ardupilot/libraries/RC_Channel/RC_Channels.cpp

/*
   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation, either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/*
 *       RC_Channels.cpp - class containing an array of RC_Channel objects
 *
 */

#include <stdlib.h>
#include <cmath>

#include <AP_HAL/AP_HAL.h>
extern const AP_HAL::HAL& hal;

#include <AP_Math/AP_Math.h>

#include "RC_Channel.h"

RC_Channel *RC_Channels::channels;
bool RC_Channels::has_new_overrides;
AP_Float *RC_Channels::override_timeout;

const AP_Param::GroupInfo RC_Channels::var_info[] = {
    // @Group: 1_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[0], "1_",  1, RC_Channels, RC_Channel),

    // @Group: 2_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[1], "2_",  2, RC_Channels, RC_Channel),

    // @Group: 3_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[2], "3_",  3, RC_Channels, RC_Channel),

    // @Group: 4_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[3], "4_",  4, RC_Channels, RC_Channel),

    // @Group: 5_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[4], "5_",  5, RC_Channels, RC_Channel),

    // @Group: 6_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[5], "6_",  6, RC_Channels, RC_Channel),

    // @Group: 7_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[6], "7_",  7, RC_Channels, RC_Channel),

    // @Group: 8_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[7], "8_",  8, RC_Channels, RC_Channel),

    // @Group: 9_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[8], "9_",  9, RC_Channels, RC_Channel),

    // @Group: 10_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[9], "10_", 10, RC_Channels, RC_Channel),

    // @Group: 11_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[10], "11_", 11, RC_Channels, RC_Channel),

    // @Group: 12_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[11], "12_", 12, RC_Channels, RC_Channel),

    // @Group: 13_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[12], "13_", 13, RC_Channels, RC_Channel),

    // @Group: 14_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[13], "14_", 14, RC_Channels, RC_Channel),

    // @Group: 15_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[14], "15_", 15, RC_Channels, RC_Channel),

    // @Group: 16_
    // @Path: RC_Channel.cpp
    AP_SUBGROUPINFO(obj_channels[15], "16_", 16, RC_Channels, RC_Channel),

    // @Param: _OVERRIDE_TIME
    // @DisplayName: RC override timeout
    // @Description: Timeout after which RC overrides will no longer be used, and RC input will resume, 0 will disable RC overrides
    // @User: Advanced
    // @Range: 0.0 120.0
    // @Units: s
    AP_GROUPINFO("_OVERRIDE_TIME", 32, RC_Channels, _override_timeout, 3.0),
    
    AP_GROUPEND
};


/*
  channels group object constructor
 */
RC_Channels::RC_Channels(void)
{
    channels = obj_channels;

    override_timeout = &_override_timeout;
    
    // set defaults from the parameter table
    AP_Param::setup_object_defaults(this, var_info);

    // setup ch_in on channels
    for (uint8_t i=0; i<NUM_RC_CHANNELS; i++) {
        channels[i].ch_in = i;
    }
}

uint16_t RC_Channels::get_radio_in(const uint8_t chan)
{
    if (chan >= NUM_RC_CHANNELS) {
        return 0;
    }
    return channels[chan].get_radio_in();
}

uint8_t RC_Channels::get_radio_in(uint16_t *chans, const uint8_t num_channels)
{
    uint8_t read_channels = MIN(num_channels, NUM_RC_CHANNELS);
    for (uint8_t i = 0; i < read_channels; i++) {
        chans[i] = channels[i].get_radio_in();
    }

    // clear any excess channels we couldn't read
    if (read_channels < num_channels) {
        memset(&chans[NUM_RC_CHANNELS], 0, sizeof(uint16_t) * (num_channels - read_channels));
    }

    return read_channels;
}

/*
  call read() and set_pwm() on all channels if there is new data
 */
bool
RC_Channels::read_input(void)
{
    if (!hal.rcin->new_input() && !has_new_overrides) {
        return false;
    }

    has_new_overrides = false;

    for (uint8_t i=0; i<NUM_RC_CHANNELS; i++) {
        channels[i].set_pwm(channels[i].read());
    }

    return true;
}

uint8_t RC_Channels::get_valid_channel_count(void)
{
    return MIN(NUM_RC_CHANNELS, hal.rcin->num_channels());
}

int16_t RC_Channels::get_receiver_rssi(void)
{
    return hal.rcin->get_rssi();
}

void RC_Channels::clear_overrides(void)
{
    for (uint8_t i = 0; i < NUM_RC_CHANNELS; i++) {
        channels[i].clear_override();
    }
    // we really should set has_new_overrides to true, and rerun read_input from
    // the vehicle code however doing so currently breaks the failsafe system on
    // copter and plane, RC_Channels needs to control failsafes to resolve this
}

void RC_Channels::set_override(const uint8_t chan, const int16_t value, const uint32_t timestamp_ms)
{
    if (chan < NUM_RC_CHANNELS) {
        channels[chan].set_override(value, timestamp_ms);
        has_new_overrides = true;
    }
}

bool RC_Channels::has_active_overrides()
{
    for (uint8_t i = 0; i < NUM_RC_CHANNELS; i++) {
        if (channels[i].has_override()) {
            return true;
        }
    }

    return false;
}

bool RC_Channels::receiver_bind(const int dsmMode)
{
    return hal.rcin->rc_bind(dsmMode);
}