STM32F1-workarea : how to drive a WS2812 RGB LED using PWM and DMA

how to drive a WS2812 RGB LED using PWM and DMA

#include <stm32f10x.h>

void Delay(__IO uint32_t nCount)
{
  while(nCount--)
  {
  }
}

#define TIM3_CCR1_Address 0x40000434  // physical memory address of Timer 3 CCR1 register

#define d2r (3.14159265/180)

TIM_TimeBaseInitTypeDef TIM_TimeBaseStructure;
TIM_OCInitTypeDef TIM_OCInitStructure;
GPIO_InitTypeDef GPIO_InitStructure;
DMA_InitTypeDef DMA_InitStructure;

/* Buffer that holds one complete DMA transmission
 * Ensure that this buffer is big enough to hold
 * all data bytes that need to be sent
 *
 * The buffer size can be calculated as follows: number of LEDs * 24 bytes + 42 bytes
 *
 * This leaves us with a maximum string length of (2^16 bytes per DMA stream - 42 bytes) / 24 bytes per LED = 2728 LEDs
 */
uint16_t LED_BYTE_Buffer[ 100 ];

/* this array holds the RGB values to represent a color wheel using 256 steps on each emitter 256^3 = 16777216 colors
 */
uint8_t eightbit[ 766 ][ 3 ] =
{
{ 255, 0, 0 },
{ 254, 1, 0 },
{ 253, 2, 0 },
{ 252, 3, 0 },
{ 251, 4, 0 },
{ 250, 5, 0 },
{ 249, 6, 0 },
{ 248, 7, 0 },
{ 247, 8, 0 },
{ 246, 9, 0 },
{ 245, 10, 0 },
{ 244, 11, 0 },
{ 243, 12, 0 },
{ 242, 13, 0 },
{ 241, 14, 0 },
{ 240, 15, 0 },
{ 239, 16, 0 },
{ 238, 17, 0 },
{ 237, 18, 0 },
{ 236, 19, 0 },
{ 235, 20, 0 },
{ 234, 21, 0 },
{ 233, 22, 0 },
{ 232, 23, 0 },
{ 231, 24, 0 },
{ 230, 25, 0 },
{ 229, 26, 0 },
{ 228, 27, 0 },
{ 227, 28, 0 },
{ 226, 29, 0 },
{ 225, 30, 0 },
{ 224, 31, 0 },
{ 223, 32, 0 },
{ 222, 33, 0 },
{ 221, 34, 0 },
{ 220, 35, 0 },
{ 219, 36, 0 },
{ 218, 37, 0 },
{ 217, 38, 0 },
{ 216, 39, 0 },
{ 215, 40, 0 },
{ 214, 41, 0 },
{ 213, 42, 0 },
{ 212, 43, 0 },
{ 211, 44, 0 },
{ 210, 45, 0 },
{ 209, 46, 0 },
{ 208, 47, 0 },
{ 207, 48, 0 },
{ 206, 49, 0 },
{ 205, 50, 0 },
{ 204, 51, 0 },
{ 203, 52, 0 },
{ 202, 53, 0 },
{ 201, 54, 0 },
{ 200, 55, 0 },
{ 199, 56, 0 },
{ 198, 57, 0 },
{ 197, 58, 0 },
{ 196, 59, 0 },
{ 195, 60, 0 },
{ 194, 61, 0 },
{ 193, 62, 0 },
{ 192, 63, 0 },
{ 191, 64, 0 },
{ 190, 65, 0 },
{ 189, 66, 0 },
{ 188, 67, 0 },
{ 187, 68, 0 },
{ 186, 69, 0 },
{ 185, 70, 0 },
{ 184, 71, 0 },
{ 183, 72, 0 },
{ 182, 73, 0 },
{ 181, 74, 0 },
{ 180, 75, 0 },
{ 179, 76, 0 },
{ 178, 77, 0 },
{ 177, 78, 0 },
{ 176, 79, 0 },
{ 175, 80, 0 },
{ 174, 81, 0 },
{ 173, 82, 0 },
{ 172, 83, 0 },
{ 171, 84, 0 },
{ 170, 85, 0 },
{ 169, 86, 0 },
{ 168, 87, 0 },
{ 167, 88, 0 },
{ 166, 89, 0 },
{ 165, 90, 0 },
{ 164, 91, 0 },
{ 163, 92, 0 },
{ 162, 93, 0 },
{ 161, 94, 0 },
{ 160, 95, 0 },
{ 159, 96, 0 },
{ 158, 97, 0 },
{ 157, 98, 0 },
{ 156, 99, 0 },
{ 155, 100, 0 },
{ 154, 101, 0 },
{ 153, 102, 0 },
{ 152, 103, 0 },
