 Universal Synchronous Asynchronous | Receiver Transmitter (USART) |
| FLASHCALW - FLASH Controller Double-Word | See Quickstart guide for SAM FLASHCALW driver |
| Cyclic Redundancy Check Calculation Unit (CRCCU) | Driver for the Cyclic Redundancy Check Calculation Unit |
| FatFS file system service | Service of FatFS file system |
| Port of low level driver for FatFS | Low level driver for FatFS |
| Universal Synchronous Asynchronous Receiver | Transmitter (USART) |
 Compiler abstraction layer and code utilities | Compiler abstraction layer and code utilities for AT91SAM |
 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 | |
| AES - Advanced Encryption Standard module | Driver for the AES (Advanced Encryption Standard) module |
| Clock Management | |
| DFLL Management | A Digital Frequency Locked Loop can be used to generate a highly accurate frequency from a slower-running reference clock, in much the same way as a PLL |
| Generic Clock Management | Generic clocks are configurable clocks which run outside the system clock domain |
| Oscillator Management | This group contains functions and definitions related to configuring and enabling/disabling on-chip oscillators |
| PLL Management | This group contains functions and definitions related to configuring and enabling/disabling on-chip PLLs |
 System Clock Management | See Quick Start Guide for the System Clock Management service (SAM4L) |
 System Clock internals | |
| BPM - Backup Power Manager | Driver for the BPM (Backup Power Manager) |
| Sleep manager | The sleep manager is a service for ensuring that the device is not put to sleep in deeper sleep modes than the system (e.g., peripheral drivers, services or the application) allows at any given time |
| Common IOPORT API | See Quick start guide for the common IOPORT service |
| Memory Control Access | Common abstraction layer for memory interfaces |
| SAM4L Asynchronous Timer (AST) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's Asynchronous Timer functionality |
| USBC Host Driver | USBC low-level driver for USB host mode |
| SAM4L General-Purpose Input/Output (GPIO) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the on-chip General-Purpose Input/Output (GPIO) controller with both interrupt and event support |
| SAM4L External Interrupt Controller (EIC) Driver | This driver for Atmel® | SMART ARM®-based microcontrollers provides an interface for the configuration and management of the device's on-chip External Interrupt Controller (EIC) |
| USB Stack | This stack includes the USB Device Stack, USB Host Stack and common definitions |
| USB Stack Host | This module includes USB Stack Host implementation |
| USB host Controller (UHC) | The UHC provides a high-level abstraction of the usb host |
| Implementation of UHC | Internal implementation |
| USB Host Controller (UHC) - Prerequisites | Common prerequisites for all USB hosts |
| USB Host Controller (UHC) - Example code | Common example code for all USB hosts |
| USB Device Controller (UHC) - Workflow | Common workflow for all USB devices |
| USB Host Driver (UHD) | The UHD driver provides a low-level abstraction of the host controller hardware |
| USBC Host Driver | |
| USB Host Interface (UHI) | The UHI provides a common API for all classes, and this is used by UHC for the main control of USB host interface |
| UHI for Mass Storage Class | Common APIs used by high level application to use this USB host class |
| Implementation of UHI Mass Storage Class | Class internal implementation |
| USB host Mass Storage interface for control access module | Layer added on UHI MSC interface to allow the usage of control access module |
| Implementation of USB host Mass Storage | Interface for control access module |
| Interface with USB Host Core (UHC) | Define and functions required by UHC |
| USBC OTG Driver | USBC low-level driver for OTG features |
| Atmel USB Identifiers | This module defines Atmel PID and VIDs constants |
| USB Protocol Definitions | This module defines constants and data structures provided by the USB 2.0 specification |
| USB Mass Storage Class (MSC) protocol definitions | |
| SCSI Block Commands protocol definitions | |
| SCSI Primary Commands protocol definitions | |
| SAM4L-EK Board | |
| Feature definitions | |
| Generic board support | The generic board support module includes board-specific definitions and function prototypes, such as the board initialization function |
| WDT_SAM4L - SAM4L Watchdog Timer | Driver for the WDT (Watchdog Timer) |
1.8.5