AT90USBxxx CDC demonstration
Use of this program is subject to Atmel's End User License Agreement.
Please read file lic_page for copyright notice.
This embedded application source code illustrates how to implement a CDC application with the AT90USBxxx controller.
The sample code is delivered for STK526.
This application will enumerates as a CDC (communication device class) virtual COM port. The application can be used as a USB to serial converter.
This source code is usable with the following compilers:
- IAR Embedded Workbench (5.11A and higher)
- AVRGCC (WinAVR 20080411 and higher).
Support for other compilers may required modifications or attention for:
- compiler.h file
- special registers declaration file
- interrupt subroutines declarations
As illustrated in the figure bellow, the application entry point is located is the main.c file. The main function first performs the initialization of a scheduler module and then runs it in an infinite loop. The scheduler is a simple infinite loop calling all its tasks defined in the conf_scheduler.h file. No real time schedule is performed, when a task ends, the scheduler calls the next task defined in the configuration file (conf_scheduler.h).
The sample dual role application is based on two different tasks:
- The usb_task (usb_task.c associated source file), is the task performing the USB low level enumeration process in device mode.
- The cdc task performs the loop back application between USB and USART interfaces.
Generated on Fri Sep 11 14:25:27 2009 for ATMEL by
1.5.3