xtest12_2.c

来自「AT91sam7s 256 B/D example」· C语言 代码 · 共 78 行

/* ========================================================================== */
/*	     Xtest12_2.c : Variable Duty Cycle of PWM0, PWM1 Output	      */
/* ========================================================================== */
/*			  Designed and programmed by Duck-Yong Yoon in 2007.  */

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

void LCD_3d(unsigned int number)		/* display 3-digit decimal number */
{ unsigned int i, flag;

  flag = 0;
  i = number/100;				// 10^2
  if(i == 0) LCD_data(' ');
  else {     LCD_data(i + '0');
             flag = 1;
       }

  number = number % 100;			// 10^1
  i = number/10;
  if((i == 0) && (flag == 0))
             LCD_data(' ');
  else {     LCD_data(i + '0');
             flag = 1;
       }

  i = number % 10;				// 10^0
  LCD_data(i + '0');
}

__inline void AT91F_PWMC_CfgMode(
        AT91PS_PWMC pPWM,			// pointer to a PWM controller
        unsigned int mode)			// PWM_MR register value
{
	pPWM->PWMC_MR = mode;
}

int main(void)
{
  unsigned int PWM0_duty = 10, PWM1_duty = 20;	// initial PWM duty value

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

  LCD_string(0x80,"PWM0 = 2kHz, 10%");		// display title
  LCD_string(0xC0,"PWM1 = 1kHz, 10%");
  Beep();

  AT91F_PWMC_CfgPMC();				// enable clock of PWMC
  AT91F_PIO_CfgPeriph(AT91C_BASE_PIOA, AT91C_PA1_PWM1 | AT91C_PA0_PWM0, 0);
  						// PWM1,PWM0 output(Peripheral A)

  AT91F_PWMC_CfgMode(AT91C_BASE_PWMC, 0x031E031E); // CLKA=CLKB = 48MHz/8/30 = 200kHz
  AT91F_PWMC_CfgChannel(AT91C_BASE_PWMC, 0, 0x020B, 100, PWM0_duty); // CLKA/100 = 2kHz
  AT91F_PWMC_CfgChannel(AT91C_BASE_PWMC, 1, 0x020B, 200, PWM1_duty); // CLKA/200 = 1kHz
  AT91F_PWMC_StartChannel(AT91C_BASE_PWMC, AT91C_PWMC_CHID1 | AT91C_PWMC_CHID0);
						// start PWM1 and PWM0

  while(1)
    { switch(Key_input())
        { case 1 : if(PWM0_duty < 90)  PWM0_duty += 10; // increment PWM0 duty by 10%
                   else                PWM0_duty = 10;
                   AT91F_PWMC_UpdateChannel(AT91C_BASE_PWMC, 0, PWM0_duty);
                   LCD_command(0x8C);
                   LCD_3d(PWM0_duty*100/100);
                   break;
          case 2 : if(PWM1_duty < 180) PWM1_duty += 20; // increment PWM1 duty by 10%
                   else                PWM1_duty = 20;
                   AT91F_PWMC_UpdateChannel(AT91C_BASE_PWMC, 1, PWM1_duty);
                   LCD_command(0xCC);
                   LCD_3d(PWM1_duty*100/200);
                   break;
        }
    }
}