color_pixels.cpp

00001 /** Color pixels library using WS2812B and nRF51822 (16MHz)
00002  *  It's for
00003  *    + http://www.seeedstudio.com/depot/Digital-RGB-LED-FlexiStrip-60-LED-1-Meter-p-1666.html
00004  *    + http://www.seeedstudio.com/depot/WS2812B-Digital-RGB-LED-Waterproof-FlexiStrip-144-LEDmeter-2-meter-p-1869.html
00005  *    + http://www.seeedstudio.com/depot/WS2812B-RGB-LED-with-Integrated-Driver-Chip-10-PCs-pack-p-1675.html
00006  *
00007  * The MIT License (MIT)
00008  *
00009  * Copyright (c) 2014 Seeed Technology Inc.
00010  *
00011  * Permission is hereby granted, free of charge, to any person obtaining a copy
00012  * of this software and associated documentation files (the "Software"), to deal
00013  * in the Software without restriction, including without limitation the rights
00014  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
00015  * copies of the Software, and to permit persons to whom the Software is
00016  * furnished to do so, subject to the following conditions:
00017 
00018  * The above copyright notice and this permission notice shall be included in
00019  * all copies or substantial portions of the Software.
00020 
00021  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
00022  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
00023  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
00024  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
00025  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
00026  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
00027  * THE SOFTWARE.
00028  */
00029 
00030 #include "color_pixels.h"
00031 #include "nrf51.h"
00032 #include "nrf51_bitfields.h"
00033 
00034 #if !defined ( __GNUC__ )
00035 // Generate a high level pulse (0.81us) of WS2812B's 1 code (0.9us +- 0.15us)
00036 #define COLOR_PIXELS_ONE_HIGH(mask)     \
00037             NRF_GPIO->OUTSET = (mask);  \
00038             __ASM ( \
00039                     " NOP\n\t" \
00040                     " NOP\n\t" \
00041                     " NOP\n\t" \
00042                     " NOP\n\t" \
00043                     " NOP\n\t" \
00044                     " NOP\n\t" \
00045                     " NOP\n\t" \
00046                     " NOP\n\t" \
00047                     " NOP\n\t" \
00048                 ); \
00049             NRF_GPIO->OUTCLR = (mask)
00050 
00051 // Generate a high level pulse (0.31us) of WS2812B's 0 code (0.35us +- 0.15us)
00052 #define COLOR_PIXELS_ZERO_HIGH(mask)    \
00053             NRF_GPIO->OUTSET = (mask);  \
00054             __ASM (  \
00055                     " NOP\n\t"  \
00056                 );  \
00057             NRF_GPIO->OUTCLR = (mask);  \
00058             __ASM ( \
00059                     " NOP\n\t" \
00060                     " NOP\n\t" \
00061                     " NOP\n\t" \
00062                     " NOP\n\t" \
00063                     " NOP\n\t" \
00064                     " NOP\n\t" \
00065                     " NOP\n\t" \
00066                     " NOP\n\t" \
00067                 )
00068 #else
00069 // Generate a high level pulse (0.94us) of WS2812B's 1 code (0.9us +- 0.15us)
00070 #define COLOR_PIXELS_ONE_HIGH(mask)     \
00071             NRF_GPIO->OUTSET = (mask);  \
00072             __ASM ( \
00073                     " NOP\n\t" \
00074                     " NOP\n\t" \
00075                     " NOP\n\t" \
00076                     " NOP\n\t" \
00077                     " NOP\n\t" \
00078                     " NOP\n\t" \
00079                     " NOP\n\t" \
00080                     " NOP\n\t" \
00081                 ); \
00082             NRF_GPIO->OUTCLR = (mask)
00083 
00084 // Generate a high level pulse (0.44us) of WS2812B's 0 code (0.35us +- 0.15us)
00085 #define COLOR_PIXELS_ZERO_HIGH(mask)    \
00086             NRF_GPIO->OUTSET = (mask);  \
00087             __ASM (  \
00088                     " NOP\n\t"  \
00089                 );  \
00090             NRF_GPIO->OUTCLR = (mask);  \
00091             __ASM ( \
00092                     " NOP\n\t" \
00093                     " NOP\n\t" \
00094                     " NOP\n\t" \
00095                     " NOP\n\t" \
00096                     " NOP\n\t" \
00097                     " NOP\n\t" \
00098                     " NOP\n\t" \
00099                     " NOP\n\t" \
00100                 )
00101 #endif            
00102 
00103 static void delay_us(uint32_t us)
00104 {
00105     do {
00106         __ASM volatile (
00107             "NOP\n\t"
00108             "NOP\n\t"
00109             "NOP\n\t"
00110             "NOP\n\t"
00111             "NOP\n\t"
00112             "NOP\n\t"
00113             "NOP\n\t"
00114             "NOP\n\t"
00115             "NOP\n\t"
00116             "NOP\n\t"
00117             "NOP\n\t"
00118             "NOP\n\t"
00119         );
00120     } while (--us);
00121 }
00122 
00123 ColorPixels::ColorPixels(uint8_t pin, uint16_t num)
00124 {
00125     this->pin = pin;
00126     this->num = num;
00127 
00128     NRF_GPIO->PIN_CNF[pin] = (GPIO_PIN_CNF_SENSE_Disabled << GPIO_PIN_CNF_SENSE_Pos)
