main.c

很好的资料

//*----------------------------------------------------------------------------
//*         ATMEL Microcontroller Software Support  -  ROUSSET  -
//*----------------------------------------------------------------------------
//* The software is delivered "AS IS" without warranty or condition of any
//* kind, either express, implied or statutory. This includes without
//* limitation any warranty or condition with respect to merchantability or
//* fitness for any particular purpose, or against the infringements of
//* intellectual property rights of others.
//*----------------------------------------------------------------------------
//* File Name           : main.c
//* Object              : main application written in C
//* Creation            : JPP   16/Jun/2004
//*----------------------------------------------------------------------------

// Include Standard files
#include "Board.h"

/* Global variables */
#define SPEED 		(MCKKHz/10)
unsigned int LedSpeed = SPEED *50 ;
const int led_mask[8]= {LED1, LED2, LED3, LED4};

//*--------------------------------------------------------------------------------------
//* Function Name       : change_speed
//* Object              : Adjust "LedSpeed" value depending on SW1 and SW2 are pressed or not
//* Input Parameters    : none
//* Output Parameters   : Update of LedSpeed value.
//*--------------------------------------------------------------------------------------
void change_speed ( void )
{//* Begin
    if ( (AT91F_PIO_GetInput(AT91C_BASE_PIOA) & SW1_MASK) == 0 )
    {
        if ( LedSpeed > SPEED ) LedSpeed -=SPEED ;
    }
    if ( (AT91F_PIO_GetInput(AT91C_BASE_PIOA) & SW3_MASK) == 0 )
    {
        if ( LedSpeed < MCK ) LedSpeed +=SPEED ;
    }
}//* End

//*--------------------------------------------------------------------------------------
//* Function Name       : wait
//* Object              : Software waiting loop
//* Input Parameters    : none. Waiting time is defined by the global variable LedSpeed.
//* Output Parameters   : none
//*--------------------------------------------------------------------------------------
void wait ( void )
{//* Begin
    unsigned int waiting_time ;
    change_speed () ;
    for(waiting_time = 0; waiting_time < LedSpeed; waiting_time++) ;
}//* End

//*--------------------------------------------------------------------------------------
//* Function Name       : Main
//* Object              : Software entry point
//* Input Parameters    : none.
//* Output Parameters   : none.
//*--------------------------------------------------------------------------------------
int main()
{//* Begin
    int i;
    // First, enable the clock of the PIO
       AT91F_PMC_EnablePeriphClock ( AT91C_BASE_PMC, 1 << AT91C_ID_PIOA ) ;

    // then, we configure the PIO Lines corresponding to LED1 to LED4
    // to be outputs. No need to set these pins to be driven by the PIO because it is GPIO pins only.
       AT91F_PIO_CfgOutput( AT91C_BASE_PIOA, LED_MASK ) ;

    // Clear the LED's. On the EB55 we must apply a "1" to turn off LEDs
       AT91F_PIO_SetOutput( AT91C_BASE_PIOA, LED_MASK ) ;

    // Loop forever
    for (;;)
    {
        // Once a Shot on each led
	for ( i=0 ; i < NB_LEB ; i++ )
        {
	    AT91F_PIO_ClearOutput( AT91C_BASE_PIOA, led_mask[i]) ;
	    wait();
	    AT91F_PIO_SetOutput( AT91C_BASE_PIOA, led_mask[i] ) ;
	    wait();
        }// End for
        // Once a Shot on each led
        for ( i=(NB_LEB-1) ; i >= 0 ; i-- )
        {
	    AT91F_PIO_ClearOutput( AT91C_BASE_PIOA, led_mask[i]) ;
	    wait();
	    AT91F_PIO_SetOutput( AT91C_BASE_PIOA, led_mask[i] ) ;
	    wait();
        }
    }// End for
}//* End