一、实验接线图

二、案例程序

c语言

#include <wiringPi.h>
#include <softPwm.h>
#include <stdio.h>

#define uchar unsigned char

#define LedPinRed    0
#define LedPinGreen  1
#define LedPinBlue   2

void ledInit(void)
{
	softPwmCreate(LedPinRed,  0, 100);
	softPwmCreate(LedPinGreen,0, 100);
	softPwmCreate(LedPinBlue, 0, 100);
}

void ledColorSet(uchar r_val, uchar g_val, uchar b_val)
{
	softPwmWrite(LedPinRed,   r_val);
	softPwmWrite(LedPinGreen, g_val);
	softPwmWrite(LedPinBlue,  b_val);
}

int main(void)
{
	int i;

	if(wiringPiSetup() == -1){ //when initialize wiring failed, print message to screen
		printf("setup wiringPi failed !");
		return 1; 
	}
	//printf("linker LedPin : GPIO %d(wiringPi pin)\n",LedPin); //when initialize wiring successfully,print message to screen

	ledInit();

	while(1){
		ledColorSet(0xff,0x00,0x00);   //red	
		delay(500);
		ledColorSet(0x00,0xff,0x00);   //green
		delay(500);
		ledColorSet(0x00,0x00,0xff);   //blue
		delay(500);

		ledColorSet(0xff,0xff,0x00);   //yellow
		delay(500);
		ledColorSet(0xff,0x00,0xff);   //pick
		delay(500);
		ledColorSet(0xc0,0xff,0x3e);
		delay(500);

		ledColorSet(0x94,0x00,0xd3);
		delay(500);
		ledColorSet(0x76,0xee,0x00);
		delay(500);
		ledColorSet(0x00,0xc5,0xcd);	
		delay(500);

	}

	return 0;
}

python

#!/usr/bin/env python
import RPi.GPIO as GPIO
import time

colors = [0xFF0000, 0x00FF00, 0x0000FF, 0xFFFF00, 0xFF00FF, 0x00FFFF]
R = 11
G = 12
B = 13

def setup(Rpin, Gpin, Bpin):
	global pins
	global p_R, p_G, p_B
	pins = {'pin_R': Rpin, 'pin_G': Gpin, 'pin_B': Bpin}
	GPIO.setmode(GPIO.BOARD)       # Numbers GPIOs by physical location
	for i in pins:
		GPIO.setup(pins[i], GPIO.OUT)   # Set pins' mode is output
		GPIO.output(pins[i], GPIO.HIGH) # Set pins to high(+3.3V) to off led
	
	p_R = GPIO.PWM(pins['pin_R'], 2000)  # set Frequece to 2KHz
	p_G = GPIO.PWM(pins['pin_G'], 1999)
	p_B = GPIO.PWM(pins['pin_B'], 5000)
	
	p_R.start(100)      # Initial duty Cycle = 0(leds off)
	p_G.start(100)
	p_B.start(100)

def map(x, in_min, in_max, out_min, out_max):
	return (x - in_min) * (out_max - out_min) / (in_max - in_min) + out_min

def off():
	for i in pins:
		GPIO.output(pins[i], GPIO.HIGH)    # Turn off all leds

def setColor(col):   # For example : col = 0x112233
	R_val = (col & 0xff0000) >> 16
	G_val = (col & 0x00ff00) >> 8
	B_val = (col & 0x0000ff) >> 0

	R_val = map(R_val, 0, 255, 0, 100)
	G_val = map(G_val, 0, 255, 0, 100)
	B_val = map(B_val, 0, 255, 0, 100)
	
	p_R.ChangeDutyCycle(100-R_val)     # Change duty cycle
	p_G.ChangeDutyCycle(100-G_val)
	p_B.ChangeDutyCycle(100-B_val)

def loop():
	while True:
		for col in colors:
			setColor(col)
			time.sleep(1)

def destroy():
	p_R.stop()
	p_G.stop()
	p_B.stop()
	off()
	GPIO.cleanup()

if __name__ == "__main__":
	try:
		setup(R, G, B)
		loop()
	except KeyboardInterrupt:
		destroy()

三、试验成功图

四、七色LED灯