Tea Timer
Brewing tea is a simple process of using water to extract the bits from tea leaves. Top minds have been doing this for several years, coming up with a general idea of how long one is meant to leave the leaves in the water. Unfortunately, as a rather forgetful person, my usual tea steep of 15-30 minutes falls outside of the expert opinions on the matter. The normal way to fix this would be a phone timer, but my forgetfulness has gained the ability to silence the timer and move on without informing my brain. I embarked on a new project, creating a timer that would force me to collect my tea.
In this post I document this excellent exercise in experimentation and interaction. If learning isn’t compelling enough, I suggest watching this video of the finished timer to be overcome with jealousy:
Now the easy solution would be to buy an egg timer and put it near the tea kettle but that would make this a rather short blog post. Also, it would cost money! Outrageous! Instead, I set my sights on the free-right-now-since-I-paid-for-it-in-the-past Adafruit NeoTrellis M4. With 32 light-up buttons and the ability to play back sound files it was the perfect block of wood to hack out a timer that would get the job done.
After a short montage of AdaFruit’s excellent tutorials and my own CircuitPython programming, I had a useful creation. Pressing a button (mapped out on the colors of the leds, very straightforwards!) would result in a timer counting down and reminding me of my tea’s existence with a bright flashing light in my peripheral vision. Now that I finished this project, it was time for the project to really begin.
Wait, what?
It was terrible! I had to power cycle it every time I wanted to start a new timer! That’s the worst! It was time to sand all the splinters and other sharp bits off of this unfinished hunk of wood.
Shoring up the foundation
But first it was time to clean up the code, the coolest and most exciting thing
to do at any stage of a project. It was tempting to cut out this part of the
post–silently suggesting that a divine light had guided my hand towards
perfect code even while quickly iterating through versions–but no, there were
flaws. The spring cleaning on the agenda was to trim away all of the
unnecessary tutorial code and to replace hardcoded colors with the excellent
fancyled
library’s palettes. Emboldened by this easy progress, I also threw
in some audio with the idea that I would someday hook up an external speaker to
the Trellis.
Start again
The sharpest splinter on the board was having to restart the Trellis to get
another timer going. I took all the code that ran the timer, shoved it in a
forever-looping while True:
, and moved on with my life. Well, moved on for
as long as it took me to test the timer, as this shove-based coding (inspired
by my shove-based cleaning) meant that the same button press that stopped the
timer would also start the next timer due to the critical lack of a delay
between loops. One delay later and I could finally plug the Trellis in by my
kettle and call it a day.
Wait! It’s still bad!
After a few weeks of using my beloved tea timer I had a couple of Notes. First, one of my fussier teas demands a 2 minute 30 second steep. With my minimalist inputs, that wasn’t happening and the leaves were crying. Next, I could still (somehow) miss the dramatic flashing lights coming from my speaker-less Trellis. When I’d finally rush to the blinking beacon in disarray, it would also not let me know how long it had been trying to get my attention. I bought a cheap speaker that may as well have been purpose-built for using with the Trellis and solved both of the later problems. Finally, through learning to stop worrying about tea-crimes I laid the first problem to rest.
The timer was still mediocre though, stay tuned for the thrilling conclusion of our saga!