xtest14_4.c

AT91sam7s 256 B/D example

/* ========================================================================== */
/*	     Xtest14_4.c : RS-232C Communication by DBGU Polling(2)	      */
/* ========================================================================== */
/*			  Designed and programmed by Duck-Yong Yoon in 2007.  */

#include "AT91SAM7S256.h"
#include "lib_AT91SAM7S256.h"
#include "OK7S256ads.h"

unsigned int DBGU_check_RXRDY(void)		/* check RXRDY of DBGU */
{
  return *AT91C_DBGU_CSR & 0x0001;		// if RXRDY=1, return 1
}						// if not, return 0

unsigned int DBGU_RX_char(void)			/* receive a character by DBGU */
{
  while(!(*AT91C_DBGU_CSR & 0x0001));		// wait until RXRDY=1

  return *AT91C_DBGU_RHR;			// receive a character
}

void DBGU_TX_char(unsigned int data)		/* transmit a character by DBGU */
{
  while(!(*AT91C_DBGU_CSR & 0x0002));		// wait until TXRDY=1

  *AT91C_DBGU_THR = data;			// transmit a character
}

void DBGU_string(char *string)			/* transmit a string by DBGU */
{
  while(*string != '\0')
    { DBGU_TX_char(*string);
       string++;
    }
}

int main(void)
{
  unsigned int cursor;

  MCU_initialize();				// initialize AT91SAM7S256 & kit
  Delay_ms(50);					// wait for system stabilization
  LCD_initialize();				// initialize text LCD

  LCD_string(0x80," RS-232C (DBGU) ");		// display title
  LCD_string(0xC0,"                ");
  Beep();

  LCD_command(0x0F);                            // cursor ON
  LCD_command(0xC0);                            // initial cursor position
  cursor = 0;

  AT91F_DBGU_CfgPMC();				// enable clock of DBGU
  AT91F_DBGU_CfgPIO();				// DTXD, DRXD by Peripheral A

  *AT91C_DBGU_MR = 0x00000800;			// normal mode, no parity
  *AT91C_DBGU_BRGR = 26;			// MCK/16/26 = 115200 bps
  *AT91C_DBGU_CR = 0x00000150;			// TX, RX enable

  while(1)
    { switch(Key_input())                       // key input
        { case 1 : LED_on(LED1); LED_off(LED2);	// KEY1 ?
                   DBGU_string("  KEY1 is OK !  ");
                   DBGU_TX_char(0x0D);
                   DBGU_TX_char(0x0A);
                   break;
          case 2 : LED_on(LED2); LED_off(LED1);	// KEY2 ?
                   DBGU_string("  KEY2 is OK !  ");
                   DBGU_TX_char(0x0D);
                   DBGU_TX_char(0x0A);
                   break;
          default: break;
        }

      if(DBGU_check_RXRDY() == 1)
        { LCD_data(DBGU_RX_char());		// display a received character
          cursor++;                             // 16 character OK ?
          if(cursor == 16)
            { LCD_command(0xC0);                // if yes, go home
              cursor = 0;
              Beep();
            }
        }
    }
}