main.cpp

00001 /*
00002 ***************************************************
00003 * Code ported from http://saikoled.com            *
00004 * Licensed under GPL3                             *
00005 * Created 14 February 2013                        *
00006 * Original MCU board : Arduino Leonardo           *
00007 * Original CPU       : ATmega32u4                 *
00008 * Copyright 2013, Brian Neltner                   *
00009 ***************************************************
00010 
00011 Sources
00012 -------
00013 https://github.com/saikoLED/MyKi/blob/master/myki_16_bit_random_fade/myki_16_bit_random_fade.ino
00014 https://github.com/saikoLED/MyKi/blob/master/myki_16_bit_fade/myki_16_bit_fade.ino
00015 Above files are combined into this file using defines.
00016 
00017 http://blog.saikoled.com/post/44677718712/how-to-convert-from-hsi-to-rgb-white
00018 
00019 Other demos : Psychadelic demo
00020 DO NOT TRY THIS IF YOU ARE EPILEPTIC! THESE FREQUENCIES ARE EVEN WORSE THAN MOST STROBING LIGHTS!
00021 http://blog.saikoled.com/post/45760195354/generating-vivid-geometric-hallucinations-using-flicker
00022 
00023 This software implements 4x 16-bit PWM with a filtered fading algorithm
00024 in HSI color space and HSI -> RGBW conversion to allow for better
00025 pastel color.
00026 */
00027   
00028 #include "mbed.h"
00029 #include "hsi2rgbw_pwm.h"
00030 
00031 #define RANDOM_FADE       // Disable this define to set Normal fade.
00032 
00033 // Constants
00034 #define steptime        1       // Color transition time in ms.
00035 #define maxsaturation   1.0
00036 
00037 #ifdef RANDOM_FADE
00038     #define propgain        0.0005 // "Small Constant"
00039     #define minsaturation   0.9
00040 #else
00041     #define hue_increment   0.01
00042 #endif
00043 
00044 Serial pc(USBTX, USBRX);
00045 
00046 // HSI to RGBW conversion with direct output to PWM channels
00047 hsi2rgbw_pwm led(LED_RED, LED_GREEN, LED_BLUE);
00048 
00049 struct HSI {
00050     float h;
00051     float s;
00052     float i;
00053 #ifdef RANDOM_FADE
00054     float htarget;
00055     float starget;
00056 #endif
00057 } color;
00058 
00059 void updatehue() {
00060 #ifdef RANDOM_FADE
00061     color.htarget += ((rand()%360)-180)*.1;
00062     color.htarget = fmod(color.htarget, 360);
00063     color.h += propgain*(color.htarget-color.h);
00064     color.h = fmod(color.h, 360);
00065 #else
00066     color.h = color.h + hue_increment;
00067     if(color.h > 360)
00068         color.h = 0;
00069 #endif
00070 }
00071 
00072 void updatesaturation() {
00073 #ifdef RANDOM_FADE
00074     color.starget += ((rand()%10000)-5000)/0.00001;
00075     if (color.starget > maxsaturation) color.starget = maxsaturation;
00076     else if (color.starget < minsaturation) color.starget = minsaturation;
00077     color.s += propgain*(color.starget-color.s);
00078     if (color.s > maxsaturation) color.s = maxsaturation;
00079     else if (color.s < minsaturation) color.s = minsaturation;
00080 #else
00081     color.s = maxsaturation;
00082 #endif
00083 }
00084 
00085 void primary_colors() {
00086     printf("briefly show RED - GREEN - BLUE using hsi2rgbw.\r\n");
00087     color.s = 1;
00088     color.i = 1;
00089     for (color.h = 0 ; color.h < 360 ; color.h += 120)
00090     {
00091         led.hsi2rgbw(color.h, color.s, color.i);
00092         wait(1);
00093     }
00094 }
00095 
00096 void cycle_rgbw() {
00097     float rgbw[4] = {0,0,0,0};
00098     color.s = 1;
00099     color.i = 1;
00100     printf("briefly show RED - GREEN - BLUE using direct PWM output.\r\n");
00101     rgbw[0] = 1.0f;
00102     led.pwm(rgbw);
00103     wait(1);
00104     rgbw[0] = 0.0f;
00105     rgbw[1] = 1.0f;
00106     led.pwm(rgbw);
00107     wait(1);
00108     rgbw[1] = 0.0f;
00109     rgbw[2] = 1.0f;
00110     led.pwm(rgbw);
00111     wait(1);
00112 }
00113 
00114 void sendcolor() {
00115     while (color.h >=360) color.h = color.h - 360;
00116     while (color.h < 0) color.h = color.h + 360;
00117     if (color.i > 1) color.i = 1;
00118     if (color.i < 0) color.i = 0;
00119     if (color.s > 1) color.s = 1;
00120     if (color.s < 0) color.s = 0;
00121     // Fix ranges (somewhat redundantly).
00122     led.hsi2rgbw(color.h, color.s, color.i);
00123 }
00124  
00125  void setup()  {
00126     led.invertpwm(1); //KL25Z RGB LED uses common anode.
00127     color.h = 0;
00128     color.s = maxsaturation;
00129     color.i = 0;
00130 #ifdef RANDOM_FADE
00131     color.htarget = 0;
00132     color.starget = maxsaturation;
00133 #endif
00134   
00135     // Initial color = off, hue of red fully saturated.
00136     while (color.i < 1) {
00137         sendcolor();
00138         color.i = color.i + 0.001; // Increase Intensity
00139         updatehue();
00140         updatesaturation();
00141         wait_ms(steptime);
00142     }
00143 }
00144 
00145 int main()  {
00146     pc.baud (115200);
00147     printf("HSI to RGB random fade.\r\n");
00148     printf("Initialize.\r\n");
00149 
00150     setup();
00151     primary_colors();
00152     cycle_rgbw();
00153     printf("Run.\r\n");
00154     while(1) {
00155         sendcolor();
00156         updatehue();
00157         updatesaturation();
00158         wait_ms(steptime);
00159     }
00160 }