Method init

libraries/AP_HAL_Linux/RCInput_RPI.cpp:524–572

}

void RCInput_RPI::init()
{
    uint64_t signal_states(0);

#if CONFIG_HAL_BOARD_SUBTYPE == HAL_BOARD_SUBTYPE_LINUX_ERLEBRAIN2
    _version = LINUX_BOARD_TYPE::RPI_2_3_ZERO2;
#else
    _version = UtilRPI::from(hal.util)->detect_linux_board_type();
#endif

    set_physical_addresses();
    // Init memory for buffer and for DMA control blocks.
    // See comments in "init_ctrl_data()" to understand values "2" and "15"
    circle_buffer = NEW_NOTHROW Memory_table(RCIN_RPI_BUFFER_LENGTH * 2, _version);
    con_blocks = NEW_NOTHROW Memory_table(RCIN_RPI_BUFFER_LENGTH * 15, _version);

    init_registers();

    // Enable PPM or PWM input
    for (uint32_t i = 0; i < RCIN_RPI_CHN_NUM; ++i) {
        rc_channels[i].enable_pin = hal.gpio->channel(RcChnGpioTbl[i]);
        rc_channels[i].enable_pin->mode(HAL_GPIO_INPUT);
    }

    // Configuration
    set_sigaction();
    init_ctrl_data();
    init_PCM();
    init_DMA();

    // Wait a bit to let DMA fill queues and come to stable sampling
    hal.scheduler->delay(300);

    // Reading first sample
    curr_tick = *((uint64_t *)circle_buffer->get_page(circle_buffer->_virt_pages, curr_pointer));
    curr_pointer += 8;
    signal_states = *((uint64_t *)circle_buffer->get_page(circle_buffer->_virt_pages, curr_pointer));
    for (uint32_t i = 0; i < RCIN_RPI_CHN_NUM; ++i) {
        rc_channels[i].prev_tick = curr_tick;
        rc_channels[i].curr_signal = (signal_states & (1 << RcChnGpioTbl[i])) ? RCIN_RPI_SIG_HIGH
                                                                              : RCIN_RPI_SIG_LOW;
        rc_channels[i].last_signal = rc_channels[i].curr_signal;
    }
    curr_pointer += 8;

    set_num_channels(RCIN_RPI_CHN_NUM);

    _initialized = true;
}

// Processing signal
void RCInput_RPI::_timer_tick()