 Standard I/O (stdio) | Common standard I/O driver that implements the stdio read and write functions on AVR and SAM devices |
  Standard serial I/O (stdio) | Common standard serial I/O management driver that implements a stdio serial interface on AVR and SAM devices |
| Compiler abstraction layer and code utilities | Compiler abstraction layer and code utilities for Cortex-M0+ based Atmel SAM devices |
 Status Codes | |
| Preprocessor - Macro Recursion | |
| Preprocessor - Macro Repeat | |
| Preprocessor - Stringize | |
| Preprocessor - Token Paste | |
| Global interrupt management | This is a driver for global enabling and disabling of interrupts |
| Deprecated interrupt definitions | |
| Atmel part identification macros | This collection of macros identify which series and families that the various Atmel parts belong to |
| AVR UC3 parts | |
| AVR XMEGA parts | |
| megaAVR parts | |
| SAM parts | |
| Generic board support | The generic board support module includes board-specific definitions and function prototypes, such as the board initialization function |
 SAM D21 Xplained Pro board | |
 Features | Symbols that describe features and capabilities of the board |
| SAM Port (PORT) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's General Purpose Input/Output (GPIO) pin functionality, for manual pin state reading and writing |
| SAM System Pin Multiplexer (SYSTEM PINMUX) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's physical I/O Pins, to alter the direction and input/drive characteristics as well as to configure the pin peripheral multiplexer selection |
| SAM System (SYSTEM) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's system relation functionality, necessary for the basic device operation |
| SAM System Clock Management (SYSTEM CLOCK) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's clocking related functions |
| SAM System Interrupt (SYSTEM INTERRUPT) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of internal software and hardware interrupts/exceptions |
| SAM Event System (EVENTS) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's peripheral event resources and users within the device, including enabling and disabling of peripheral source selection and synchronization of clock domains between various modules |
| Serial Interface (Serial) | See Quick start guide for Serial Interface service |
| SAM Serial USART (SERCOM USART) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the SERCOM module in its USART mode to transfer or receive USART data frames |
1.8.5