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/Simple program that blinking leds

#include "AT91SAM7S64.h"

//#include "system.h"
//#include "system.c"

//#define   BIT17       0x00020000
//#define   BIT18       0x00040000

#define   BIT17       (1<<17);
#define   BIT18       (1<<18);


//AT91PS_PMC pPMC   = AT91C_BASE_PMC;
AT91PS_PIO    p_pPio   = AT91C_BASE_PIOA;
AT91PS_PMC    p_pPMC   = AT91C_BASE_PMC;
AT91PS_USART  p_pUSART = AT91C_BASE_US0;
AT91PS_PDC    p_pPDC   = AT91C_BASE_PDC_US0;
AT91PS_MC     p_pMC    = AT91C_BASE_MC;
AT91PS_AIC    p_pAic   = AT91C_BASE_AIC;

//it's a simple delay
void Delay (unsigned long a) { while (--a!=0); }

void InitFrec(void)
{

  // Disable watchwog
  AT91C_BASE_WDTC->WDTC_WDMR= AT91C_WDTC_WDDIS;

  //Enabling the Main Oscillator:
  //SCK = 1/32768 = 30.51 uSecond
  //Start up time = 8 * 6 / SCK = 56 * 30.51 = 1,46484375 ms
 
  //AT91C_BASE_PMC->PMC_MOR = ...
  p_pPMC->PMC_MOR = (( AT91C_CKGR_OSCOUNT & (0x06 <<8) | AT91C_CKGR_MOSCEN ));
  //Wait the startup time
  while(!(p_pPMC->PMC_SR & AT91C_PMC_MOSCS));

  //Setting PLL and divider:
  //- div by 5 Fin = 3,6864 =(18,432 / 5)
  //- Mul 25+1: Fout =   95,8464 =(3,6864 *26)
  //for 96 MHz the erroe is 0.16%
  //Field out NOT USED = 0
  //PLLCOUNT pll startup time estimate at : 0.844 ms
  //PLLCOUNT 28 = 0.000844 /(1/32768)
  p_pPMC->PMC_PLLR = ((AT91C_CKGR_DIV & 3) | (AT91C_CKGR_PLLCOUNT & (28<<8)) | (AT91C_CKGR_MUL & (24<<16)));

  // Wait the startup time
  while(!(p_pPMC->PMC_SR & AT91C_PMC_LOCK));
  while(!(p_pPMC->PMC_SR & AT91C_PMC_MCKRDY));

  //Selection of Master Clock and Processor Clock
  //select the PLL clock divided by 2
  p_pPMC->PMC_MCKR = AT91C_PMC_CSS_PLL_CLK | AT91C_PMC_PRES_CLK_2 ;
  while(!(p_pPMC->PMC_SR & AT91C_PMC_MCKRDY));

}


void InitPeriphery(void) {

  /**** LED BUTTONS ****/
  //enable the clock of the PIO
  p_pPMC->PMC_PCER = 1 << AT91C_ID_PIOA;

  //LED 1
  //configure the PIO Lines corresponding to LED1
  p_pPio->PIO_PER = BIT17;    //Enable PA17
  p_pPio->PIO_OER = BIT17;    //Configure in Output
  p_pPio->PIO_SODR = BIT17;   //set reg to 1

  //LED 2
  //configure the PIO Lines corresponding to LED2
  p_pPio->PIO_PER = BIT18;    //Enable PA18
  p_pPio->PIO_OER = BIT18;    //Configure in Output
  p_pPio->PIO_SODR = BIT18;   //set reg to 1

}


int main()
{
  //Init frequency
  InitFrec();
  //Init leds
  InitPeriphery();

  // loop forever
  while(1)
  {
    p_pPio->PIO_CODR = BIT18;  //set reg to 0 (led2 on)
    p_pPio->PIO_SODR = BIT17;  //set reg to 1 (led1 off)
    Delay(800000);             //simple delay
    p_pPio->PIO_CODR = BIT17;  //set reg to 0 (led1 on)
    p_pPio->PIO_SODR = BIT18;  //set reg to 1 (led2 off)
    Delay(800000);             //simple delay
  }
}

while(1)
  {
    p_pPio->PIO_CODR = BIT18;  //set reg to 0 (led2 on)
  }