinking now, it doesn’t feel like there’s a lot of space for that sort of stuff in most people’s routines, especially if they’re stuck in a browsing wheel of boredom. My wheel right now is just Reddit and HN and back and forth, and it’s insanely difficult to unhinge myself from it.
OK then, grab a Raspberry Pi 3B, 4B and Zero, pop open these docs for config.txt, and try and figure out how far you can push each of these tiny machines: https://www.elinux.org/RPiconfig
Really though, the RPi's config.txt is exactly this kind of rabbit hole. I just got a Zero W today and now I'm thinking about if it's possible to underclock it enough to power it with a lemon battery via GPIO.
I have more fun with Arduino type boards than RPis. For me, RPis are just fun to see where you can put a little computer, but I like all of the soldering, bread boarding, wiring, etc of the various shields in the Arduino realm. I get the best of both worlds with the analog/digital inputs, plus the programming in a very limited (requires some creativity) fooprint type of challenge. I haven't messed with the GPIOs on a RPi though, but now we're back to just programming in whatever unsconstrained/unrestricted way of a desktop. ??? we all like different things.
Just install some Linux distro (preferably not something like Ubuntu but something more "bare"/"raw") and start tinkering. I feel there are more tinkers into Linux nowadays than there were PC/Mac tinkers regardless of OS back in the 90s.
Of course computers (including mobiles and tablets) became widely mainstream over the years so the percentage of tinkers dropped but the absolute numbers increased.
