mirror of
https://github.com/eried/portapack-mayhem.git
synced 2024-10-01 01:26:06 -04:00
120 lines
3.7 KiB
C++
120 lines
3.7 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 "proc_fsk.hpp"
|
|
|
|
#include "portapack_shared_memory.hpp"
|
|
|
|
#include "i2s.hpp"
|
|
using namespace lpc43xx;
|
|
|
|
FSKProcessor::FSKProcessor(
|
|
MessageHandlerMap& message_handlers
|
|
) : message_handlers(message_handlers)
|
|
{
|
|
message_handlers.register_handler(Message::ID::FSKConfiguration,
|
|
[this](const Message* const p) {
|
|
auto m = reinterpret_cast<const FSKConfigurationMessage*>(p);
|
|
this->configure(m->configuration);
|
|
}
|
|
);
|
|
}
|
|
|
|
FSKProcessor::~FSKProcessor() {
|
|
message_handlers.unregister_handler(Message::ID::FSKConfiguration);
|
|
}
|
|
|
|
void FSKProcessor::configure(const FSKConfiguration new_configuration) {
|
|
// TODO: Matched filter characteristics are hard-coded for the moment. YUCK!
|
|
clock_recovery.configure(sampling_rate / 4, new_configuration.symbol_rate);
|
|
packet_builder.configure(
|
|
{ new_configuration.access_code, new_configuration.access_code_length, new_configuration.access_code_tolerance },
|
|
{ new_configuration.unstuffing_pattern, new_configuration.unstuffing_length }
|
|
);
|
|
}
|
|
|
|
void FSKProcessor::execute(buffer_c8_t buffer) {
|
|
/* 2.4576MHz, 2048 samples */
|
|
|
|
auto decimator_out = decimator.execute(buffer);
|
|
|
|
/* 153.6kHz, 128 samples */
|
|
|
|
const buffer_c16_t work_baseband_buffer {
|
|
(complex16_t*)decimator_out.p,
|
|
decimator_out.count
|
|
};
|
|
|
|
/* 153.6kHz complex<int16_t>[128]
|
|
* -> FIR filter, <?kHz (?fs) pass, gain 1.0
|
|
* -> 76.8kHz int16_t[64] */
|
|
auto channel = channel_filter.execute(decimator_out, work_baseband_buffer);
|
|
|
|
/* 76.8kHz, 64 samples */
|
|
feed_channel_stats(channel);
|
|
feed_channel_spectrum(
|
|
channel,
|
|
decimator_out.sampling_rate * channel_filter_taps.pass_frequency_normalized,
|
|
decimator_out.sampling_rate * channel_filter_taps.stop_frequency_normalized
|
|
);
|
|
|
|
// 76.8k
|
|
|
|
// TODO: Factor out this hidden decimation magic.
|
|
for(size_t i=0; i<channel.count; i+=4) {
|
|
// TODO: No idea why implicit cast int16_t->float is not allowed.
|
|
const std::complex<float> sample {
|
|
static_cast<float>(channel.p[i].real()),
|
|
static_cast<float>(channel.p[i].imag())
|
|
};
|
|
mf_0.execute_once(sample);
|
|
if( mf_1.execute_once(sample) ) {
|
|
const auto value_0 = mf_0.get_output();
|
|
const float mag_0 = std::sqrt(value_0.real() * value_0.real() + value_0.imag() * value_0.imag());
|
|
const auto value_1 = mf_1.get_output();
|
|
const float mag_1 = std::sqrt(value_1.real() * value_1.real() + value_1.imag() * value_1.imag());
|
|
const float diff = mag_1 - mag_0;
|
|
clock_recovery(diff);
|
|
}
|
|
}
|
|
|
|
i2s::i2s0::tx_mute();
|
|
}
|
|
|
|
void FSKProcessor::consume_symbol(
|
|
const float raw_symbol
|
|
) {
|
|
const uint_fast8_t sliced_symbol = (raw_symbol >= 0.0f) ? 1 : 0;
|
|
const auto decoded_symbol = nrzi_decode(sliced_symbol);
|
|
|
|
packet_builder.execute(decoded_symbol);
|
|
}
|
|
|
|
void FSKProcessor::payload_handler(
|
|
const std::bitset<1024>& payload,
|
|
const size_t bits_received
|
|
) {
|
|
FSKPacketMessage message;
|
|
message.packet.payload = payload;
|
|
message.packet.bits_received = bits_received;
|
|
shared_memory.application_queue.push(message);
|
|
}
|