Since I am apparently obsessed with the Enigma cipher machine, I decided to make the most minimalist and yet functional Enigma M4 simulator I could think of. TINY84A running at 1 MHz on a CR2032 battery. I was very careful with power savings so it essentially sleeps taking only around 150uA when on plus the LED power consumption. When in soft OFF mode (5 minute timeout), it uses less than 0.1 uA! I'm using some Kingbrighi HELI2 LED's which produce an amazing amount of light for extremely low current as well. Bright LED's in this example are only using 157 uA each, giving it an estimated number of runtime hours for a single 25 cent CR2032 at ~240 hours.
Not seen in the video is a recently added Morse code mode that will show you the Morse code for any letter entered. I also added a blinkenlight's mode where you can display various sequences of either random lights, lights moving left and right, etc. And of course it can encrypt or decrypt Enigma M4 (and thus M3) messages. These pcb's are oshpark purple, but I'm going to try some other colors too. The HELI2 LED's are also available in orange, red, yellow, and blue, though they use 50%-100% more current than the amazing green ones. I've got a TVS diode and a fuse for some circuit protection on the back especially since the CR2032 positive side is exposed.
What have you guys been working on lately?