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cc2540的PWM输出问题

我正在调试cc2540的Timer1,用通道1,2,3,4来输出PWM波,并且可以实时改变占空比。通道1和2(即P03,P04口)输出正常,可以实现变比。但是通道3和4(即P05,P06口)无法正常输出,有两个问题:1,无法实时改变占空比(不是我改占空比的程序问题),2,P05最高输出2.5V。不知道这是为什么。附上我的相关程序段,希望老师们可以帮忙解决!谢谢!

#define MODE_2              0x02     //0x0000 -> T1CC0

#define SET0_REn 0x30 //set when cc0, clear when ccn

#define CLR_IM 0x00 //IM = 0

#define CLR 0x00

#define RFIRQ 0x80 //When set, use RF interrupt for capture instead of regular capture input.

#define IM 0x40 //Channel 0 interrupt mask. Enables interrupt request when set.

#define CLR_Output 0x08 //Clear output on compare

void InitIO(void) {

    P0DIR |= BIT3 + BIT4 + BIT5 + BIT6; 

    P0SEL |= BIT3 + BIT4 + BIT5 + BIT6;

}

void InitT1() {

     InitIO();

     PERCFG |= 0x03;

     T1CTL |= DIV_128 + MODE_2; //128分频,模式2

     T1CCTL1 |= CLR_IM + Compare_Mode + SET0_REn;// IM = 0;set when cc0, clear when ccn; Mode = Compare

     T1CCTL2 |= CLR_IM + Compare_Mode + SET0_REn;// IM = 0;set when cc0, clear when ccn; Mode = Compare

     T1CCTL3 |= CLR_IM + Compare_Mode + SET0_REn;// IM = 0;set when cc0, clear when ccn; Mode = Compare

     T1CCTL4 |= CLR_IM + Compare_Mode + SET0_REn;// IM = 0;set when cc0, clear when ccn; Mode = Compare

     T1CNTL = 0; // Reset timer to 0;

     T1CCTL0 |= IM + CLR_Output + Compare_Mode;//0x4c

     T1CC0L = 0xE8;

     T1CC0H = 0x03; //计数1000次,即PWM周期为1000

     T1CC1L = (char)500; T1CC1H = 500>>8;

     T1CC2L = (char)500; T1CC2H = 500>>8;

     T1CC3L = (char)500; T1CC3H = 500>>8;

     T1CC4L = (char)500; T1CC4H = 500>>8;

     EA = Start; //开总中断

     IEN1 |= T1IE; //开定时器1中断

}

void Change_duty(int LF, int RF, int LB, int RB) {

    T1CC1L = (char)LF; T1CC1H = (char)(LF >> 8);

   T1CC2L = (char)RF;    T1CC2H = (char)(RF >> 8);

   T1CC3L = (char)LB;    T1CC3H = (char)(LB >> 8);

   T1CC4L = (char)RB;    T1CC4H = (char)(RB >> 8);

 }

#pragma vector = T1_VECTOR

__interrupt void T1_ISR(void) {

    EA = 0;

   unsigned char flag = T1STAT;

   Count_Period++;

   if(flag&CH0IF && Count_Period >= Sample_Period) {

   Count_Period = 0;

   get_DMP();

   PID();

   Change_duty(PWM_LF,PWM_RF,PWM_LB,PWM_RB); }

   T1STAT = ~flag;

   EA = 1;

}

cedar_xuesong:

https://github.com/cedar-renjun/RemoteControl-Car

参考我的开源代码,4个通道都可以用

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