In most keypads, pressing a key closes a contact that bridges two lines in an xy matrix. If you use a microcontroller to detect a key closure, checking the states of (x+y) lines requires an equal ...

A lot of making goes on in this community these days, but sometimes you’ve just gotta do some old fashioned hacking. You might have grabbed an old Speak and Spell that you want to repurpose ...

Traditionally, interfacing a microcontroller with an n-by-m keypad required n + m of the microcontroller's I/O pins for keypad scanning. Keypad designs that conserve microcontroller pins have been ...

16-button keypads have a clever method of encoding their data into 8 pins. Pins are mapped to four rows and four columns on the keypad. A user reads the keypad by bringing each row up to logic: HIGH, ...

This circuit uses Microchip’s PIC16C71, an 8-bit microcontroller, to create a digital voltmeter with an LED display and a keypad. To view the application note, click on the URL below. Circuit selected ...

If you would like to build your very own Macropad shortcut keypad you may be interested in a new project published to the Hackster.io website by member Naveen. The builder is classed as an ...