mayhem-firmware/firmware/baseband/proc_sonde.cpp

/*
 * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
 * Copyright (C) 2017 Furrtek
 *
 * This file is part of PortaPack.
 *
 * 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 2, 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; see the file COPYING.  If not, write to
 * the Free Software Foundation, Inc., 51 Franklin Street,
 * Boston, MA 02110-1301, USA.
 */

#include "proc_sonde.hpp"

#include "dsp_fir_taps.hpp"

#include "event_m4.hpp"

#include "audio_output.hpp"

SondeProcessor::SondeProcessor() {
    decim_0.configure(taps_11k0_decim_0.taps, 33554432);
    decim_1.configure(taps_11k0_decim_1.taps, 131072);

    audio_output.configure(false);

    tone_gen.configure(BEEP_BASE_FREQ, 1.0, ToneGen::tone_type::sine, AUDIO_SAMPLE_RATE);
}

void SondeProcessor::execute(const buffer_c8_t& buffer) {
    /* 2.4576MHz, 2048 samples */

    const auto decim_0_out = decim_0.execute(buffer, dst_buffer);
    const auto decim_1_out = decim_1.execute(decim_0_out, dst_buffer);
    const auto decimator_out = decim_1_out;

    /* 38.4kHz, 32 samples */
    feed_channel_stats(decimator_out);

    for (size_t i = 0; i < decimator_out.count; i++) {
        if (mf.execute_once(decimator_out.p[i])) {
            clock_recovery_fsk_9600(mf.get_output());
            clock_recovery_fsk_4800(mf.get_output());
        }
    }

    if (pitch_rssi_enabled) {
        if (beep_play) {
            // if we let the buffer underrun, for some reason
            // once it starts looping it ignores zero (silence)
            // samples, so we need to keep feeding the buffer
            // and not be able to take advantage of the circular
            // buffer loop:
            // beep_play = false;
            generate_beep();
        }

        if (silence_play) {
            // silence_play = false;
            generate_silence();
        }
    }
}

void SondeProcessor::on_message(const Message* const msg) {
    switch (msg->id) {
        case Message::ID::RequestSignal:
            if ((*reinterpret_cast<const RequestSignalMessage*>(msg)).signal == RequestSignalMessage::Signal::BeepRequest) {
                float rssi_ratio = (float)last_rssi / (float)RSSI_CEILING;
                int beep_duration = 0;

                if (rssi_ratio <= PROPORTIONAL_BEEP_THRES) {
                    beep_duration = BEEP_MIN_DURATION;
                } else if (rssi_ratio < 1) {
                    beep_duration = (int)rssi_ratio * BEEP_DURATION_RANGE + BEEP_MIN_DURATION;
                } else {
                    beep_duration = BEEP_DURATION_RANGE + BEEP_MIN_DURATION;
                }

                play_beep();
                chThdSleepMilliseconds(beep_duration);
                stop_beep();
            }
            break;

        case Message::ID::PitchRSSIConfigure:
            pitch_rssi_config(*reinterpret_cast<const PitchRSSIConfigureMessage*>(msg));
            break;

        default:
            break;
    }
}

void SondeProcessor::play_beep() {
    beep_play = true;
    silence_play = false;
}

void SondeProcessor::stop_beep() {
    beep_play = false;
    silence_play = true;
}

void SondeProcessor::generate_beep() {
    // here we let the samples be created using the ToneGen class:

    for (uint8_t i = 0; i < sizeof(audio_buffer.p); i++) {
        audio_buffer.p[i] = (int16_t)((tone_gen.process(0) >> 16) & 0x0000FFFF);
    }

    audio_output.write(audio_buffer);
}

void SondeProcessor::generate_silence() {
    for (uint8_t i = 0; i < sizeof(audio_buffer.p); i++) {
        audio_buffer.p[i] = 0;
    }

    audio_output.write(audio_buffer);
}

void SondeProcessor::pitch_rssi_config(const PitchRSSIConfigureMessage& message) {
    pitch_rssi_enabled = message.enabled;

    uint32_t freq = (int)((float)message.rssi * (float)RSSI_PITCH_WEIGHT + (float)BEEP_BASE_FREQ);

    last_rssi = message.rssi;
    tone_gen.configure(freq, 1.0, ToneGen::tone_type::sine, AUDIO_SAMPLE_RATE);
}

int main() {
    EventDispatcher event_dispatcher{std::make_unique<SondeProcessor>()};
    event_dispatcher.run();

    return 0;
}