Modules

Here is a list of all modules:

Register Declarations	The baseline feature of this library: declarations for all documented and various undocumented hardware registers
General-Purpose I/O (GPIO)	Helper functions for configuring and accessing GPIO pins
System Timer	Utility functions for measuring time and busy-waiting short amounts of time
SPI Master (SPI0)	These functions allow direct access to the Raspberry Pi's SPI0 master peripheral without using the regular Linux device driver
SPI Slave (via IIS/PCM)	These functions allow the Raspberry Pi to act as SPI slave, even though it has some serious limitations
Asynchronous Serial Interface (UART0)	These functions allow direct access to the Raspberry Pi's UART (RS-232) controller without using the regular Linux device driver