portapack-mayhem/firmware/baseband/proc_adsbtx.cpp
furrtek 5a67a7080a ADS-B TX works well enough for dump1090 and gr-air-modes
Hooked ADS-B RX to baseband instead of debug IQ file, not tested
2017-07-23 12:20:32 +01:00

117 lines
2.8 KiB
C++

/*
* Copyright (C) 2014 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_adsbtx.hpp"
#include "portapack_shared_memory.hpp"
#include "sine_table_int8.hpp"
#include "event_m4.hpp"
#include <cstdint>
void ADSBTXProcessor::execute(const buffer_c8_t& buffer) {
// This is called at 4M/2048 = 1953Hz
// One pulse = 500ns = 2 samples
// One bit = 2 pulses = 1us = 4 samples
// Test this with ./dump1090 --freq 434000000 --gain 20
// Or ./dump1090 --freq 434000000 --gain 20 --interactive --net --net-http-port 8080 --net-beast
if (!configured) return;
/*if (terminate) {
for (size_t i = 0; i < buffer.count; i++) {
buffer.p[i] = { 0, 0 };
}
terminate--;
if (!terminate) {
message.done = true;
shared_memory.application_queue.push(message);
configured = false;
return;
}
} else {*/
for (size_t i = 0; i < buffer.count; i++) {
/*if (active) {
if (!sample) {
sample = 300;
if (bit_pos >= 112) {
active = false; // Stop
cur_bit = 0;
} else {
cur_bit = shared_memory.bb_data.data[bit_pos];
bit_pos++;
}
} else
sample--;
if (!preamble) {
if (sample == 150)
cur_bit ^= 1; // Invert
}
} else {*/
/*cur_bit = 0;
if (bit_pos >= 16384) {
configured = false;
message.done = true;
shared_memory.application_queue.push(message);
}*/
if (bit_pos >= (240 << 1)) {
configured = false;
terminate = 100;
cur_bit = 0;
} else {
cur_bit = shared_memory.bb_data.data[bit_pos >> 1];
bit_pos++;
}
//}
if (cur_bit) {
// Crude AM
buffer.p[i] = am_lut[phase & 3];
phase++;
} else {
buffer.p[i] = { 0, 0 };
}
}
//}
}
void ADSBTXProcessor::on_message(const Message* const p) {
const auto message = *reinterpret_cast<const ADSBConfigureMessage*>(p);
if (message.id == Message::ID::ADSBConfigure) {
bit_pos = 0;
phase = 0;
active = true;
configured = true;
terminate = 0;
}
}
int main() {
EventDispatcher event_dispatcher { std::make_unique<ADSBTXProcessor>() };
event_dispatcher.run();
return 0;
}