Here’s my third baby/toddler blinky toy, and first official entry to the canon of IKEA hacks… the blinking high chair, aka the Antiloputer.
The default mode is the same as the blinky my dad made for me long ago: press the red button and the red light lights up, press the green button and the green light lights up, and so on.
Holding down all the buttons at once lets you switch modes: mode two is like mode one, except each light stays on until the next one is pressed. Mode three is like a typewriter, and mode four is a step sequencer.
I suspect the high chair wouldn’t make it through airport security — below is what it looks like inside… Normally, baby legs are protected from the electronics (and vice versa) by a piece of heavy cardboard.
The buttons are attached between the regulated 5v power rail on one side, and pins 10-13 on the other, with a 10k ohm resistor running to ground from each. The LED data is on pin 9, and power for the LEDs also comes from the 5v power rail, through the Trinket. I did this since the 6v coming directly from the batteries is too much for the NeoPixels.
The Trinket can only provide 150 mA, which is pushing what four LEDs will draw at max brightness. Fortunately, the FastLED library has a line where you can specify the max current, and it will dim the LEDs as needed. Genius.
The LEDs are below the high chair tray, aimed up through small holes. I hot glued translucent plastic containers from an art store over the holes, which glow nicely. Be warned, babies are stronger than hot glue, although there’s no danger if the containers get ripped off. You could probably skip the holes and containers, since the LEDs are bright enough to show through the tray.
Also check out the BABYTRON for more blinking.