{ 151, 104, 0 },
{ 150, 105, 0 },
{ 149, 106, 0 },
{ 148, 107, 0 },
{ 147, 108, 0 },
{ 146, 109, 0 },
{ 145, 110, 0 },
{ 144, 111, 0 },
{ 143, 112, 0 },
{ 142, 113, 0 },
{ 141, 114, 0 },
{ 140, 115, 0 },
{ 139, 116, 0 },
{ 138, 117, 0 },
{ 137, 118, 0 },
{ 136, 119, 0 },
{ 135, 120, 0 },
{ 134, 121, 0 },
{ 133, 122, 0 },
{ 132, 123, 0 },
{ 131, 124, 0 },
{ 130, 125, 0 },
{ 129, 126, 0 },
{ 128, 127, 0 },
{ 127, 128, 0 },
{ 126, 129, 0 },
{ 125, 130, 0 },
{ 124, 131, 0 },
{ 123, 132, 0 },
{ 122, 133, 0 },
{ 121, 134, 0 },
{ 120, 135, 0 },
{ 119, 136, 0 },
{ 118, 137, 0 },
{ 117, 138, 0 },
{ 116, 139, 0 },
{ 115, 140, 0 },
{ 114, 141, 0 },
{ 113, 142, 0 },
{ 112, 143, 0 },
{ 111, 144, 0 },
{ 110, 145, 0 },
{ 109, 146, 0 },
{ 108, 147, 0 },
{ 107, 148, 0 },
{ 106, 149, 0 },
{ 105, 150, 0 },
{ 104, 151, 0 },
{ 103, 152, 0 },
{ 102, 153, 0 },
{ 101, 154, 0 },
{ 100, 155, 0 },
{ 99, 156, 0 },
{ 98, 157, 0 },
{ 97, 158, 0 },
{ 96, 159, 0 },
{ 95, 160, 0 },
{ 94, 161, 0 },
{ 93, 162, 0 },
{ 92, 163, 0 },
{ 91, 164, 0 },
{ 90, 165, 0 },
{ 89, 166, 0 },
{ 88, 167, 0 },
{ 87, 168, 0 },
{ 86, 169, 0 },
{ 85, 170, 0 },
{ 84, 171, 0 },
{ 83, 172, 0 },
{ 82, 173, 0 },
{ 81, 174, 0 },
{ 80, 175, 0 },
{ 79, 176, 0 },
{ 78, 177, 0 },
{ 77, 178, 0 },
{ 76, 179, 0 },
{ 75, 180, 0 },
{ 74, 181, 0 },
{ 73, 182, 0 },
{ 72, 183, 0 },
{ 71, 184, 0 },
{ 70, 185, 0 },
{ 69, 186, 0 },
{ 68, 187, 0 },
{ 67, 188, 0 },
{ 66, 189, 0 },
{ 65, 190, 0 },
{ 64, 191, 0 },
{ 63, 192, 0 },
{ 62, 193, 0 },
{ 61, 194, 0 },
{ 60, 195, 0 },
{ 59, 196, 0 },
{ 58, 197, 0 },
{ 57, 198, 0 },
{ 56, 199, 0 },
{ 55, 200, 0 },
{ 54, 201, 0 },
{ 53, 202, 0 },
{ 52, 203, 0 },
{ 51, 204, 0 },
{ 50, 205, 0 },
{ 49, 206, 0 },
{ 48, 207, 0 },
{ 47, 208, 0 },
{ 46, 209, 0 },
{ 45, 210, 0 },
{ 44, 211, 0 },
{ 43, 212, 0 },
{ 42, 213, 0 },
{ 41, 214, 0 },
{ 40, 215, 0 },
{ 39, 216, 0 },
{ 38, 217, 0 },
{ 37, 218, 0 },
{ 36, 219, 0 },
{ 35, 220, 0 },
{ 34, 221, 0 },
{ 33, 222, 0 },
{ 32, 223, 0 },
{ 31, 224, 0 },
{ 30, 225, 0 },
{ 29, 226, 0 },
{ 28, 227, 0 },
{ 27, 228, 0 },
{ 26, 229, 0 },
{ 25, 230, 0 },
{ 24, 231, 0 },
{ 23, 232, 0 },
{ 22, 233, 0 },
{ 21, 234, 0 },
{ 20, 235, 0 },
{ 19, 236, 0 },
{ 18, 237, 0 },
{ 17, 238, 0 },
{ 16, 239, 0 },
{ 15, 240, 0 },
{ 14, 241, 0 },
{ 13, 242, 0 },
{ 12, 243, 0 },
{ 11, 244, 0 },
{ 10, 245, 0 },
{ 9, 246, 0 },
{ 8, 247, 0 },
{ 7, 248, 0 },
{ 6, 249, 0 },
{ 5, 250, 0 },
{ 4, 251, 0 },
{ 3, 252, 0 },
{ 2, 253, 0 },
{ 1, 254, 0 },
{ 0, 255, 0 },
{ 0, 254, 1 },
{ 0, 253, 2 },
{ 0, 252, 3 },
{ 0, 251, 4 },
{ 0, 250, 5 },
{ 0, 249, 6 },
{ 0, 248, 7 },
{ 0, 247, 8 },
{ 0, 246, 9 },
{ 0, 245, 10 },
{ 0, 244, 11 },
{ 0, 243, 12 },
{ 0, 242, 13 },
