portapack-mayhem/firmware/baseband/proc_tones.cpp

/*
 * Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
 * Copyright (C) 2016 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_tones.hpp"
#include "sine_table_int8.hpp"
#include "event_m4.hpp"

#include <cstdint>

// This is called at 1536000/2048 = 750Hz
void TonesProcessor::execute(const buffer_c8_t& buffer) {
    if (!configured) return;

    ai = 0;

    for (size_t i = 0; i < buffer.count; i++) {
        // Tone generation at full samplerate
        if (silence_count) {
            // Just occupy channel with carrier
            silence_count--;
            if (!silence_count) {
                sample_count = 0;
                tone_a_phase = 0;
                tone_b_phase = 0;
            }
            tone_sample = 0;
            re = 0;
            im = 0;
        } else {
            if (!sample_count) {
                digit = shared_memory.bb_data.tones_data.message[digit_pos];
                if (digit_pos >= message_length) {
                    configured = false;
                    txprogress_message.done = true;
                    shared_memory.application_queue.push(txprogress_message);
                    return;
                } else {
                    txprogress_message.progress = digit_pos;  // Inform UI about progress
                    txprogress_message.done = false;
                    shared_memory.application_queue.push(txprogress_message);
                }

                digit_pos++;

                if (digit >= 32) {  // || (tone_deltas[digit] == 0)
                    sample_count = shared_memory.bb_data.tones_data.silence;
                } else {
                    if (!dual_tone) {
                        tone_a_delta = tone_deltas[digit];
                    } else {
                        tone_a_delta = tone_deltas[digit << 1];
                        tone_b_delta = tone_deltas[(digit << 1) + 1];
                    }
                    sample_count = tone_durations[digit];
                }
            } else {
                sample_count--;
            }

            // Ugly
            if ((digit >= 32) || (tone_deltas[digit] == 0)) {
                tone_sample = 0;
            } else {
                if (!dual_tone) {
                    tone_sample = (sine_table_i8[(tone_a_phase & 0xFF000000U) >> 24]);
                    tone_a_phase += tone_a_delta;
                } else {
                    tone_sample = sine_table_i8[(tone_a_phase & 0xFF000000U) >> 24] >> 1;
                    tone_sample += sine_table_i8[(tone_b_phase & 0xFF000000U) >> 24] >> 1;

                    tone_a_phase += tone_a_delta;
                    tone_b_phase += tone_b_delta;
                }
            }

            // FM
            delta = tone_sample * fm_delta;

            phase += delta;
            sphase = phase + (64 << 24);

            re = (sine_table_i8[(sphase & 0xFF000000U) >> 24]);
            im = (sine_table_i8[(phase & 0xFF000000U) >> 24]);
        }

        // Headphone output sample generation: 1536000/24000 = 64
        if (audio_out) {
            if (!as) {
                as = 64;
                audio_buffer.p[ai++] = tone_sample * 128;
            } else {
                as--;
            }
        }

        buffer.p[i] = {re, im};
    }

    if (audio_out) audio_output.write(audio_buffer);
}

void TonesProcessor::on_message(const Message* const p) {
    const auto message = *reinterpret_cast<const TonesConfigureMessage*>(p);
    if (message.id == Message::ID::TonesConfigure) {
        message_length = message.tone_count;

        if (message_length) {
            silence_count = message.pre_silence;  // In samples
            for (uint8_t c = 0; c < 32; c++) {
                tone_deltas[c] = shared_memory.bb_data.tones_data.tone_defs[c].delta;
                tone_durations[c] = shared_memory.bb_data.tones_data.tone_defs[c].duration;
            }
            fm_delta = message.fm_delta * (0xFFFFFFULL / 1536000);
            audio_out = message.audio_out;
            dual_tone = message.dual_tone;

            if (audio_out) audio_output.configure(false);

            txprogress_message.done = false;
            txprogress_message.progress = 0;

            digit_pos = 0;
            sample_count = 0;
            tone_a_phase = 0;
            tone_b_phase = 0;
            as = 0;

            configured = true;
        } else {
            configured = false;
            txprogress_message.done = true;
            shared_memory.application_queue.push(txprogress_message);
        }
    }
}

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