dirtwillfly 发表于 2014-8-22 10:50 
launchpad的IO比较容易受到外部干扰。
但不清楚是怎么影响到你的呼吸灯的
程序如下:
#include "msp430g2553.h"
unsigned int rate=10;
unsigned char updown = 1;
void main(void) {
WDTCTL = WDT_ADLY_16; // WDT 16ms, ACLK, interval timer
BCSCTL1 = CALDCO_8MHZ; // Set range
DCOCTL = CALDCO_8MHZ; // Set DCO step + modulation
P1DIR |= BIT0 | BIT6;
P1SEL |= BIT6;
P1OUT = 0;
CCR0 = 128; // PWM Period
CCTL1 = OUTMOD_6; // CCR1 reset/set
CCR1 = rate; // CCR1 PWM duty cycle
TACTL = TASSEL_1 + MC_1; // ACLK, up mode
IE1 |= WDTIE;
_BIS_SR(LPM3_bits + GIE);
while(1);
}
#pragma vector=WDT_VECTOR
__interrupt void interrupt_watchdog_timer(void){
CCR1 = rate;
if(updown){
rate += 3;
if(rate >= 120){
updown = 0;
}
}else{
rate -= 3;
if(rate <= 10){
updown = 1;
}
}
}
是要把IO口调成输出吗,怎样写?
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