{ 0, 241, 14 },
{ 0, 240, 15 },
{ 0, 239, 16 },
{ 0, 238, 17 },
{ 0, 237, 18 },
{ 0, 236, 19 },
{ 0, 235, 20 },
{ 0, 234, 21 },
{ 0, 233, 22 },
{ 0, 232, 23 },
{ 0, 231, 24 },
{ 0, 230, 25 },
{ 0, 229, 26 },
{ 0, 228, 27 },
{ 0, 227, 28 },
{ 0, 226, 29 },
{ 0, 225, 30 },
{ 0, 224, 31 },
{ 0, 223, 32 },
{ 0, 222, 33 },
{ 0, 221, 34 },
{ 0, 220, 35 },
{ 0, 219, 36 },
{ 0, 218, 37 },
{ 0, 217, 38 },
{ 0, 216, 39 },
{ 0, 215, 40 },
{ 0, 214, 41 },
{ 0, 213, 42 },
{ 0, 212, 43 },
{ 0, 211, 44 },
{ 0, 210, 45 },
{ 0, 209, 46 },
{ 0, 208, 47 },
{ 0, 207, 48 },
{ 0, 206, 49 },
{ 0, 205, 50 },
{ 0, 204, 51 },
{ 0, 203, 52 },
{ 0, 202, 53 },
{ 0, 201, 54 },
{ 0, 200, 55 },
{ 0, 199, 56 },
{ 0, 198, 57 },
{ 0, 197, 58 },
{ 0, 196, 59 },
{ 0, 195, 60 },
{ 0, 194, 61 },
{ 0, 193, 62 },
{ 0, 192, 63 },
{ 0, 191, 64 },
{ 0, 190, 65 },
{ 0, 189, 66 },
{ 0, 188, 67 },
{ 0, 187, 68 },
{ 0, 186, 69 },
{ 0, 185, 70 },
{ 0, 184, 71 },
{ 0, 183, 72 },
{ 0, 182, 73 },
{ 0, 181, 74 },
{ 0, 180, 75 },
{ 0, 179, 76 },
{ 0, 178, 77 },
{ 0, 177, 78 },
{ 0, 176, 79 },
{ 0, 175, 80 },
{ 0, 174, 81 },
{ 0, 173, 82 },
{ 0, 172, 83 },
{ 0, 171, 84 },
{ 0, 170, 85 },
{ 0, 169, 86 },
{ 0, 168, 87 },
{ 0, 167, 88 },
{ 0, 166, 89 },
{ 0, 165, 90 },
{ 0, 164, 91 },
{ 0, 163, 92 },
{ 0, 162, 93 },
{ 0, 161, 94 },
{ 0, 160, 95 },
{ 0, 159, 96 },
{ 0, 158, 97 },
{ 0, 157, 98 },
{ 0, 156, 99 },
{ 0, 155, 100 },
{ 0, 154, 101 },
{ 0, 153, 102 },
{ 0, 152, 103 },
{ 0, 151, 104 },
{ 0, 150, 105 },
{ 0, 149, 106 },
{ 0, 148, 107 },
{ 0, 147, 108 },
{ 0, 146, 109 },
{ 0, 145, 110 },
{ 0, 144, 111 },
{ 0, 143, 112 },
{ 0, 142, 113 },
{ 0, 141, 114 },
{ 0, 140, 115 },
{ 0, 139, 116 },
{ 0, 138, 117 },
{ 0, 137, 118 },
{ 0, 136, 119 },
{ 0, 135, 120 },
{ 0, 134, 121 },
{ 0, 133, 122 },
{ 0, 132, 123 },
{ 0, 131, 124 },
{ 0, 130, 125 },
{ 0, 129, 126 },
{ 0, 128, 127 },
{ 0, 127, 128 },
{ 0, 126, 129 },
{ 0, 125, 130 },
{ 0, 124, 131 },
{ 0, 123, 132 },
{ 0, 122, 133 },
{ 0, 121, 134 },
{ 0, 120, 135 },
{ 0, 119, 136 },
{ 0, 118, 137 },
{ 0, 117, 138 },
{ 0, 116, 139 },
{ 0, 115, 140 },
{ 0, 114, 141 },
{ 0, 113, 142 },
{ 0, 112, 143 },
{ 0, 111, 144 },
{ 0, 110, 145 },
{ 0, 109, 146 },
{ 0, 108, 147 },
{ 0, 107, 148 },
{ 0, 106, 149 },
{ 0, 105, 150 },
{ 0, 104, 151 },
{ 0, 103, 152 },
{ 0, 102, 153 },
{ 0, 101, 154 },
{ 0, 100, 155 },
{ 0, 99, 156 },
{ 0, 98, 157 },
{ 0, 97, 158 },
{ 0, 96, 159 },
{ 0, 95, 160 },
{ 0, 94, 161 },
{ 0, 93, 162 },
{ 0, 92, 163 },
{ 0, 91, 164 },
{ 0, 90, 165 },
{ 0, 89, 166 },
{ 0, 88, 167 },
{ 0, 87, 168 },
{ 0, 86, 169 },
{ 0, 85, 170 },
{ 0, 84, 171 },
{ 0, 83, 172 },
{ 0, 82, 173 },
{ 0, 81, 174 },
{ 0, 80, 175 },
{ 0, 79, 176 },
{ 0, 78, 177 },
