Pointless Blinking With Python, asyncio, and libgpiod (and a Raspberry Pi of Course)
04-15, 13:00–13:45 (Europe/Vienna), HS i1
Language: English

One of my more pointless projects is to blink a configurable set of
programmable patterns on a number of LEDs. This might sound like "hey,
you are reinventing the wheel". I admit I do - I am a notorious
reinventer, and it is fun.

Lets reinvent LED blinking in a live-hacking session, and look into a
number of topics as we go:

  • Python is a programming language that most of you know. It is simple
    and expressive, thus fun.
  • Python's asyncio is a parallel programming technique, similar to
    multithreading in its usage, but fundamentally different in every
    other respect. At its core, it maps multiple parallel control flows
    onto one single-threaded event loop. Given that timers are events,
    this gives us the possiblity to run multiple LED blinking programs
    in one single thread - saving all the context switching and
    scheduling overhead that multithreaded programs usually
    exhibit. Blinking with less glitches caused by context switch hiccups!
  • Ah, blinking patterns. Know what Python decorators are? Closures?
    We'll twist our brains and create a @program decorator,
    implemented as a double-closure, and use that to write a number of
    amazingly simple blinking programs. Almost like functional
  • Last not least, libgpiod. The way to go for GPIO on Linux.
  • Born in Graz, and bound to die in Graz
  • Been around as an employee in and around Graz for many years
  • Self employed as trainer and consultant for even more years
  • https://www.faschingbauer.me