Constant ws2818_rgb_led_spi_driver::timings::encoding::WS2812_LOGICAL_ZERO_BYTES

pub const WS2812_LOGICAL_ZERO_BYTES: [u8; 2];

See code comments above where this value comes from! These are the bits to send via SPI MOSI that represent a logical 0 on WS2812 RGB LED interface. Frequency + length results in the proper timings.