{ 0, 77, 178 },
{ 0, 76, 179 },
{ 0, 75, 180 },
{ 0, 74, 181 },
{ 0, 73, 182 },
{ 0, 72, 183 },
{ 0, 71, 184 },
{ 0, 70, 185 },
{ 0, 69, 186 },
{ 0, 68, 187 },
{ 0, 67, 188 },
{ 0, 66, 189 },
{ 0, 65, 190 },
{ 0, 64, 191 },
{ 0, 63, 192 },
{ 0, 62, 193 },
{ 0, 61, 194 },
{ 0, 60, 195 },
{ 0, 59, 196 },
{ 0, 58, 197 },
{ 0, 57, 198 },
{ 0, 56, 199 },
{ 0, 55, 200 },
{ 0, 54, 201 },
{ 0, 53, 202 },
{ 0, 52, 203 },
{ 0, 51, 204 },
{ 0, 50, 205 },
{ 0, 49, 206 },
{ 0, 48, 207 },
{ 0, 47, 208 },
{ 0, 46, 209 },
{ 0, 45, 210 },
{ 0, 44, 211 },
{ 0, 43, 212 },
{ 0, 42, 213 },
{ 0, 41, 214 },
{ 0, 40, 215 },
{ 0, 39, 216 },
{ 0, 38, 217 },
{ 0, 37, 218 },
{ 0, 36, 219 },
{ 0, 35, 220 },
{ 0, 34, 221 },
{ 0, 33, 222 },
{ 0, 32, 223 },
{ 0, 31, 224 },
{ 0, 30, 225 },
{ 0, 29, 226 },
{ 0, 28, 227 },
{ 0, 27, 228 },
{ 0, 26, 229 },
{ 0, 25, 230 },
{ 0, 24, 231 },
{ 0, 23, 232 },
{ 0, 22, 233 },
{ 0, 21, 234 },
{ 0, 20, 235 },
{ 0, 19, 236 },
{ 0, 18, 237 },
{ 0, 17, 238 },
{ 0, 16, 239 },
{ 0, 15, 240 },
{ 0, 14, 241 },
{ 0, 13, 242 },
{ 0, 12, 243 },
{ 0, 11, 244 },
{ 0, 10, 245 },
{ 0, 9, 246 },
{ 0, 8, 247 },
{ 0, 7, 248 },
{ 0, 6, 249 },
{ 0, 5, 250 },
{ 0, 4, 251 },
{ 0, 3, 252 },
{ 0, 2, 253 },
{ 0, 1, 254 },
{ 0, 0, 255 },
{ 1, 0, 254 },
{ 2, 0, 253 },
{ 3, 0, 252 },
{ 4, 0, 251 },
{ 5, 0, 250 },
{ 6, 0, 249 },
{ 7, 0, 248 },
{ 8, 0, 247 },
{ 9, 0, 246 },
{ 10, 0, 245 },
{ 11, 0, 244 },
{ 12, 0, 243 },
{ 13, 0, 242 },
{ 14, 0, 241 },
{ 15, 0, 240 },
{ 16, 0, 239 },
{ 17, 0, 238 },
{ 18, 0, 237 },
{ 19, 0, 236 },
{ 20, 0, 235 },
{ 21, 0, 234 },
{ 22, 0, 233 },
{ 23, 0, 232 },
{ 24, 0, 231 },
{ 25, 0, 230 },
{ 26, 0, 229 },
{ 27, 0, 228 },
{ 28, 0, 227 },
{ 29, 0, 226 },
{ 30, 0, 225 },
{ 31, 0, 224 },
{ 32, 0, 223 },
{ 33, 0, 222 },
{ 34, 0, 221 },
{ 35, 0, 220 },
{ 36, 0, 219 },
{ 37, 0, 218 },
{ 38, 0, 217 },
{ 39, 0, 216 },
{ 40, 0, 215 },
{ 41, 0, 214 },
{ 42, 0, 213 },
{ 43, 0, 212 },
{ 44, 0, 211 },
{ 45, 0, 210 },
{ 46, 0, 209 },
{ 47, 0, 208 },
{ 48, 0, 207 },
{ 49, 0, 206 },
{ 50, 0, 205 },
{ 51, 0, 204 },
{ 52, 0, 203 },
{ 53, 0, 202 },
{ 54, 0, 201 },
{ 55, 0, 200 },
{ 56, 0, 199 },
{ 57, 0, 198 },
{ 58, 0, 197 },
{ 59, 0, 196 },
{ 60, 0, 195 },
{ 61, 0, 194 },
{ 62, 0, 193 },
{ 63, 0, 192 },
{ 64, 0, 191 },
{ 65, 0, 190 },
{ 66, 0, 189 },
{ 67, 0, 188 },
{ 68, 0, 187 },
{ 69, 0, 186 },
{ 70, 0, 185 },
{ 71, 0, 184 },
{ 72, 0, 183 },
{ 73, 0, 182 },
{ 74, 0, 181 },
{ 75, 0, 180 },
{ 76, 0, 179 },
{ 77, 0, 178 },
{ 78, 0, 177 },
{ 79, 0, 176 },
{ 80, 0, 175 },
{ 81, 0, 174 },
{ 82, 0, 173 },
{ 83, 0, 172 },
{ 84, 0, 171 },
{ 85, 0, 170 },
{ 86, 0, 169 },
{ 87, 0, 168 },
{ 88, 0, 167 },
{ 89, 0, 166 },
{ 90, 0, 165 },
{ 91, 0, 164 },
