ws2812.h

 1/*
 2 * This program is free software: you can redistribute it and/or modify
 3 * it under the terms of the GNU General Public License as published by
 4 * the Free Software Foundation, either version 2 of the License, or
 5 * (at your option) any later version.
 6 *
 7 * This program is distributed in the hope that it will be useful,
 8 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 9 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
10 * GNU General Public License for more details.
11 *
12 * You should have received a copy of the GNU General Public License
13 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
14 */
15
16#pragma once
17
18#include "util.h"
19
20/*
21 * The WS2812 datasheets define T1H 900ns, T0H 350ns, T1L 350ns, T0L 900ns. Hence, by default, these
22 * are chosen to be conservative and avoid problems rather than for maximum throughput; in the code,
23 * this is done by default using a WS2812_TIMING parameter that accounts for the whole window (1250ns)
24 * and defining T1H and T0H; T1L and T0L are obtained by subtracting their low counterparts from the window.
25 *
26 * However, there are certain "WS2812"-like LEDs, like the SK6812s, which work in a similar
27 * communication topology but use different timings for the window and the T1L, T1H, T0L and T0H.
28 * This means that, albeit the same driver being applicable, the timings must be adapted.
29 */
30
31#ifndef WS2812_TIMING
32#    define WS2812_TIMING 1250
33#endif
34
35#ifndef WS2812_T1H
36#    define WS2812_T1H 900 // Width of a 1 bit in ns
37#endif
38
39#ifndef WS2812_T1L
40#    define WS2812_T1L (WS2812_TIMING - WS2812_T1H) // Width of a 1 bit in ns
41#endif
42
43#ifndef WS2812_T0H
44#    define WS2812_T0H 350 // Width of a 0 bit in ns
45#endif
46
47#ifndef WS2812_T0L
48#    define WS2812_T0L (WS2812_TIMING - WS2812_T0H) // Width of a 0 bit in ns
49#endif
50
51/*
52 * Older WS2812s can handle a reset time (TRST) of 50us, but recent
53 * component revisions require a minimum of 280us.
54 */
55#if !defined(WS2812_TRST_US)
56#    define WS2812_TRST_US 280
57#endif
58
59#if defined(RGBLIGHT_WS2812)
60#    define WS2812_LED_COUNT RGBLIGHT_LED_COUNT
61#elif defined(RGB_MATRIX_WS2812)
62#    define WS2812_LED_COUNT RGB_MATRIX_LED_COUNT
63#endif
64
65#define WS2812_BYTE_ORDER_RGB 0
66#define WS2812_BYTE_ORDER_GRB 1
67#define WS2812_BYTE_ORDER_BGR 2
68
69#ifndef WS2812_BYTE_ORDER
70#    define WS2812_BYTE_ORDER WS2812_BYTE_ORDER_GRB
71#endif
72
73typedef struct PACKED ws2812_led_t {
74#if (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_GRB)
75    uint8_t g;
76    uint8_t r;
77    uint8_t b;
78#elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_RGB)
79    uint8_t r;
80    uint8_t g;
81    uint8_t b;
82#elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_BGR)
83    uint8_t b;
84    uint8_t g;
85    uint8_t r;
86#endif
87#ifdef WS2812_RGBW
88    uint8_t w;
89#endif
90} ws2812_led_t;
91
92void ws2812_init(void);
93void ws2812_set_color(int index, uint8_t red, uint8_t green, uint8_t blue);
94void ws2812_set_color_all(uint8_t red, uint8_t green, uint8_t blue);
95void ws2812_flush(void);
96
97void ws2812_rgb_to_rgbw(ws2812_led_t *led);