I2C
Contributors:
SFUptownMaker
SFUptownMaker 
Resources and Going Further
I2C is a relatively complex interface, and there are many resources out there to help you deal with it. Below are some of the more informative ones.
- Wikipedia Article on I2C - Not great, but not a terrible place to start.
- Standards Doc - Phillips Semiconductor became NXP a few years back; this is the official standards doc for I2C.
- I2C primer - The official primer on I2C and related technologies.
- Linux Tools for I2C - A nice set of tools for working with I2C and related buses in embedded Linux environments, like pcDuino or Raspberry Pi.
- Open Source Hardware Association: A Resolution to Redefine SPI Signal Names
- Qwiic Connect System
To use I2C over long distances, check out the dedicated PCA9615 differential I2C bus extender.
Qwiic Differential I2C Bus Extender (PCA9615) Hookup Guide
May 31, 2018
Learn how to extend the range of your I2C communication bus with the Qwiic differential I2C bus extender (PCA9615 ) breakout board.
Or check out our SPI and I2C tutorial with a Raspberry Pi.
Raspberry Pi SPI and I2C Tutorial
October 29, 2015
Learn how to use serial I2C and SPI buses on your Raspberry Pi using the wiringPi I/O library for C/C++ and spidev/smbus for Python.
Need some inspiration for your next project? Check out some of these related tutorials:
Qwiic Flex Glove Controller Hookup Guide
Is your finger bent? Is your finger straight? The Qwiic Flex Glove controller board will answer this age old question for you with the flex sensor!
Qwiic pHAT for Raspberry Pi Hookup Guide
Get started interfacing your Qwiic enabled boards with your Raspberry Pi. The Qwiic pHAT connects the I2C bus (GND, 3.3V, SDA, and SCL) on your Raspberry Pi to an array of Qwiic connectors.
Cryptographic Co-Processor ATECC508A (Qwiic) Hookup Guide
Learn how to use some of the standard features of the SparkFun Cryptographic Co-processor.
Looking for more inspiration? Check out some of these blog posts for ideas: