.pio_version 1

.define public CLK_PIN 21

.program fpga

wait 1 gpio CLK_PIN
wait 0 gpio CLK_PIN
in pins, 8

% c-sdk {

static inline void fpga_program_init(PIO pio, uint sm, uint offset, uint pin)
{
  pio_sm_config c = fpga_program_get_default_config(offset);

  sm_config_set_in_pins(&c, pin);
  pio_sm_set_consecutive_pindirs(pio, sm, pin, 8, false);
  for (int i = 0; i < 8; i++)
  {
    pio_gpio_init(pio, pin + i);
  }

  sm_config_set_in_shift(
    &c,
    false,
    true,
    8
  );

  sm_config_set_fifo_join(&c, PIO_FIFO_JOIN_RX);

  pio_sm_init(pio, sm, offset, &c);
  pio_sm_set_enabled(pio, sm, true);
}

%}