00129                              | (GPIO_PIN_CNF_DRIVE_S0S1 << GPIO_PIN_CNF_DRIVE_Pos)
00130                              | (GPIO_PIN_CNF_PULL_Disabled << GPIO_PIN_CNF_PULL_Pos)
00131                              | (GPIO_PIN_CNF_INPUT_Connect << GPIO_PIN_CNF_INPUT_Pos)
00132                              | (GPIO_PIN_CNF_DIR_Output << GPIO_PIN_CNF_DIR_Pos);
00133     NRF_GPIO->OUTCLR = (1UL << pin);
00134 
00135     colors = new grb_t[num];
00136     for (int i = 0; i < num; i++) {
00137         colors[i].grb = 0;
00138     }
00139 }
00140 
00141 ColorPixels::~ColorPixels()
00142 {
00143     delete colors;
00144 }
00145 
00146 
00147 void ColorPixels::set_color(uint16_t index, uint8_t r, uint8_t g, uint8_t b)
00148 {
00149     if (index < num) {
00150         colors[index].r = r;
00151         colors[index].g = g;
00152         colors[index].b = b;
00153     }
00154 }
00155 
00156 void ColorPixels::set_color(uint16_t index, uint32_t rgb) {
00157     color_t c = *(color_t *)&rgb;
00158     set_color(index, c.r, c.g, c.b);
00159 }
00160 
00161 void ColorPixels::set_all_color(uint8_t r, uint8_t g, uint8_t b)
00162 {
00163     for (int i = 0; i < num; i++) {
00164         colors[i].r = r;
00165         colors[i].g = g;
00166         colors[i].b = b;
00167     }
00168 
00169     update();
00170 }
00171 
00172 void ColorPixels::update()
00173 {
00174     uint32_t mask =  1 << pin;
00175     NRF_GPIO->OUTCLR = mask;
00176     delay_us(50);
00177     
00178     grb_t *pcolor = colors;
00179     for (int i = 0; i < num; i++) {
00180         uint32_t grb = (*pcolor).grb;
00181         for (int bit = 0; bit < 24; bit++) {
00182             if (grb & 1) {
00183                 COLOR_PIXELS_ONE_HIGH(mask);
00184             } else {
00185                 COLOR_PIXELS_ZERO_HIGH(mask);
00186             }
00187             grb >>= 1;
00188         }
00189         pcolor++;
00190     }
00191 }
00192 
00193 void ColorPixels::clear()
00194 {
00195     for (int i = 0; i < num; i++) {
00196         colors[i].grb = 0;
00197     }
00198 
00199     update();
00200 }
00201 
00202 uint32_t toRGB(uint8_t red, uint8_t green, uint8_t blue)
00203 {
00204     color_t c;
00205     
00206     c.r = red;
00207     c.g = green;
00208     c.b = blue;
00209     
00210     return c.rgb;
00211 };
00212 
00213 uint32_t wheel(float position, uint8_t min = 0, uint8_t max = 255) 
00214 {
00215     uint8_t d = max - min;
00216     uint32_t c;
00217 
00218     if(position < 0.166) {
00219         c = toRGB(max, min + position * 6 * d, min);
00220     } else if(position < 0.332) {
00221         position -= 0.166;
00222         c = toRGB(max - position * 6 * d, max, min);
00223     } else if(position < 0.498) {
00224         position -= 0.332;
00225         c = toRGB(min, max, min + position * 6 * d);
00226     } else if(position < 0.664) {
00227         position -= 0.498;
00228         c = toRGB(min, max - position * 6 * d, max);
00229     } else if(position < 0.83) {
00230         position -= 0.664;
00231         c = toRGB(min + d * position * 6, min, max);
00232     } else {
00233         position -= 0.83;
00234         c = toRGB(max, min, max - position * 6 * d);
00235     }
00236     
00237     return c;
00238 }
00239 
00240 void find_wheel_options(uint32_t rgb, float *position, uint8_t *min, uint8_t *max)
00241 {
00242     color_t c;
00243     c.rgb = rgb;
00244     
00245     if (c.r > c.g) {
00246         if (c.g >= c.b) {
00247             *max = c.r;
00248             *min = c.b;
00249             *position = (float)(c.g - c.b) / (c.r - c.b) / 6.0;
00250         } else if (c.b >= c.r) {
00251             *max = c.b;
00252             *min = c.g;
00253             *position = (float)(c.r - c.g) / (c.b - c.g) / 6.0 + 0.664;
00254         } else {
00255             *max = c.r;
00256             *min = c.g;
00257             *position = (float)(c.b - c.g) / (c.r - c.g) / 6.0 + 0.83;
00258         }
00259     } else {
00260         if (c.r > c.b) {
00261             *max = c.g;
00262             *min = c.b;
00263             *position = (float)(c.r - c.b) / (c.g - c.b) / 6.0 + 0.166;
00264         } else if (c.b > c.g) {
00265             *max = c.b;
00266             *min = c.r;
00267             *position = (float)(c.g - c.r) / (c.b - c.r) / 6.0 + 0.498;
00268         } else {
00269             *max = c.g;
00270             *min = c.r;
00271             *position = (float)(c.b - c.r) / (c.g - c.r) / 6.0 + 0.332;
00272         }
00273     }
00274 }
00275 
00276 void ColorPixels::rainbow(uint32_t rgb)
00277 {
00278     float position;
00279     uint8_t min, max;
00280     
00281     find_wheel_options(rgb, &position, &min, &max);
00282     for (int i = 0; i < num; i++) {
00283         float current = ((int)(i + num * position) % num) / (float)num;
00284         set_color(i, wheel(current, min, max));
00285     }
00286     
00287     update();
00288 }
00289 
00290 void ColorPixels::rainbow(uint8_t r, uint8_t g, uint8_t b)
00291 {
00292     color_t c;
00293     
00294     c.r = r;
00295     c.g = g;
00296     c.b = b;
00297     
00298     rainbow(c.rgb);
00299 }
00300