The keypad module, available in the latest CircuitPython 7.0.0 builds, scans a set of keys or buttons in the background, and gives you key-pressed and key-released events. The keypad module provides three different kinds of scanners:
Keys: Each key is connected to a separate pin.
KeyMatrix: The keys are wired in a row-column matrix, with or without diodes. This is typically how typing keyboards, music keyboards, and telephone-style keypads are wired.
ShiftRegisterKeys: The keys are connected to an external parallel-in serial-out shift register. The keys are read by clocking data from the shift register into a single input pin.
Each time a key is pressed or released, a scanner will record an Event in an EventQueue. Each event gives the key number, and says whether the key has been pressed or released. Your program can read the events sequentially.
The background scanning does debouncing as well, so you don’t have to worry about handling that yourself.
Check out the new Guide: we’ll explain how each of the scanners works, and give you some simple examples.
8-6-2021 (August 6, 2021) is the Snakiest day of the year and it’s also this year’s CircuitPython Day! The day highlights all things CircuitPython and Python on Hardware. See you there!
Stop breadboarding and soldering – start making immediately! Adafruit’s Circuit Playground is jam-packed with LEDs, sensors, buttons, alligator clip pads and more. Build projects with Circuit Playground in a few minutes with the drag-and-drop MakeCode programming site, learn computer science using the CS Discoveries class on code.org, jump into CircuitPython to learn Python and hardware together, TinyGO, or even use the Arduino IDE. Circuit Playground Express is the newest and best Circuit Playground board, with support for CircuitPython, MakeCode, and Arduino. It has a powerful processor, 10 NeoPixels, mini speaker, InfraRed receive and transmit, two buttons, a switch, 14 alligator clip pads, and lots of sensors: capacitive touch, IR proximity, temperature, light, motion and sound. A whole wide world of electronics and coding is waiting for you, and it fits in the palm of your hand.