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qmk_firmware

custom branch of QMK firmware git clone https://anongit.hacktivis.me/git/qmk_firmware.git

ws2812_bitbang.c (4344B)

    

  1. #include "ws2812.h"
  3. #include "gpio.h"
  4. #include "chibios_config.h"
  6. // DEPRECATED - DO NOT USE
  7. #if defined(NOP_FUDGE)
  8. #    define WS2812_BITBANG_NOP_FUDGE NOP_FUDGE
  9. #endif
  11. /* Adapted from https://github.com/bigjosh/SimpleNeoPixelDemo/ */
  13. #ifndef WS2812_BITBANG_NOP_FUDGE
  14. #    if defined(STM32F0XX) || defined(STM32F1XX) || defined(GD32VF103) || defined(STM32F3XX) || defined(STM32F4XX) || defined(STM32L0XX) || defined(WB32F3G71xx) || defined(WB32FQ95xx) || defined(AT32F415)
  15. #        define WS2812_BITBANG_NOP_FUDGE 0.4
  16. #    else
  17. #        if defined(RP2040)
  18. #            error "Please use `vendor` WS2812 driver for RP2040"
  19. #        else
  20. #            error "WS2812_BITBANG_NOP_FUDGE configuration required"
  21. #        endif
  22. #        define WS2812_BITBANG_NOP_FUDGE 1 // this just pleases the compile so the above error is easier to spot
  23. #    endif
  24. #endif
  26. // Push Pull or Open Drain Configuration
  27. // Default Push Pull
  28. #ifndef WS2812_EXTERNAL_PULLUP
  29. #    define WS2812_OUTPUT_MODE PAL_MODE_OUTPUT_PUSHPULL
  30. #else
  31. #    define WS2812_OUTPUT_MODE PAL_MODE_OUTPUT_OPENDRAIN
  32. #endif
  34. // The reset gap can be 6000 ns, but depending on the LED strip it may have to be increased
  35. // to values like 600000 ns. If it is too small, the pixels will show nothing most of the time.
  36. #ifndef WS2812_RES
  37. #    define WS2812_RES (1000 * WS2812_TRST_US) // Width of the low gap between bits to cause a frame to latch
  38. #endif
  40. #define NUMBER_NOPS 6
  41. #define CYCLES_PER_SEC (CPU_CLOCK / NUMBER_NOPS * WS2812_BITBANG_NOP_FUDGE)
  42. #define NS_PER_SEC (1000000000L) // Note that this has to be SIGNED since we want to be able to check for negative values of derivatives
  43. #define NS_PER_CYCLE (NS_PER_SEC / CYCLES_PER_SEC)
  44. #define NS_TO_CYCLES(n) ((n) / NS_PER_CYCLE)
  46. #define wait_ns(x)                                  \
  47.     do {                                            \
  48.         for (int i = 0; i < NS_TO_CYCLES(x); i++) { \
  49.             __asm__ volatile("nop\n\t"              \
  50.                              "nop\n\t"              \
  51.                              "nop\n\t"              \
  52.                              "nop\n\t"              \
  53.                              "nop\n\t"              \
  54.                              "nop\n\t");            \
  55.         }                                           \
  56.     } while (0)
  58. void sendByte(uint8_t byte) {
  59.     // WS2812 protocol wants most significant bits first
  60.     for (unsigned char bit = 0; bit < 8; bit++) {
  61.         bool is_one = byte & (1 << (7 - bit));
  62.         // using something like wait_ns(is_one ? T1L : T0L) here throws off timings
  63.         if (is_one) {
  64.             // 1
  65.             gpio_write_pin_high(WS2812_DI_PIN);
  66.             wait_ns(WS2812_T1H);
  67.             gpio_write_pin_low(WS2812_DI_PIN);
  68.             wait_ns(WS2812_T1L);
  69.         } else {
  70.             // 0
  71.             gpio_write_pin_high(WS2812_DI_PIN);
  72.             wait_ns(WS2812_T0H);
  73.             gpio_write_pin_low(WS2812_DI_PIN);
  74.             wait_ns(WS2812_T0L);
  75.         }
  76.     }
  77. }
  79. ws2812_led_t ws2812_leds[WS2812_LED_COUNT];
  81. void ws2812_init(void) {
  82.     palSetLineMode(WS2812_DI_PIN, WS2812_OUTPUT_MODE);
  83. }
  85. void ws2812_set_color(int index, uint8_t red, uint8_t green, uint8_t blue) {
  86.     ws2812_leds[index].r = red;
  87.     ws2812_leds[index].g = green;
  88.     ws2812_leds[index].b = blue;
  89. #if defined(WS2812_RGBW)
  90.     ws2812_rgb_to_rgbw(&ws2812_leds[index]);
  91. #endif
  92. }
  94. void ws2812_set_color_all(uint8_t red, uint8_t green, uint8_t blue) {
  95.     for (int i = 0; i < WS2812_LED_COUNT; i++) {
  96.         ws2812_set_color(i, red, green, blue);
  97.     }
  98. }
  100. void ws2812_flush(void) {
  101.     // this code is very time dependent, so we need to disable interrupts
  102.     chSysLock();
  104.     for (int i = 0; i < WS2812_LED_COUNT; i++) {
  105.         // WS2812 protocol dictates grb order
  106. #if (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_GRB)
  107.         sendByte(ws2812_leds[i].g);
  108.         sendByte(ws2812_leds[i].r);
  109.         sendByte(ws2812_leds[i].b);
  110. #elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_RGB)
  111.         sendByte(ws2812_leds[i].r);
  112.         sendByte(ws2812_leds[i].g);
  113.         sendByte(ws2812_leds[i].b);
  114. #elif (WS2812_BYTE_ORDER == WS2812_BYTE_ORDER_BGR)
  115.         sendByte(ws2812_leds[i].b);
  116.         sendByte(ws2812_leds[i].g);
  117.         sendByte(ws2812_leds[i].r);
  118. #endif
  120. #ifdef WS2812_RGBW
  121.         sendByte(ws2812_leds[i].w);
  122. #endif
  123.     }
  125.     wait_ns(WS2812_RES);
  127.     chSysUnlock();
  128. }