portapack-mayhem/firmware/baseband/proc_wideband_spectrum.cpp

/*
 * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
 *
 * 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_wideband_spectrum.hpp"

#include "event_m4.hpp"

#include <cstdint>
#include <cstddef>

#include <array>

void WidebandSpectrum::execute(const buffer_c8_t& buffer) {
    // 2048 complex8_t samples per buffer.
    // 102.4us per buffer. 20480 instruction cycles per buffer.

    if (!configured) return;

    if (phase == 0) {
        std::fill(spectrum.begin(), spectrum.end(), 0);
    }

    for (size_t i = 0; i < spectrum.size(); i++) {
        // TODO: Removed window-presum windowing, due to lack of available code RAM.
        // TODO: Apply window to improve spectrum bin sidelobes.
        spectrum[i] += buffer.p[i + 0];
        spectrum[i] += buffer.p[i + 1024];
    }

    if (phase == trigger) {
        const buffer_c16_t buffer_c16{
            spectrum.data(),
            spectrum.size(),
            buffer.sampling_rate};
        channel_spectrum.feed(
            buffer_c16,
            0, 0, 0);
        phase = 0;
    } else {
        phase++;
    }
}

void WidebandSpectrum::on_message(const Message* const msg) {
    const WidebandSpectrumConfigMessage message = *reinterpret_cast<const WidebandSpectrumConfigMessage*>(msg);

    switch (msg->id) {
        case Message::ID::UpdateSpectrum:
        case Message::ID::SpectrumStreamingConfig:
            channel_spectrum.on_message(msg);
            break;

        case Message::ID::WidebandSpectrumConfig:
            baseband_fs = message.sampling_rate;
            trigger = message.trigger;
            baseband_thread.set_sampling_rate(baseband_fs);
            phase = 0;
            configured = true;
            break;

        default:
            break;
    }
}

int main() {
    EventDispatcher event_dispatcher{std::make_unique<WidebandSpectrum>()};
    event_dispatcher.run();
    return 0;
}