{ 92, 0, 163 },
{ 93, 0, 162 },
{ 94, 0, 161 },
{ 95, 0, 160 },
{ 96, 0, 159 },
{ 97, 0, 158 },
{ 98, 0, 157 },
{ 99, 0, 156 },
{ 100, 0, 155 },
{ 101, 0, 154 },
{ 102, 0, 153 },
{ 103, 0, 152 },
{ 104, 0, 151 },
{ 105, 0, 150 },
{ 106, 0, 149 },
{ 107, 0, 148 },
{ 108, 0, 147 },
{ 109, 0, 146 },
{ 110, 0, 145 },
{ 111, 0, 144 },
{ 112, 0, 143 },
{ 113, 0, 142 },
{ 114, 0, 141 },
{ 115, 0, 140 },
{ 116, 0, 139 },
{ 117, 0, 138 },
{ 118, 0, 137 },
{ 119, 0, 136 },
{ 120, 0, 135 },
{ 121, 0, 134 },
{ 122, 0, 133 },
{ 123, 0, 132 },
{ 124, 0, 131 },
{ 125, 0, 130 },
{ 126, 0, 129 },
{ 127, 0, 128 },
{ 128, 0, 127 },
{ 129, 0, 126 },
{ 130, 0, 125 },
{ 131, 0, 124 },
{ 132, 0, 123 },
{ 133, 0, 122 },
{ 134, 0, 121 },
{ 135, 0, 120 },
{ 136, 0, 119 },
{ 137, 0, 118 },
{ 138, 0, 117 },
{ 139, 0, 116 },
{ 140, 0, 115 },
{ 141, 0, 114 },
{ 142, 0, 113 },
{ 143, 0, 112 },
{ 144, 0, 111 },
{ 145, 0, 110 },
{ 146, 0, 109 },
{ 147, 0, 108 },
{ 148, 0, 107 },
{ 149, 0, 106 },
{ 150, 0, 105 },
{ 151, 0, 104 },
{ 152, 0, 103 },
{ 153, 0, 102 },
{ 154, 0, 101 },
{ 155, 0, 100 },
{ 156, 0, 99 },
{ 157, 0, 98 },
{ 158, 0, 97 },
{ 159, 0, 96 },
{ 160, 0, 95 },
{ 161, 0, 94 },
{ 162, 0, 93 },
{ 163, 0, 92 },
{ 164, 0, 91 },
{ 165, 0, 90 },
{ 166, 0, 89 },
{ 167, 0, 88 },
{ 168, 0, 87 },
{ 169, 0, 86 },
{ 170, 0, 85 },
{ 171, 0, 84 },
{ 172, 0, 83 },
{ 173, 0, 82 },
{ 174, 0, 81 },
{ 175, 0, 80 },
{ 176, 0, 79 },
{ 177, 0, 78 },
{ 178, 0, 77 },
{ 179, 0, 76 },
{ 180, 0, 75 },
{ 181, 0, 74 },
{ 182, 0, 73 },
{ 183, 0, 72 },
{ 184, 0, 71 },
{ 185, 0, 70 },
{ 186, 0, 69 },
{ 187, 0, 68 },
{ 188, 0, 67 },
{ 189, 0, 66 },
{ 190, 0, 65 },
{ 191, 0, 64 },
{ 192, 0, 63 },
{ 193, 0, 62 },
{ 194, 0, 61 },
{ 195, 0, 60 },
{ 196, 0, 59 },
{ 197, 0, 58 },
{ 198, 0, 57 },
{ 199, 0, 56 },
{ 200, 0, 55 },
{ 201, 0, 54 },
{ 202, 0, 53 },
{ 203, 0, 52 },
{ 204, 0, 51 },
{ 205, 0, 50 },
{ 206, 0, 49 },
{ 207, 0, 48 },
{ 208, 0, 47 },
{ 209, 0, 46 },
{ 210, 0, 45 },
{ 211, 0, 44 },
{ 212, 0, 43 },
{ 213, 0, 42 },
{ 214, 0, 41 },
{ 215, 0, 40 },
{ 216, 0, 39 },
{ 217, 0, 38 },
{ 218, 0, 37 },
{ 219, 0, 36 },
{ 220, 0, 35 },
{ 221, 0, 34 },
{ 222, 0, 33 },
{ 223, 0, 32 },
{ 224, 0, 31 },
{ 225, 0, 30 },
{ 226, 0, 29 },
{ 227, 0, 28 },
{ 228, 0, 27 },
{ 229, 0, 26 },
{ 230, 0, 25 },
{ 231, 0, 24 },
{ 232, 0, 23 },
{ 233, 0, 22 },
{ 234, 0, 21 },
{ 235, 0, 20 },
{ 236, 0, 19 },
{ 237, 0, 18 },
{ 238, 0, 17 },
{ 239, 0, 16 },
{ 240, 0, 15 },
{ 241, 0, 14 },
{ 242, 0, 13 },
{ 243, 0, 12 },
{ 244, 0, 11 },
{ 245, 0, 10 },
{ 246, 0, 9 },
{ 247, 0, 8 },
{ 248, 0, 7 },
{ 249, 0, 6 },
{ 250, 0, 5 },
{ 251, 0, 4 },
{ 252, 0, 3 },
{ 253, 0, 2 },
{ 254, 0, 1 },
{ 255, 0, 0 }, };

