源文件pwm.c

#include "pwm.h"

// 频率 占空比 极性
void Pwm1_Init(volatile U16 frequency, volatile U16 duty, volatile U16 polar) {
   
	// 周期，单位是ms
	volatile U16 period = 1000 / frequency; //32.25ms(T=1/F=1/0.032S=1000/32ms)
//    volatile U16 PWM1P = period * 128;// 系统选择的内部低速时钟128K
	volatile U16 PWM1P = period * 24000;// 系统选择的24M
//	volatile U16 PWM1D = (PWM1P / 100) * duty;
    volatile U16 PWM1D = (PWM1P * duty )/ 100; // duty/100=PWM1D/PWM1P

	_push_(INSCON);
	INSCON &= 0xbf; // Bank0

	// 周期寄存器12位， 0x0fff=4095，周期=4095/128K=0.0319s=32ms
	// 通过周期计算PWM0Px的值，PWM0Px=period*128K/1000
	PWM1PL = PWM1P & 0xff; //PWM输出周期=[PWM1PH,PWM1PL]*PWM时钟周期 
	PWM1PH = PWM1P >> 8;

	// 占空比寄存器,0x07ff=2047
	// 计算占空比寄存器的值，PWM0Dx=周期寄存器值*duty/100
	PWM1DL = PWM1D & 0xff; 
	PWM1DH = PWM1D >> 8;
	
	if (polar == 1) {
   
			PWM1CON |= 0x40;
	} else {
   
			PWM1CON &= 0xbf;
	}
	// PWM1控制寄存器 1100_0001，使能、占空比期间输出低电平、占空比溢出后输出高电平、输出允许
	PWM1CON |= 0x81;// PWM输出周期=fosc/1(不分频)
	_pop_(INSCON);
}

void set_pwm_init(){
   
	
//unsigned char	SYSCLK	= 24; // 24MHz

//unsigned char PWM1CONINIT0 = 0x00;
//unsigned char PWM1CLKINIT = 0x01;
//	
//unsigned long PWM1FREQINIT = 1000 ;// PWM输出频率 1000hz
#define PWM1DUTYINIT0 90  // PWM占空比
//unsigned char PWM1DUTYINIT0;
//