# Appendix A: Glossary

The embedded ecosystem is full of different protocols, hardware components and vendor-specific things that use their own terms and abbreviations. This Glossary attempts to list them with pointers for understanding them better.

Term         | Meaning
-------------|--------
I2C          | Sometimes referred to as `I² C` or Inter-IC. It is a protocol meant for hardware communication within a single integrated circuit. See [i2c.info] for more details
SPI          | Serial Peripheral Interface
USART        | Universal synchronous and asynchronous receiver-transmitter
UART         | Universal asynchronous receiver-transmitter
FPU          | Floating-point Unit. A 'math processor' running only operations on floating-point numbers
PAC          | Peripheral Access Crate

[i2c.info]: https://i2c.info/
