How to Add more Input and Output pins to Esp8266 by Manmohan Pal

In this tutorial, we will learn how to expand the input and output pins of ESP8266 NodeMCU using a shift register (74HC595) for digital outputs and multiplexer/analog techniques for analog inputs. The ESP8266 has limited GPIO pins, but by using external ICs, you can easily control more LEDs, sensors, and devices.

We will cover:

Why ESP8266 has limited GPIOs

Connecting 74HC595 shift register to increase digital output pins

Using CD4051 analog multiplexer to add more analog input channels

Circuit connection and explanation

Example code in Arduino IDE

This method is very useful for IoT projects, home automation, and sensor monitoring systems where more pins are needed than the ESP8266 provides.

✨ Tags:
ESP8266, NodeMCU, shift register, 74HC595, analog multiplexer, CD4051, increase GPIO pins, add more input pins, add more output pins, Arduino IDE, IoT projects, electronics tutorial, ESP8266 projects