CDC class
The communitcation device class is primarily used and supported by modems, ISDN and also by fax machines.
Overview
The USB Communications Device Class (CDC) provides access to COM port devices via USB. This enables communication via modems for mobile networks such as GSM/3G/LTE or cable based network modems. Any device which uses CDC for configuration and data transmission, such as a point-of-sale terminal, can be accessed via the CDC class driver as well.
Key features
- Compatibility with different CDC devices
- Ability to send and receive data
- Ability to set various parameters, such as baud rate, number of stop bits, parity
- Handling of multiple CDC devices at the same time
- Notifications about CDC connection status
- Ability to query the CDC line and modem status
- Small memory footprint in RAM and ROM
Requirements
Components required to use emUSB-Host CDC:
- emUSB-Host CDC (Included in emUSB-Host PRO package)
- emUSB-Host core (Included in emUSB-Host PRO package)
- emUSB-Host target driver (One driver is included in emUSB-Host PRO package)
- Real-time operating system (embOS or other)
Example Code Included
An example application which uses the API is provided with any shipment or eval software including emUSB-Host. This example displays information about the CDC device in the I/O terminal of the debugger. In addition the application then starts a simple echo server, sending back the received data. Several application samples can also be found on the emUSB-Host sample page.
