pwm_0_9.c

基于cc1010的设计实例

/*****************************************************************************
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 *      ***        ***                                                       *
 *      ***   +++   ***                                                      *
 *      ***   + +   ***                                                      *
 *      ***   +                    CHIPCON CC1010 EXAMPLE PROGRAM            *
 *      ***   + +   ***                         PWM                          *
 *      ***   +++   ***                                                      *
 *      ***       ***                                                        *
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 * Demonstrates use of the timer module as a PWM source. Uses:               *
 * - PWM2_SET_PERIOD, PWM2_SET_DUTY_CYCLE macros                             *
 * - various other HAL functions and macros                                  *
 *                                                                           *
 *****************************************************************************
 * Author:              TEL/ARR                                              *
 *****************************************************************************
 * Revision history:                                                         *
 * 1.0  2002/04/26      First Public Release                                 *
 *                                                                           *
 * $Log: pwm_0_9.C,v $
 * Revision 1.1  2002/10/14 09:45:07  tos
 * Initial version in CVS.
 *
 *                                                                           *
 ****************************************************************************/
#include <chipcon/hal.h>
#include <chipcon/cc1010eb.h>

int duty_cycle = 128;

int main(){

    // Disable watchdog timer
    WDT_ENABLE(FALSE);

    // All I/Os are inputs after reset. Make I/Os connected to LEDs outputs
    RLED=YLED=GLED=BLED=LED_OFF;
    RLED_OE(TRUE); YLED_OE(TRUE); GLED_OE(TRUE); BLED_OE(TRUE);
   
    // Switch to 32kHz clock first
    X32_INPUT_SOURCE(X32_USING_CRYSTAL);
    X32_ENABLE(TRUE);
    halWait(250, CC1010EB_CLKFREQ);
    halWait(250, CC1010EB_CLKFREQ);
    MAIN_CLOCK_SET_SOURCE(CLOCK_X32);
    XOSC_ENABLE(FALSE);

    // Configure timer 2 as a PWM timer, max timeout interval
    halConfigTimer23(TIMER2 | TIMER23_PWM, 0, CC1010EB_CLKFREQ);
    PWM2_SET_PERIOD(62); // approx 1/2 second 
    PWM2_SET_DUTY_CYCLE(duty_cycle);
    TIMER2_RUN(TRUE);

    // infinite loop
    while(1) {
        // read inputbutton
        if (SW2_PRESSED) { // button pushed - increment duty cycle
            duty_cycle+=8;
            // check that dutycycle is a valid number
            if (duty_cycle>256)
                duty_cycle = 0;
        } else if (SW3_PRESSED) { // button pushed - decrement
            duty_cycle-=8;
            // check that dutycycle is a valid number
            if (duty_cycle<0)
                duty_cycle = 256;
        } // end if
        PWM2_SET_DUTY_CYCLE(duty_cycle);
    }
   
} // end main