Made a shot bot for my tamp mat

I made something people here might like. 

I’ve been making espresso all willy nilly for ten years. As a generally lazy person, I never really tried to improve them, so it was only recently that I bothered to measure anything. Weighing ins and outs led to better, more repeatable shots, but came at the expense of all the fiddly nonsense associated with using the scale. 

For $20 I bought a “Cheap Yellow Display” to talk to the (admittedly not $20) Bookoo scale and incorporated it into a tamp mat. This solved a few problems:

1. The display doesn’t sit under my $@#%ing cup so I can actually see it.
2. It knows the weight of all my stuff, so I never have to tare anything.
3. It watches the rate of flow and does a little audible count down to “done” at just the right time.
4. It lets the next person know how the last shot went for grind adjustments (too fast, too slow, just right)
5. It knows the weight of my cup vs my wife’s cup so we can have different ratios.
6. /jerk It opens up a new world of statistical stack-ranking and allows me to promote lesser performing butlers to street-urchin.

It was a fun little project to explore LVGL and these cheap-as-dirt ESP32 displays as well.

Here's a little movie of the UI doing its thing: https://www.reddit.com/user/TinyRobotBrain/comments/1ri9yss/video_of_shot_bot_ui_for_respresso/