3.4.1 Introduction

The CDC Host Client Driver in the MPLAB Harmony USB Host Stack allows USB Host applications to support and interact with Communications Device Class (CDC) USB devices. The CDC Host Client Driver has the following features:

• Supports CDC ACM devices
• Supports CDC device matching at both the device descriptor and interface descriptor level
• Supports composite CDC devices (multiple CDC interfaces or CDC with other device classes)
• Designed to support multi-client operation
• RTOS ready
• An event driver non-clocking application interaction model
• Allows the application to send CDC ACM commands to the device
• Supports queuing of read and write data transfers