用ASF跑SAMD21程序(6)USART-BASIC

/**

 * \file

 *

 * \brief Empty user application template

 *

 */



/**

 * \mainpage User Application template doxygen documentation

 *

 * \par Empty user application template

 *

 * This is a bare minimum user application template.

 *

 * For documentation of the board, go \ref group_common_boards "here" for a link

 * to the board-specific documentation.

 *

 * \par Content

 *

 * -# Include the ASF header files (through asf.h)

 * -# Minimal main function that starts with a call to system_init()

 * -# Basic usage of on-board LED and button

 * -# "Insert application code here" comment

 *

 */



/*

 * Include header files for all drivers that have been imported from

 * Atmel Software Framework (ASF).

 */

#include <asf.h>



void configure_usart(void);

struct usart_module usart_instance;



void configure_usart(void)

{   

         struct usart_config config_usart;

         usart_get_config_defaults(&config_usart);

         config_usart.baudrate    = 9600;

         config_usart.mux_setting = EDBG_CDC_SERCOM_MUX_SETTING;

         config_usart.pinmux_pad0 = EDBG_CDC_SERCOM_PINMUX_PAD0;

         config_usart.pinmux_pad1 = EDBG_CDC_SERCOM_PINMUX_PAD1;

         config_usart.pinmux_pad2 = EDBG_CDC_SERCOM_PINMUX_PAD2;

         config_usart.pinmux_pad3 = EDBG_CDC_SERCOM_PINMUX_PAD3;

         while (usart_init(&usart_instance, EDBG_CDC_MODULE, &config_usart) != STATUS_OK)

          {    }

          usart_enable(&usart_instance);

}







int main (void)

{

        system_init();

        configure_usart();

        uint8_t string[] = "Hello World!\r\n";

        usart_write_buffer_wait(&usart_instance, string, sizeof(string));

        uint16_t temp;

        while (true) 

        { 

                if (usart_read_wait(&usart_instance, &temp) == STATUS_OK)

                {            while (usart_write_wait(&usart_instance, temp) != STATUS_OK)

                                 {            }

                } 

        }

}