The Ratio

28 May 2022

If you find yourself needing to entertain small (or indeed not-so-small) children, it’s useful to know that there are a few things that almost always provide delight vastly out of proportion to their cost. Bubbles, balloons, face paints. Playing with technology is typically an expensive hobby, but here too there are exceptions. In particular (and I’m far from the first to make this observation), microcontroller kits offer a stupendous ratio of money to fun.

In some ways, with their limited capabilities but openness to tinkering, they feel a lot like the home microcomputers of the 80s. However, those were still relatively expensive — even the famously cheap ZX Spectrum was comparable to a decent iPad or Xbox today1. In contrast, the Rapsberry Pi Pico starts at £3.90, literally a hundred times cheaper. If you fry it by wiring it up wrong, or want to permanently embed it into a project, no problem — just get another. This removes a big obstacle to messing around.

Another obstacle has traditionally been the accidental complexity of working with them, but no more. The Maker community and the companies around it — Arduino, Adafruit and many others — have done fantastic work on the tools and development environments, vastly reducing the distance between having an idea and seeing it work. For me, the apotheosis of this (so far, at least) is CircuitPython (and the closely related MicroPython):

  1. Plug your development board in via USB, and you’ll see a drive containing a file called
  2. Edit that file and save the changes
  3. There is no step 3

Removing all of the tooling complexity makes coding for hardware as easy making stuff appear on the screen, and bridges the gap between the two. For someone who’s always been on the virtual side of that fence (even while writing tools for the physical side), it’s a refreshing expansion of horizons.

My only regret is that I’m late to the party. The girls and I have played around with BBC micro:bits and the Meowbit, and done a bit of GPIO stuff with the Raspberry Pi, but the real gateway for me was my recent interesting in keyboards. Now, though, I’m hooked, and if you enjoy messing around with code I strongly suggest you follow my lead and give it a go. After all, what have you got to lose? It’s cheaper than a pack of balloons.

  1. The ZX Spectrum was £125 when it launched in 1982, equivalent to about £500 today. At time of writing, an Xbox Series X is £450 (if you can get one), and a 64GB iPad Air is £569. [back]

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