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:
OpenLog Artemis Hookup Guide
How to use and re-program the OpenLog Artemis, an open source datalogger. The OLA comes preprogrammed to automatically log data. The OLA can also record serial data, analog voltages, or readings from external Qwiic-enabled I2C devices. Some of these Qwiic-enabled devices include GPS/GNSS modules, pressure, altitude, humidity, temperature, air quality, environment, distance, and weight sensors.
GNSS Receiver Breakout - MAX-M10S (Qwiic) Hookup Guide
Get started using the SparkFun GNSS Receiver Breakout - MAX-M10S (Qwiic), a ultra-low power, GNSS receiver module for your asset tracking needs!
SparkFun RTK Reference Station Hookup Guide
Setup the RTK Reference Station in minutes and start sending RTCM NTRIP corrections to your favourite caster.
Looking for more inspiration? Check out some of these blog posts for ideas: