Formula UBC: Laser Timing Gates Receiver

static volatile int64_t clock_offset_us = 0;
static volatile int64_t last_beam_break_us = 0;
static volatile bool beam_break_event = false;

int64_t master_time_now_us(void)
{
    return esp_timer_get_time() + clock_offset_us;
}

void on_sync_packet(const SyncPacket *pkt)
{
    int64_t t_client_rx_us = esp_timer_get_time();
    int64_t one_way_us = pkt->round_trip_us / 2;

    clock_offset_us =
        (pkt->master_tx_us + one_way_us) - t_client_rx_us;
}

void IRAM_ATTR beam_break_isr(void)
{
    last_beam_break_us = master_time_now_us();
    beam_break_event = true;
}

void process_lap_event(void)
{
    if (!beam_break_event) return;
    beam_break_event = false;

    send_timestamp_to_master(last_beam_break_us);
}