Introduction
1 USB Device Stack Acronyms and Abbreviations
This section describes commonly used acronyms and abbreviations throughout this document, ordered by first appearance.
2 USB Device Stack Architecture
3 User Guide
- 3.1 USB Stack Handling
- 3.2 HID Overview
- 3.3 HID - How to use
- 3.4 HID Mouse - How to use
- 3.5 HID Keyboard - How to use
- 3.6 CDC Overview
- 3.7 USB CDC - How to use
  The USB CDC class implementation handles basic CDC requests and mainly consists of a handler function and several helper functions to access status variables transmitted to and from the host.
- 3.8 CDC: Virtual Serial Port - How to use
  The USB CDC Class Virtual Serial Port (VSP) implementation handles setup for serial communication over USB. It consists of a handler function and helper functions to access and transmit data.
- 3.9 Vendor Overview
- 3.10 Vendor - How to use
4 USB Device Stack API Documentation
5 Document Revision History
Microchip Information

3.6 CDC Overview

The USB Stack’s Communication Device Class (CDC) implementation allows the user to perform a variety of networking and communication operations, and it is possible to extend the compatibility by writing drivers to support devices such as digital telephones or cable modems through the usage of the USB stack. With the ability to function as a virtual COM port, with an easy-to-use function set, CDC can be preferable to other standards. The internal USB and CDC solution can replace external USART → CDC translation hardware when implemented.

The USB CDC capabilities allows for certain benefits, such as:

Can appear as a virtual COM port on PC-side applications
Reliable data transfer through protocol-level error handling, data buffering, automatic flow control etc.
Supports Abstract Control Model (ACM) functionality
Supports multiple OS, including Windows, macOS and Linux
Hardware indiscriminate protocol

The online versions of the documents are provided as a courtesy. Verify all content and data in the device’s PDF documentation found on the device product page.