ws281x.h
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1 /*
2  * Copyright 2019 Marian Buschsieweke
3  *
4  * This file is subject to the terms and conditions of the GNU Lesser
5  * General Public License v2.1. See the file LICENSE in the top level
6  * directory for more details.
7  */
8 
9 #pragma once
10 
88 #include <stdint.h>
89 
90 #include "color.h"
91 #include "periph/gpio.h"
92 #include "ws281x_backend.h"
93 #include "ws281x_constants.h"
94 #include "xtimer.h"
95 
96 #ifdef __cplusplus
97 extern "C" {
98 #endif
99 
103 #define WS281X_BYTES_PER_DEVICE (3U)
104 
108 typedef struct {
114  uint8_t *buf;
115  uint16_t numof;
116  gpio_t pin;
118 
122 typedef struct {
124 } ws281x_t;
125 
126 #if defined(WS281X_HAVE_INIT) || defined(DOXYGEN)
137 int ws281x_init(ws281x_t *dev, const ws281x_params_t *params);
138 #else
139 static inline int ws281x_init(ws281x_t *dev, const ws281x_params_t *params) {
140  dev->params = *params;
141  return 0;
142 }
143 #endif
144 
173 void ws281x_write_buffer(ws281x_t *dev, const void *buf, size_t size);
174 
175 #if defined(WS281X_HAVE_PREPARE_TRANSMISSION) || defined(DOXYGEN)
182 #else
183 static inline void ws281x_prepare_transmission(ws281x_t *dev)
184 {
185  (void)dev;
186 }
187 #endif
188 
189 #if defined(WS281X_HAVE_END_TRANSMISSION) || defined(DOXYGEN)
199 #else
200 static inline void ws281x_end_transmission(ws281x_t *dev)
201 {
202  (void)dev;
204 }
205 #endif
206 
217 void ws281x_set_buffer(void *dest, uint16_t index, color_rgb_t color);
218 
229 static inline void ws281x_set(ws281x_t *dev, uint16_t index, color_rgb_t color)
230 {
231  ws281x_set_buffer(dev->params.buf, index, color);
232 }
233 
242 static inline void ws281x_write(ws281x_t *dev)
243 {
245  ws281x_write_buffer(dev, dev->params.buf,
246  (size_t)dev->params.numof * WS281X_BYTES_PER_DEVICE);
248 }
249 
250 #ifdef __cplusplus
251 }
252 #endif
253 
Headers for the color handling module.
Low-level GPIO peripheral driver interface definitions.
static void ws281x_set(ws281x_t *dev, uint16_t index, color_rgb_t color)
Sets the color of an LED in the chain in the internal buffer.
Definition: ws281x.h:229
static void ws281x_write(ws281x_t *dev)
Writes the internal buffer to the LED chain.
Definition: ws281x.h:242
#define WS281X_BYTES_PER_DEVICE
The number of bytes to allocate in the data buffer per LED.
Definition: ws281x.h:103
void ws281x_end_transmission(ws281x_t *dev)
Ends the transmission to the WS2812/SK6812 LED chain.
int ws281x_init(ws281x_t *dev, const ws281x_params_t *params)
Initialize an WS281x RGB LED chain.
void ws281x_prepare_transmission(ws281x_t *dev)
Sets up everything needed to write data to the WS281X LED chain.
void ws281x_write_buffer(ws281x_t *dev, const void *buf, size_t size)
Writes the color data of the user supplied buffer.
void ws281x_set_buffer(void *dest, uint16_t index, color_rgb_t color)
Sets the color of an LED in the given data buffer.
static void xtimer_usleep(uint32_t microseconds)
Pause the execution of a thread for some microseconds.
Data-structure describing a RGB color.
Definition: color.h:34
Struct to hold initialization parameters for a WS281x RGB LED.
Definition: ws281x.h:108
gpio_t pin
GPIO connected to the data pin of the first LED.
Definition: ws281x.h:116
uint8_t * buf
A statically allocated data buffer storing the state of the LEDs.
Definition: ws281x.h:114
uint16_t numof
Number of chained RGB LEDs.
Definition: ws281x.h:115
Device descriptor of a WS281x RGB LED chain.
Definition: ws281x.h:122
ws281x_params_t params
Parameters of the LED chain.
Definition: ws281x.h:123
Backend configuration for WS2812/SK6812 RGB LEDs.
Constants for WS2812/SK6812 RGB LEDs.
#define WS281X_T_END_US
Time in microseconds to pull the data line low to signal end of data.
xtimer interface definitions