MS5803-14BA Pressure Sensor Hookup Guide
CaseyTheRobot 
Installing the Arduino Library
If this is your first time using Arduino, please review our tutorial on installing the Arduino IDE. If you have not previously installed an Arduino library, please check out our installation guide.
Libraries are collections of software functions geared towards a single purpose, such as communicating with a specific device. Arduino comes with a number of built-in libraries that help you do advanced tasks. We've written an Arduino library called the SparkFun MS5803-14BA Breakout Arduino Library that allows you to easily talk to the MS5803 sensor. This library is not included with the stock Arduino software, but don't worry, installing new libraries is easy. You can obtain these libraries through the Arduino Library Manager. Search for SparkFun MS5803 and you should be able to install the latest version. If you prefer downloading the libraries manually, you can grab them from the GitHub repository:
If you'd like to interface the MS5803 to a microcontroller other than an Arduino, the C++ source code in the library and the information in the datasheet may be helpful when writing your own code.
Once you've installed the library, restart the Arduino IDE and you should be ready to go.