You can turn a single analog pin on a microcontroller to a 4-bit input with 1-bit output with only some resistors, push button switches, an LED and a single JFET… It has been done forever… ...

DIY Button Matrix Lights Up And Speaks I2C May 17, 2019 by Donald Papp 2 Comments [David Johnson-Davies] always wanted an illuminated button matrix for projects, but cost was never very friendly.

Arduino RGB Matrix Shield 10:07 am June 21, 2018 By Julian Horsey Adafruit has this week announced the arrival of the new Arduino RGB Matrix Shield which is now available to purchase priced at $5.95.

Created by the Lenka Design Workshop the case has been created using a 32×32 LEGO baseplate finished with a clear acrylic cover to house the four large arcade buttons and Arduino board, LED ...