portapack-mayhem/firmware/baseband/proc_ert.cpp
2024-02-10 16:56:50 +01:00

117 lines
3.6 KiB
C++

/*
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2023 Mark Thompson
*
* 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_ert.hpp"
#include "portapack_shared_memory.hpp"
#include "event_m4.hpp"
float ERTProcessor::abs(const complex8_t& v) {
// const int16_t r = v.real() - offset_i;
// const int16_t i = v.imag() - offset_q;
// const uint32_t r2 = r * r;
// const uint32_t i2 = i * i;
// const uint32_t r2_i2 = r2 + i2;
// return std::sqrt(static_cast<float>(r2_i2));
const float r = static_cast<float>(v.real()) - offset_i;
const float i = static_cast<float>(v.imag()) - offset_q;
const float r2 = r * r;
const float i2 = i * i;
const float r2_i2 = r2 + i2;
return std::sqrt(r2_i2);
}
void ERTProcessor::execute(const buffer_c8_t& buffer) {
/* 4.194304MHz, 2048 samples */
const complex8_t* src = &buffer.p[0];
const complex8_t* const src_end = &buffer.p[buffer.count];
average_i += src->real();
average_q += src->imag();
average_count++;
if (average_count == average_window) {
offset_i = static_cast<float>(average_i) / average_window;
offset_q = static_cast<float>(average_q) / average_window;
average_i = 0;
average_q = 0;
average_count = 0;
}
const float gain = 128 * samples_per_symbol;
const float k = 1.0f / gain;
while (src < src_end) {
float sum = 0.0f;
for (size_t i = 0; i < (samples_per_symbol / 2); i++) {
sum += abs(*(src++));
}
sum_half_period[1] = sum_half_period[0];
sum_half_period[0] = sum;
sum_period[2] = sum_period[1];
sum_period[1] = sum_period[0];
sum_period[0] = (sum_half_period[0] + sum_half_period[1]) * k;
manchester[2] = manchester[1];
manchester[1] = manchester[0];
manchester[0] = sum_period[2] - sum_period[0];
const auto data = manchester[0] - manchester[2];
clock_recovery(data);
}
}
void ERTProcessor::consume_symbol(
const float raw_symbol) {
const uint_fast8_t sliced_symbol = (raw_symbol >= 0.0f) ? 1 : 0;
scm_builder.execute(sliced_symbol);
scmplus_builder.execute(sliced_symbol);
idm_builder.execute(sliced_symbol);
}
void ERTProcessor::scm_handler(
const baseband::Packet& packet) {
const ERTPacketMessage message{ert::Packet::Type::SCM, packet};
shared_memory.application_queue.push(message);
}
void ERTProcessor::scmplus_handler(
const baseband::Packet& packet) {
const ERTPacketMessage message{ert::Packet::Type::SCMPLUS, packet};
shared_memory.application_queue.push(message);
}
void ERTProcessor::idm_handler(
const baseband::Packet& packet) {
const ERTPacketMessage message{ert::Packet::Type::IDM, packet};
shared_memory.application_queue.push(message);
}
int main() {
EventDispatcher event_dispatcher{std::make_unique<ERTProcessor>()};
event_dispatcher.run();
return 0;
}