void Timer3_init( void )
{
  uint16_t PrescalerValue;

  RCC_APB2PeriphClockCmd( RCC_APB2Periph_GPIOA, ENABLE );
  /* GPIOA Configuration: TIM3 Channel 1 as alternate function push-pull */
  GPIO_InitStructure.GPIO_Pin = GPIO_Pin_6;
  GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AF_PP;
  GPIO_InitStructure.GPIO_Speed = GPIO_Speed_50MHz;
  GPIO_Init( GPIOA, &GPIO_InitStructure );

  RCC_APB1PeriphClockCmd( RCC_APB1Periph_TIM3, ENABLE );
  /* Compute the prescaler value */
  PrescalerValue = (uint16_t) ( SystemCoreClock / 24000000 ) - 1;
  /* Time base configuration */
  TIM_TimeBaseStructure.TIM_Period = 29; // 800kHz
  TIM_TimeBaseStructure.TIM_Prescaler = PrescalerValue;
  TIM_TimeBaseStructure.TIM_ClockDivision = 0;
  TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
  TIM_TimeBaseInit( TIM3, &TIM_TimeBaseStructure );

  /* PWM1 Mode configuration: Channel1 */
  TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM1;
  TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
  TIM_OCInitStructure.TIM_Pulse = 0;
  TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_High;
  TIM_OC1Init( TIM3, &TIM_OCInitStructure );

  /* configure DMA */
  /* DMA clock enable */
  RCC_AHBPeriphClockCmd( RCC_AHBPeriph_DMA1, ENABLE );

  /* DMA1 Channel6 Config */
  DMA_DeInit( DMA1_Channel6 );

