摘要
这篇文章通过定时器产生PWM波，控制LED实现呼吸灯的效果，并且通过三路PWM分别控制RGB三色灯，实现了颜色渐变。最后通过调制PWM频率，使用蜂鸣器实现了音乐播放。
PWM简介
Pulse Width Modulation 翻译成中文是 脉冲宽度调制，简单的可以理解为PWM就是控制方波的频率和占空比
RGB灯渐变源代码
/*接线方法：P0.4 -- 红灯P0.5 -- 绿灯P0.6 -- 蓝灯*/#include <ioCC2530.h>//定义控制灯的端口#define LED1 P1_0 //定义LED1为P1_0口控制#define LED2 P1_5 //定义LED2为P1_5口控制#define LED3 P1_3 //定义LED3为P1_3口控制#define LED4 P1_4 //定义LED4为P1_4口控制#define SW1 P1_2 //定义SW1为P1_2端口#define SW2 P0_1 //定义SW2为P0_1端口#define SRCLK P0_4#define RCLK P0_5#define SER P0_6#define LEDS0 P0_7#define LEDS1 P1_7#define LEDS2 P0_0/****************************//延时*****************************/char pause = 0;void Delay_mS(unsigned int n){unsigned int tt,i = 0; for(i = 0; i < n; i ++)for(tt = 0; tt<1040; tt++);while(pause);}void Delay_uS(unsigned int n){unsigned int i = 0;for(;i < n; i++);}/****************************//初始化函数*****************************/void Initial(void){CLKCONCMD = 0x80; //32MHz 外部晶振P0DIR = 0xFF;P0SEL = 0xFF; //设置P0为外设功能P2DIR = 0xC0; //设置Timer外设引脚的优先级//配置工作模式和分频系数T1CTL = 0x01;T1CCTL2 = 0x24; //设置T1输出的通道2，Channel 2 T1CCTL3 = 0x24; //设置T1输出的通道3，Channel 3T1CCTL4 = 0x24; //设置T1输出的通道4，Channel 4T1CC2L = 0x10; T1CC2H = 0x00;T1CC3L = 0x10; T1CC3H = 0x00;T1CC4L = 0x10; T1CC4H = 0x00; }/***************************//主函数***************************/void main(void){unsigned short r = 60000;unsigned short g = 300;unsigned short b = 300;int stage = 1;Initial(); //调用初始化函数while(1){if(stage == 1){r -= 300;g += 300;if(g == 60000) {stage = 2;}}else if(stage == 2){g -= 300;b += 300;if(b == 60000) {stage = 3;}}else if(stage == 3){b -= 300;r += 300;if(r == 60000) {stage = 1;}}T1CC2L = r;T1CC2H = r>>8;T1CC3L = g;T1CC3H = g>>8;T1CC4L = b;T1CC4H = b>>8;Delay_mS(10);}}
音符与频率对应关系
播放音乐源代码
/*接线方法：P0.6连接蜂鸣器*/#include <ioCC2530.h>//定义控制灯的端口#define LED1 P1_0 //定义LED1为P1_0口控制#define LED2 P1_5 //定义LED2为P1_5口控制#define LED3 P1_3 //定义LED3为P1_3口控制#define LED4 P1_4 //定义LED4为P1_4口控制#define SW1 P1_2 //定义SW1为P1_2端口#define SW2 P0_1 //定义SW2为P0_1端口#define SRCLK P0_4#define RCLK P0_5#define SER P0_6#define LEDS0 P0_7#define LEDS1 P1_7#define LEDS2 P0_0/****************************//延时*****************************/char pause = 0;void Delay_mS(unsigned int n){unsigned int tt,i = 0;for(i = 0; i < n; i ++)for(tt = 0; tt<1040; tt++);while(pause);}void Delay_uS(unsigned int n){unsigned int i = 0;for(;i < n; i++);}/****************************//初始化函数*****************************/void Initial(void){CLKCONCMD = 0x88;P0DIR = 0xFF;P1DIR = 0xFB;//将P12设为输入，其他设为输出 (0xFB = 11111011)LED1 = 0;//关闭LED1LED2 = 0;//关闭LED2LED3 = 0;//关闭LED3LED4 = 0;//关闭LED4P0SEL |= 0x40; //设置P0.6为外设功能//配置工作模式和分频系数T1CTL = 0x0E;T1CCTL4 = 0x24; //设置T1通道4比较输出功能T1CC4L = 0xA; //设置T1CC4,PWM输出时比较值值T1CC4H = 0x00; }void PWM_Play(int tune, int time){if(tune == 0){P0SEL = 0x00; P0_6 = 0; Delay_mS(time);P0SEL |= 0x40; return;}T1CNTL = 0;T1CNTH = 0;T1CC0L = 125000/tune;T1CC0H = (125000/tune) >> 8;Delay_mS(time);}void birth(){PWM_Play(784,500);PWM_Play(0, 25);PWM_Play(784,500);PWM_Play(880,1000);PWM_Play(784,1000);PWM_Play(1046,1000);PWM_Play(988,2000);PWM_Play(0, 300);PWM_Play(784,500);PWM_Play(0, 25);PWM_Play(784,500);PWM_Play(880,1000);PWM_Play(784,1000);PWM_Play(1175,1000);PWM_Play(1046,2000);PWM_Play(0, 1000);}void mamahao(){PWM_Play(880,1500);PWM_Play(784,500);PWM_Play(659,1000);PWM_Play(784,1000);PWM_Play(1046,1000);PWM_Play(880,500);PWM_Play(784,500);PWM_Play(880,2000);PWM_Play(0, 1000);}/***************************//主函数***************************/void main(void){Initial(); //调用初始化函数PWM_Play(0, 100);while(1){birth()；mamahao();}}
