using PWM to control RGB LED for RedBear Demo
Diff: ChainableLED.cpp
- Revision:
- 0:22cae1dee34b
diff -r 000000000000 -r 22cae1dee34b ChainableLED.cpp --- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/ChainableLED.cpp Mon Apr 11 04:19:53 2016 +0000 @@ -0,0 +1,113 @@ +/* + * Copyright (C) 2013 Seeed Technology Inc. + * Copyright (C) 2012 Paulo Marques (pjp.marques@gmail.com) + * + * Permission is hereby granted, free of charge, to any person obtaining a copy of + * this software and associated documentation files (the "Software"), to deal in + * the Software without restriction, including without limitation the rights to + * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of + * the Software, and to permit persons to whom the Software is furnished to do so, + * subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in all + * copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS + * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR + * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER + * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. + */ + +/* Information about the P9813 protocol obtained from: + * http://www.seeedstudio.com/wiki/index.php?title=Twig_-_Chainable_RGB_LED + * + * HSB to RGB routine adapted from: + * http://mjijackson.com/2008/02/rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript + * + * This library is ported from Arduino to mbed + */ + + +// -------------------------------------------------------------------------------------- + +#include "ChainableLED.h" + +// Forward declaration +float hue2rgb(float p, float q, float t); +PwmOut PWMR(P0_11); +PwmOut PWMG(P0_9); +PwmOut PWMB(P0_10); +// -------------------------------------------------------------------------------------- + +ChainableLED::ChainableLED(PinName r_pin, PinName g_pin, PinName b_pin,unsigned int number_of_leds) : + _r_pin(r_pin), _g_pin(g_pin),_b_pin(b_pin) +{ + _num_leds = number_of_leds; + + + for (uint8_t i=0; i<_num_leds; i++) + setColorRGB(i, 0, 0, 0); +} + +ChainableLED::~ChainableLED() +{ +} + +// -------------------------------------------------------------------------------------- + + + +void ChainableLED::sendColor(uint8_t red, uint8_t green, uint8_t blue) +{ + //control the RGB LED by PWM + PWMR = (float)red/255; + PWMG = (float)green/255; + PWMB = (float)blue/255; + +} + +void ChainableLED::setColorRGB(unsigned int led, float red, float green, float blue) +{ + sendColor(0xff-red, 0xff-green, 0xff-blue ); +} + +void ChainableLED::setColorHSB(unsigned int led, float hue, float saturation, float brightness) +{ + float r, g, b; + + if(saturation == 0.0) + { + r = g = b = brightness; + } + else + { + float q = brightness < 0.5 ? + brightness * (1.0 + saturation) : brightness + saturation - brightness * saturation; + float p = 2.0 * brightness - q; + r = hue2rgb(p, q, hue + 1.0/3.0); + g = hue2rgb(p, q, hue); + b = hue2rgb(p, q, hue - 1.0/3.0); + } + + setColorRGB(led, (uint8_t)(255.0*r), (uint8_t)(255.0*g), (uint8_t)(255.0*b)); +} + +// -------------------------------------------------------------------------------------- + +float hue2rgb(float p, float q, float t) +{ + if (t < 0.0) + t += 1.0; + if(t > 1.0) + t -= 1.0; + if(t < 1.0/6.0) + return p + (q - p) * 6.0 * t; + if(t < 1.0/2.0) + return q; + if(t < 2.0/3.0) + return p + (q - p) * (2.0/3.0 - t) * 6.0; + + return p; +}