  DMA_InitStructure.DMA_PeripheralBaseAddr = (uint32_t) TIM3_CCR1_Address; // physical address of Timer 3 CCR1
  DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t) LED_BYTE_Buffer; // this is the buffer memory
  DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralDST; // data shifted from memory to peripheral
  DMA_InitStructure.DMA_BufferSize = 42;
  DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
  DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable; // automatically increase buffer index
  DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_HalfWord;
  DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_HalfWord;
  DMA_InitStructure.DMA_Mode = DMA_Mode_Normal; // stop DMA feed after buffer size is reached
  DMA_InitStructure.DMA_Priority = DMA_Priority_High;
  DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;

  DMA_Init( DMA1_Channel6, &DMA_InitStructure );

  /* TIM3 CC1 DMA Request enable */
  TIM_DMACmd( TIM3, TIM_DMA_CC1, ENABLE );
}

/* This function sends data bytes out to a string of WS2812s
 * The first argument is a pointer to the first RGB triplet to be sent -- color
 * The seconds argument is the number of LEDs in the chain -- len
 *
 * This will result in the RGB triplet passed by argument 1 being sent to
 * the LED that is the furthest away from the controller (the point where
 * data is injected into the chain)
 */
void WS2812_send( uint8_t (*color)[ 3 ], uint16_t len )
{
  uint8_t i, j;
  uint8_t led;
  uint16_t memaddr;
  uint16_t buffersize;

  buffersize = ( len * 24 ) + 42; // number of bytes needed is #LEDs * 24 bytes + 42 trailing bytes
  memaddr = 0;        // reset buffer memory index
  led = 0;          // reset led index

  // fill transmit buffer with correct compare values to achieve
  // correct pulse widths according to color values
  while ( len )
  {
    for ( j = 0; j < 8; j++ )         // GREEN data
    {
      if ( ( color[ led ][ 1 ] << j ) & 0x80 ) // data sent MSB first, j = 0 is MSB j = 7 is LSB
      {
        LED_BYTE_Buffer[ memaddr ] = 17;  // compare value for logical 1
      }
      else
      {
        LED_BYTE_Buffer[ memaddr ] = 9; // compare value for logical 0
      }
      memaddr++;
    }

    for ( j = 0; j < 8; j++ )         // RED data
    {
      if ( ( color[ led ][ 0 ] << j ) & 0x80 ) // data sent MSB first, j = 0 is MSB j = 7 is LSB
      {
        LED_BYTE_Buffer[ memaddr ] = 17;  // compare value for logical 1
      }
      else
      {
        LED_BYTE_Buffer[ memaddr ] = 9; // compare value for logical 0
      }
      memaddr++;
    }

    for ( j = 0; j < 8; j++ )         // BLUE data
    {
      if ( ( color[ led ][ 2 ] << j ) & 0x80 ) // data sent MSB first, j = 0 is MSB j = 7 is LSB
      {
        LED_BYTE_Buffer[ memaddr ] = 17;  // compare value for logical 1
      }
      else
      {
        LED_BYTE_Buffer[ memaddr ] = 9; // compare value for logical 0
      }
      memaddr++;
    }

    led++;
    len--;
  }

  // add needed delay at end of byte cycle, pulsewidth = 0
  while ( memaddr < buffersize )
  {
    LED_BYTE_Buffer[ memaddr ] = 0;
    memaddr++;
  }

  DMA_SetCurrDataCounter( DMA1_Channel6, buffersize ); // load number of bytes to be transferred
  DMA_Cmd( DMA1_Channel6, ENABLE );       // enable DMA channel 6
  TIM_Cmd( TIM3, ENABLE );            // enable Timer 3
  while ( !DMA_GetFlagStatus( DMA1_FLAG_TC6 ) )
    ;   // wait until transfer complete
  TIM_Cmd( TIM3, DISABLE );           // disable Timer 3
  DMA_Cmd( DMA1_Channel6, DISABLE );      // disable DMA channel 6
  DMA_ClearFlag( DMA1_FLAG_TC6 ); // clear DMA1 Channel 6 transfer complete flag
}

int main( void )
{
  Timer3_init( );

  int16_t i;

  while ( 1 )
  {
    /* first cycle through the colors on 2 LEDs chained together
     * last LED in the chain will receive first sent triplet
     * --> last LED in the chain will ‘lead‘
     */
    for ( i = 0; i < 766; i += 2 )
    {
      WS2812_send( &eightbit[ i ], 2 );
      Delay( 50000L );
    }

    /* cycle through the colors on only one LED
     * this time only the first LED that data is
     * fed into will update
     */
    for ( i = 0; i < 766; i += 1 )
    {
      WS2812_send( &eightbit[ i ], 1 );
      Delay( 50000L );
    }
  }
}
时间： 2024-08-02 16:45:13

