6 #define BYTES_FOR_LED_BYTE 4
8 #define BYTES_FOR_LED BYTES_FOR_LED_BYTE*NB_COLORS
9 #define DATA_SIZE BYTES_FOR_LED*NB_LEDS
10 #define RESET_SIZE 200
12 // Define the spi your LEDs are plugged to here
13 #define LEDS_SPI WS2812_SPI
14 // Define the number of LEDs you wish to control in your LED strip
15 #define NB_LEDS RGBLED_NUM
19 static uint8_t txbuf[DATA_SIZE + RESET_SIZE];
20 static uint8_t get_protocol_eq(uint8_t data, int pos);
23 * This lib is meant to be used asynchronously, thus the colors contained in
24 * the txbuf will be sent in loop, so that the colors are always the ones you
25 * put in the table (the user thus have less to worry about)
27 * Since the data are sent via DMA, and the call to spiSend is a blocking one,
28 * the processor ressources are not used to much, if you see your program being
29 * too slow, simply add a:
30 * chThdSleepMilliseconds(x);
31 * after the spiSend, where you increment x untill you are satisfied with your
32 * program speed, another trick may be to lower this thread priority : your call
34 static THD_WORKING_AREA(LEDS_THREAD_WA, 128);
35 static THD_FUNCTION(ledsThread, arg) {
38 spiSend(&LEDS_SPI, DATA_SIZE + RESET_SIZE, txbuf);
44 * 'Led spiral' is a simple demo in which we put all the leds to the same
45 * color, where this color does all the hsv circle in loop.
46 * If you want to launch the thread that will chage the led colors to the
47 * appropriate value, simply set LED_SPIRAL to 1.
50 static THD_WORKING_AREA(HSVTRANS_WA, 128);
51 static THD_FUNCTION(hsv_transThread, arg) {
53 hsv_color color = {0, 255, 255};
57 set_leds_color_hsv(color);
58 chThdSleepMilliseconds(50);
63 static const SPIConfig spicfg = {
67 SPI_CR1_BR_1|SPI_CR1_BR_0 // baudrate : fpclk / 8 => 1tick is 0.32us
71 * Function used to initialize the driver.
73 * Starts by shutting off all the LEDs.
74 * Then gets access on the LED_SPI driver.
75 * May eventually launch an animation on the LEDs (e.g. a thread setting the
79 for(int i = 0; i < RESET_SIZE; i++)
80 txbuf[DATA_SIZE+i] = 0x00;
81 spiAcquireBus(&LEDS_SPI); /* Acquire ownership of the bus. */
82 spiStart(&LEDS_SPI, &spicfg); /* Setup transfer parameters. */
83 spiSelect(&LEDS_SPI); /* Slave Select assertion. */
84 chThdCreateStatic(LEDS_THREAD_WA, sizeof(LEDS_THREAD_WA),NORMALPRIO, ledsThread, NULL);
86 chThdCreateStatic(HSVTRANS_WA, sizeof(HSVTRANS_WA),
87 NORMALPRIO, hsv_transThread, NULL);
92 * As the trick here is to use the SPI to send a huge pattern of 0 and 1 to
93 * the ws2812b protocol, we use this helper function to translate bytes into
94 * 0s and 1s for the LED (with the appropriate timing).
96 static uint8_t get_protocol_eq(uint8_t data, int pos){
98 if (data & (1 << (2*(3-pos))))
102 if (data & (2 << (2*(3-pos))))
111 // * If you want to set a LED's color in the RGB color space, simply call this
112 // * function with a hsv_color containing the desired color and the index of the
113 // * led on the LED strip (starting from 0, the first one being the closest the
114 // * first plugged to the board)
116 // * Only set the color of the LEDs through the functions given by this API
117 // * (unless you really know what you are doing)
119 void set_led_color_rgb(LED_TYPE color, int pos){
120 for(int j = 0; j < 4; j++)
121 txbuf[BYTES_FOR_LED*pos + j] = get_protocol_eq(color.g, j);
122 for(int j = 0; j < 4; j++)
123 txbuf[BYTES_FOR_LED*pos + BYTES_FOR_LED_BYTE+j] = get_protocol_eq(color.r, j);
124 for(int j = 0; j < 4; j++)
125 txbuf[BYTES_FOR_LED*pos + BYTES_FOR_LED_BYTE*2+j] = get_protocol_eq(color.b, j);
129 void WS2812_init(void) {
133 void ws2812_setleds(LED_TYPE *ledarray, uint16_t number_of_leds) {
135 while (i < number_of_leds) {
136 set_led_color_rgb(ledarray[i], i);
142 void set_leds_color_rgb(LED_TYPE color){
143 for(int i = 0; i < NB_LEDS; i++)
144 set_led_color_rgb(color, i);
148 void ws2812_setleds_rgbw(LED_TYPE *ledarray, uint16_t number_of_leds) {