portapack-mayhem/firmware/application/tuning.cpp

81 lines
3.0 KiB
C++

/*
* Copyright (C) 2014 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 "tuning.hpp"
#include "utility.hpp"
namespace tuning {
namespace config {
// Low band <2170 Mhz:
constexpr rf::Frequency low_band_second_lo_frequency(const rf::Frequency target_frequency) {
return 2650'000'000 - (target_frequency / 7);
}
Config low_band(const rf::Frequency target_frequency) {
const rf::Frequency second_lo_frequency = low_band_second_lo_frequency(target_frequency);
const rf::Frequency first_lo_frequency = target_frequency + second_lo_frequency;
const bool mixer_invert = true;
return {first_lo_frequency, second_lo_frequency, rf::path::Band::Low, mixer_invert};
}
// Mid band 2170-2740 Mhz:
Config mid_band(const rf::Frequency target_frequency) {
const rf::Frequency second_lo_frequency = target_frequency;
const rf::Frequency first_lo_frequency = 0;
const bool mixer_invert = false;
return {first_lo_frequency, second_lo_frequency, rf::path::Band::Mid, mixer_invert};
}
// High band >2740 Mhz:
constexpr rf::Frequency high_band_second_lo_frequency(const rf::Frequency target_frequency) {
if (target_frequency < 3600'000'000)
return (2170'000'000 + (((target_frequency - 2740'000'000) * 57) / 86));
else if (target_frequency < 5100'000'000)
return (2350'000'000 + ((target_frequency - 3600'000'000) / 5));
else
return (2500'000'000 + ((target_frequency - 5100'000'000) / 9));
}
Config high_band(const rf::Frequency target_frequency) {
const rf::Frequency second_lo_frequency = high_band_second_lo_frequency(target_frequency);
const rf::Frequency first_lo_frequency = target_frequency - second_lo_frequency;
const bool mixer_invert = false;
return {first_lo_frequency, second_lo_frequency, rf::path::Band::High, mixer_invert};
}
Config create(const rf::Frequency target_frequency) {
/* TODO: This is some lame code. */
if (rf::path::band_low.contains(target_frequency)) {
return low_band(target_frequency);
} else if (rf::path::band_mid.contains(target_frequency)) {
return mid_band(target_frequency);
} else if (rf::path::band_high.contains(target_frequency)) {
return high_band(target_frequency);
} else {
return {};
}
}
} /* namespace config */
} /* namespace tuning */