ESP32 Rotary Display Makes Ideal Timer

Weβre big fans of pushing hardware into situations it wasnβt designed for here at Hackaday, but sometimes youβve got to appreciate a nicely designed gadget doing more or less exactly what it was intended for β especially when itβs courtesy of code thatβs freely available for you to run and hack on however you like.
Thatβs precisely what [mircemk] has done with their βUniversal Timerβ project. The 2.1 inch CrowPanel βRotary Displayβ at the heart of the build combines an ESP32-S3 with a 480Γ480 round touch screen display and a rotary encoder.
The all-in-one device β clearly meant to be reminiscent of the Nest thermostat and similar commercial offerings β is technically all you need, but in this case itβs been joined by a PCF8574 I2C I/O expander which in turn is used to drive a buzzer that provides a bit of audio feedback at the end of the countdown.
With the code [mircemk] has provided flashed onto the board, the rotary encoder ring built into the housing makes for an exceptionally intuitive input for setting the desired time. Itβs a bit like a high-tech version of the classic kitchen timer, as shown in the video below, you simply twist the ring and the graphics on the display rotate accordingly. Unlike grandmaβs clockwork timer of old however, this one can change color as it nears zero, which makes it easier to estimate how much time remains from across the room.
As the popularity of smartwatches has brought the cost of these circular displays down, weβve started to see some very slick projects utilizing them. The various efforts to turn them into desktop βradarβ displays for nearby flights are a particular favorite.
