USB Libraries Help > USB Device Libraries > USB Device Layer Library > Using the Library > Library Overview
MPLAB Harmony USB Stack
Library Overview

The Device Layer Library provides API routines which allow the Harmony System module, function driver and the user application to interact with it. 

The library interface routines can be classified as shown in the table below  

Library Interface Section 
Description 
System Interaction Functions 
These functions allow the Harmony System Module to perform library initialization, deinitialization, reinitialization and task functions. 
Client Core Functions 
These functions allow the application client to a register an event callback function. 
Device Power State Management Functions 
These functions manage the power state of the device (self or bus powered) and remote wake-up. 
Endpoint Management Functions 
These functions allow the application to manage (enable, disable and stall) endpoints. These are required in case of a Generic or a Vendor USB Device Implementation. 
Device Management Functions 
These functions allow the application to manage (attach, detach etc.) the state of the device. 
Control Transfer Functions 
These functions allow the application to complete control transfers.