i2c - Does an I²C IO Expander needs additional resistors for outputs? - Arduino Stack Exchange
Interface MCP23017 (Port Expander) With Arduino Uno - YouTube
MCP23017 - i2c 16 input/output port expander : ID 732 : $6.95 : Adafruit Industries, Unique & fun DIY electronics and kits
Problem with an I2C Pin Expander - General Electronics - Arduino Forum
PCF8574 i2c digital I/O expander: Arduino, esp8266 and esp32, basic I/O and interrupt – Part 1 – Renzo Mischianti
Adding an MCP23017 16 port IO expander to Arduino or Esp8266 or Attiny85 or…….. – Arduino, ESP8266, ESP32 & Raspberry Pi stuff
How to Use Port Expanders on the Arduino - Circuit Basics
Control/Synchronize Hundreds of Relays at the Same Time - Hackster.io
MCP23017: Have you run out of I/O? This chip is the answer!
PCF8575 i2c 16 bit digital I/O expander – Renzo Mischianti
EZ-Expander
Arduino and PCF8575 I/O expander examples - Arduino Learning
49 MORE PINS PLEASE! PCF8574 Arduino Pin Extender (Easy) - YouTube
Arduino Interface PCA9555 GPIO Expander With Code
How To Extend Your Arduino PWM Outputs- TLC5940 Tutorial
GAOHOU New Open-Smart PCF8575 IO Expander Board Module I2C to 16IO for Arduino: Amazon.com: Industrial & Scientific
EZ-Expander Shield for Arduino | Arduino Blog
IO Expander For Arduino Microcontroller Circuit Blue PCB With Male Pin Headers | eBay
Low cost Digital and Analog IO Expander Shield | Numato Lab
Buy SX1509 - GPIO expander 16 I/O for Arduino - Botland - Robotic Shop
How to Connect an MCP23008 I/O Port Expander to an Arduino
SparkFun 16 Output I/O Expander Breakout - SX1509 - BOB-13601 - SparkFun Electronics
Adding an MCP23017 I/O Extender to Arduino or ESP8266 - Instructables
Arduino I/O Expander – Halx4
Arduino Port Expander — ESPHome
SX1509 I/O Expander Breakout Hookup Guide - SparkFun Learn
Low cost Digital and Analog IO Expander Shield | Numato Lab
