Expanding the pins of a microcontroller

By Boris Landoni on September 15, 2023

What to do when the chosen microcontroller doesn’t have enough pins?

We will find out in this tutorial, where we will learn how to use shift registers to control LEDs and read buttons with just three wires!

In six steps, we will use the CD4094 and CD4021 with a PIC microcontroller.

About Boris Landoni

Boris Landoni is the technical manager of Open-Electronics.org. Skilled in the GSM field, embraces the Open Source philosophy and its projects are available to the community.

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