rp2040_pio.h

// -------------------------------------------------- //
// This file is autogenerated by pioasm; do not edit! //
// -------------------------------------------------- //

// Unless you know what you are doing...
// Lines 47 and 52 have been edited to set transmit bit count

#if !PICO_NO_HARDWARE
#include "hardware/pio.h"
#endif

// ------ //
// ws2812 //
// ------ //

#define ws2812_wrap_target 0
#define ws2812_wrap 3

#define ws2812_T1 2
#define ws2812_T2 5
#define ws2812_T3 3

static const uint16_t ws2812_program_instructions[] = {
    //     .wrap_target
    0x6221, //  0: out    x, 1            side 0 [2]
    0x1123, //  1: jmp    !x, 3           side 1 [1]
    0x1400, //  2: jmp    0               side 1 [4]
    0xa442, //  3: nop                    side 0 [4]
            //     .wrap
};

#if !PICO_NO_HARDWARE
static const struct pio_program ws2812_program = {
    .instructions = ws2812_program_instructions,
    .length = 4,
    .origin = -1,
};

static inline pio_sm_config ws2812_program_get_default_config(uint offset) {
  pio_sm_config c = pio_get_default_sm_config();
  sm_config_set_wrap(&c, offset + ws2812_wrap_target, offset + ws2812_wrap);
  sm_config_set_sideset(&c, 1, false, false);
  return c;
}

#include "hardware/clocks.h"
static inline void ws2812_program_init(PIO pio, uint sm, uint offset, uint pin,
                                       float freq, uint bits) {
  pio_gpio_init(pio, pin);
  pio_sm_set_consecutive_pindirs(pio, sm, pin, 1, true);
  pio_sm_config c = ws2812_program_get_default_config(offset);
  sm_config_set_sideset_pins(&c, pin);
  sm_config_set_out_shift(&c, false, true,
                          bits); // <----<<< Length changed to "bits"
  sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_TX);
  int cycles_per_bit = ws2812_T1 + ws2812_T2 + ws2812_T3;
  float div = clock_get_hz(clk_sys) / (freq * cycles_per_bit);
  sm_config_set_clkdiv(&c, div);
  pio_sm_init(pio, sm, offset, &c);
  pio_sm_set_enabled(pio, sm, true);
}

#endif