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Testing external clock detection and auto-switch

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Simplified audio spectrum computation and transfer
ACARS RX in debug mode
Disabled ABI warnings
Updated binary
This commit is contained in:
furrtek
2018-06-12 07:55:12 +01:00
parent dc5d6fef70
commit 609235b19f
30 changed files with 318 additions and 182 deletions
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firmware/baseband/proc_wfm_audio.cpp
+49 -41
View File
@@ -66,47 +66,57 @@ void WidebandFMAudio::execute(const buffer_c8_t& buffer) {
auto audio_2fs = audio_dec_2.execute(audio_4fs, work_audio_buffer);
// Input: 96kHz int16_t[64]
// audio_spectrum_decimator piles up 256 bytes before doing FFT computation
// This should send an AudioSpectrum every sample rate/buffer size/(256/64)/refresh scaler = 3072000/2048/4/8 = ~47 Hz
// audio_spectrum_decimator piles up 256 samples before doing FFT computation
// This sends an AudioSpectrum every: sample rate/buffer size/refresh period = 3072000/2048/50 = 30 Hz
// When audio_spectrum_timer expires, the audio spectrum computation is triggered
// 0~3: feed continuous audio
// 4~31: ignore, wrap at 31
if (!(refresh_timer & 0xF8)) {
for (size_t i = 0; i < 64; i++) {
complex_audio[i] = { (int16_t)(work_audio_buffer.p[i] / 32), (int16_t)0 };
}
audio_spectrum_decimator.feed(
complex_audio_buffer,
[this](const buffer_c16_t& data) {
this->post_message(data);
}
);
} else {
// Spread the FFT workload in time to avoid making the audio skip
// "8" comes from the log2() of the size of audio_spectrum: log2(256) = 8
if (fft_stage && (fft_stage <= 8)) {
fft_c_preswapped(audio_spectrum, fft_stage - 1, fft_stage);
fft_stage++;
} else if (fft_stage > 8) {
AudioSpectrum spectrum;
const size_t spectrum_end = spectrum.db.size();
for(size_t i=0; i<spectrum_end; i++) {
//const auto corrected_sample = spectrum_window_hamming_3(audio_spectrum, i);
const auto corrected_sample = audio_spectrum[i];
const auto mag2 = magnitude_squared(corrected_sample * (1.0f / 32768.0f));
const float db = mag2_to_dbv_norm(mag2);
constexpr float mag_scale = 5.0f;
const unsigned int v = (db * mag_scale) + 255.0f;
spectrum.db[i] = std::max(0U, std::min(255U, v));
}
fifo.in(spectrum);
fft_stage = 0;
}
audio_spectrum_timer++;
if (audio_spectrum_timer == 50) {
audio_spectrum_timer = 0;
audio_spectrum_state = FEED;
}
if (refresh_timer == 31)
refresh_timer = 0;
else
refresh_timer++;
switch (audio_spectrum_state) {
case FEED:
// Convert audio to "complex" just so the FFT can be done :/
for (size_t i = 0; i < 64; i++) {
complex_audio[i] = { (int16_t)(work_audio_buffer.p[i] / 32), (int16_t)0 };
}
audio_spectrum_decimator.feed(
complex_audio_buffer,
[this](const buffer_c16_t& data) {
this->post_message(data);
}
);
break;
case FFT:
// Spread the FFT workload in time to avoid making the audio skip
// "8" comes from the log2() of the size of audio_spectrum: log2(256) = 8
if (fft_step < 8) {
fft_c_preswapped(audio_spectrum, fft_step, fft_step + 1);
fft_step++;
} else {
const size_t spectrum_end = spectrum.db.size();
for(size_t i=0; i<spectrum_end; i++) {
//const auto corrected_sample = spectrum_window_hamming_3(audio_spectrum, i);
const auto corrected_sample = audio_spectrum[i];
const auto mag2 = magnitude_squared(corrected_sample * (1.0f / 32768.0f));
const float db = mag2_to_dbv_norm(mag2);
constexpr float mag_scale = 5.0f;
const unsigned int v = (db * mag_scale) + 255.0f;
spectrum.db[i] = std::max(0U, std::min(255U, v));
}
AudioSpectrumMessage message { &spectrum };
shared_memory.application_queue.push(message);
audio_spectrum_state = IDLE;
}
break;
default:
break;
}
/* 96kHz int16_t[64]
* -> FIR filter, <15kHz (0.156fs) pass, >19kHz (0.198fs) stop, gain of 1
@@ -121,7 +131,8 @@ void WidebandFMAudio::execute(const buffer_c8_t& buffer) {
void WidebandFMAudio::post_message(const buffer_c16_t& data) {
// This is called when audio_spectrum_decimator is filled up to 256 samples
fft_swap(data, audio_spectrum);
fft_stage = 1;
audio_spectrum_state = FFT;
fft_step = 0;
}
void WidebandFMAudio::on_message(const Message* const message) {
@@ -167,9 +178,6 @@ void WidebandFMAudio::configure(const WFMConfigureMessage& message) {
channel_spectrum.set_decimation_factor(1);
configured = true;
AudioSpectrumConfigMessage config_message { &fifo };
shared_memory.application_queue.push(config_message);
}
void WidebandFMAudio::capture_config(const CaptureConfigMessage& message) {