STM32F1-workarea : how to drive a WS2812 RGB LED using PWM and DMA的相关文章

用树莓派实现RGB LED的颜色控制——C语言版本号

用树莓派实现RGB LED的颜色控制  RGB色彩模式是工业界的一种颜色标准.是通过对红(R).绿(G).蓝(B)三个颜色通道的变化以及它们相互之间的叠加来得到各式各样的颜色的,RGB即是代 表红.绿.蓝三个通道的颜色.这个标准差点儿包含了人类视力所能感知的全部颜色,是眼下运用最广的颜色系统之中的一个.RGB色彩模式使用RGB模型为图像中每个像素的RGB分量分配一个0~255范围内的强度值. RGB图像仅仅使用三种颜色.就能够使它们依照不同的比例混合,从而得到各种各样的颜色. 在实际的控制中.往

用树莓派实现RGB LED的颜色控制

用树莓派实现RGB LED的颜色控制  RGB色彩模式是工业界的一种颜色标准,是通过对红(R).绿(G).蓝(B)三个颜色通道的变化以及它们相互之间的叠加来得到各式各样的颜色的,RGB即是代 表红.绿.蓝三个通道的颜色,这个标准几乎包括了人类视力所能感知的所有颜色,是目前运用最广的颜色系统之一.RGB色彩模式使用RGB模型为图像中每一个像素的RGB分量分配一个0~255范围内的强度值.RGB图像只使用三种颜色,就可以使它们按照不同的比例混合,从而得到各种各样的颜色. 在实际的控制中,往往通过PW

用树莓派实现RGB LED的颜色控制——Python版本

电路连接方式请参考另一篇博文:[用树莓派实现RGB LED的颜色控制--C语言版本] Python代码: #!/usr/bin/env python #********************************************************* # File Name :rgb.py # Author :Jason Dai # Date : 2015/02/04 #*******************************************************

共阳极RGB LED二极管

1)RGB LED二极管有四个引脚,它把3个普通led被封装在其内部,这三个led颜色分别为红.绿.蓝三种颜色,通过控制各个LED的亮度,你可以混合出几乎任何你想要的颜色,如下图: 2)RGB LED也分共阴极和共阳极. 共阴极:把所有负极端全部接一块接负极,即公共端为负极. 共阳极:把所有正极端全部接一块接正极,即公共端为正极. 3)共阳极RGB LED  : R.G.B这三个脚分别引出接负极,这三脚之外的第四脚为公共端接正极(阳极).如下图: 由图可看出共阳RGB LED共有4个引脚,常见的

Arduino 操作共阴极RGB LED

一.原理图 二. 实物图 三.完整事例代码,三种颜色不停的交替闪烁 实验结果自己运行观察

使用 Cortana 语音助手和 Arduino 声音控制 RGB Led 灯！

https://www.wandianshenme.com/play/use-cortana-arduino-control-rgb-led-strip/ 原文地址:https://www.cnblogs.com/kekeoutlook/p/8536764.html

小伙伴们来看啊！开源智能机 Librem 5 规格发布。

下图是 Librem 5 的高配版规格: (看到这配置,忍不住吐槽一句:放到三年前都看不上……) Librem 5 的更详细规格如下: CPU: i.MX8M @ max. 1.5GHz 四核 Cortex A53,64 位 ARM GPU:OpenGL/ES 3.1, Vulkan, OpenCL 1.2 Auxiliary Cortex M4 运行内存:3GB RAM 存储: 内置 32GB eMMC 支持 microSD 存储扩展槽 (max 2 TB) 显示:5.7″ IPS TFT s

0xWS2812 STM32 driver for WS2812(B) RGB LEDs

0xWS2812 STM32 driver for WS2812(B) RGB LEDs 0xWS2812 pronounced "hex-WS2812" This code aims at providing a basic interface to the WS2812(B) individually addressable RGB LEDs by WorldSemi. The code outputs 16 parallel data streams to 16 parallel

【雕爷学编程】Arduino动手做（60）---WS2812直条8位模块

37款传感器与执行器的提法,在网络上广泛流传,其实Arduino能够兼容的传感器模块肯定是不止这37种的.鉴于本人手头积累了一些传感器和执行器模块,依照实践出真知(一定要动手做)的理念,以学习和交流为目的,这里准备逐一动手尝试系列实验,不管成功(程序走通)与否,都会记录下来---小小的进步或是搞不掂的问题,希望能够抛砖引玉. [Arduino]168种传感器模块系列实验(资料+代码+图形+仿真) 实验六十: 直条8位 WS2812B 5050 RGB LED内置全彩驱动彩灯模块 WS2812B芯