I2C Port Splitter Kit (requires soldering)
I2C Shield for Raspberry Pi with Inward Facing I2C Port - store.ncd.io
PCF8574 I2C to 8-bit digital port expander
MCP23008 - i2c 8 input/output port expander : ID 593 : $1.95 : Adafruit Industries, Unique & fun DIY electronics and kits
PCF8574 I2C IO Expander - PCF8574EXPMOD
PCF8574T I/O for I2C Port Interface Support Cascading Extended Module
KeyFob I2C Converter with Dual Serial to 8-Port I2C - store.ncd.io
Amazon.com: Grove I2C Hub - 6 Port with Grove Cable : Electronics
I2C Port ADC Module for Raspberry Pi 3/2/B+ Joystick: Amazon.com: Industrial & Scientific
NANO I2C IO Expander - Hackster.io
Serial Buses — FIRST Robotics Competition documentation
A Guide to Arduino & the I2C Protocol (Two Wire) | Arduino Documentation
I2C — How Does It Work? – Digilent Blog
I2C Shield for Raspberry Pi 4, Pi 3, & Pi 2 with Inward Facing I2C Port - store.ncd.io
How to Use I2C Communication Port - HELPDESK_WJ (Waijung) - Aimagin Support
AK-PCF8575 – I2C 16-bit IO Expander Breakout | Artekit Labs
I2C - DUO Control System
I²C - Wikipedia
I2C - SparkFun Learn
Serial Buses — FIRST Robotics Competition documentation
Mini I2C GPIO port extender (8 bit) – Auvidea
RAK4630/4631 available I2C port - LPWAN Modules / EVBs - RAKwireless Forum
Example: I2C using SC126 and PCF8574 | Small Computer Central
I2C Shield for Raspberry Pi Zero with Outward Facing I2C Port PR19-7
I2C Bus/Interface in Raspberry Pi
