1 Each term should be used in one and only one way throughout the dissertation.  The easiest way to avoid a long series of definitions is to include a statement: ``the terminology used throughout this document follows that given in [CITATION].'' Then, only define exceptions.
Serial Peripheral Interface Bus. The Serial Peripheral Interface bus (SPI) is a synchronous serial communication interface specification used for short distance communication, primarily in embedded systems. The interface was developed by Motorola in the late 1980s and has become a de facto standard. Typical applications include Secure Digital cards and liquid crystal displays.
Introduced by Intel in 1992, revised in 1993 to version 2.0, and later revised in 1995 to PCI 2.1. PCI is short for Peripheral Component Interconnect and is a 32-bit computer bus that is also available as a 64-bit bus today. The PCI bus is the most commonly used and found bus in computers today. The PCI bus version 2.1