Nrf24l01 demodulation (#338)

* NRF demodulation

* Update ui_navigation.cpp
This commit is contained in:
Erwin Ried 2020-04-20 06:45:28 +02:00 committed by GitHub
parent 3dfbdc844c
commit d95bda65ce
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12 changed files with 719 additions and 0 deletions

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@ -217,6 +217,7 @@ set(CPPSRC
apps/ui_adsb_rx.cpp
apps/ui_adsb_tx.cpp
apps/ui_afsk_rx.cpp
apps/ui_nrf_rx.cpp
apps/ui_aprs_tx.cpp
apps/ui_bht_tx.cpp
apps/ui_coasterp.cpp

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@ -0,0 +1,165 @@
/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2017 Furrtek
* Copyright (C) 2020 Shao
*
* 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 "ui_nrf_rx.hpp"
#include "ui_modemsetup.hpp"
#include "modems.hpp"
#include "audio.hpp"
#include "rtc_time.hpp"
#include "baseband_api.hpp"
#include "string_format.hpp"
#include "portapack_persistent_memory.hpp"
using namespace portapack;
using namespace modems;
namespace ui {
void NRFRxView::focus() {
field_frequency.focus();
}
void NRFRxView::update_freq(rf::Frequency f) {
receiver_model.set_tuning_frequency(f);
}
NRFRxView::NRFRxView(NavigationView& nav) {
baseband::run_image(portapack::spi_flash::image_tag_nrf_rx);
add_children({
&rssi,
&channel,
&field_rf_amp,
&field_lna,
&field_vga,
&field_frequency,
&text_debug,
&button_modem_setup,
&record_view,
&console
});
// DEBUG
record_view.on_error = [&nav](std::string message) {
nav.display_modal("Error", message);
};
record_view.set_sampling_rate(24000);
// Auto-configure modem for LCR RX (will be removed later)
update_freq(2480000000);
auto def_bell202 = &modem_defs[0];
persistent_memory::set_modem_baudrate(def_bell202->baudrate);
serial_format_t serial_format;
serial_format.data_bits = 7;
serial_format.parity = EVEN;
serial_format.stop_bits = 1;
serial_format.bit_order = LSB_FIRST;
persistent_memory::set_serial_format(serial_format);
field_frequency.set_value(receiver_model.tuning_frequency());
field_frequency.set_step(100);
field_frequency.on_change = [this](rf::Frequency f) {
update_freq(f);
};
field_frequency.on_edit = [this, &nav]() {
auto new_view = nav.push<FrequencyKeypadView>(receiver_model.tuning_frequency());
new_view->on_changed = [this](rf::Frequency f) {
update_freq(f);
field_frequency.set_value(f);
};
};
button_modem_setup.on_select = [&nav](Button&) {
nav.push<ModemSetupView>();
};
// Auto-configure modem for LCR RX (will be removed later)
baseband::set_nrf(persistent_memory::modem_baudrate(), 8, 0, false);
audio::set_rate(audio::Rate::Hz_24000);
audio::output::start();
receiver_model.set_sampling_rate(4000000);
receiver_model.set_baseband_bandwidth(4000000);
receiver_model.set_modulation(ReceiverModel::Mode::WidebandFMAudio);
receiver_model.enable();
}
void NRFRxView::on_data(uint32_t value, bool is_data) {
//std::string str_console = "\x1B";
std::string str_console = "";
if (is_data) {
// Colorize differently after message splits
//str_console += (char)((console_color & 3) + 9);
//value &= 0xFF; // ABCDEFGH
//value = ((value & 0xF0) >> 4) | ((value & 0x0F) << 4); // EFGHABCD
//value = ((value & 0xCC) >> 2) | ((value & 0x33) << 2); // GHEFCDAB
//value = ((value & 0xAA) >> 1) | ((value & 0x55) << 1); // HGFEDCBA
//value &= 0x7F; // Ignore parity, which is the MSB now
//if ((value >= 32) && (value < 127)) {
// str_console += (char)value; // Printable
//}
//str_console += (char)'A';
//str_console += (char)value;
//str_console += "[" + to_string_hex(value, 2) + "]";
str_console += " " + to_string_hex(value, 2) ;
console.write(str_console);
/*if ((value != 0x7F) && (prev_value == 0x7F)) {
// Message split
console.writeln("");
console_color++;
}*/
//prev_value = value;
} else {
// Baudrate estimation
//text_debug.set("~" + to_string_dec_uint(value));
if (value == 'A')
{console.write("addr:");}
else if (value == 'B')
{console.write(" data:");}
else if (value == 'C')
{
console.writeln("");
console.writeln("");
}
//console.writeln("");
}
}
NRFRxView::~NRFRxView() {
audio::output::stop();
receiver_model.disable();
baseband::shutdown();
}
} /* namespace ui */

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@ -0,0 +1,107 @@
/*
* Copyright (C) 2014 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2017 Furrtek
* Copyright (C) 2020 Shao
*
* 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.
*/
#ifndef __UI_NRF_RX_H__
#define __UI_NRF_RX_H__
#include "ui.hpp"
#include "ui_navigation.hpp"
#include "ui_receiver.hpp"
#include "ui_record_view.hpp" // DEBUG
#include "utility.hpp"
namespace ui {
class NRFRxView : public View {
public:
NRFRxView(NavigationView& nav);
~NRFRxView();
void focus() override;
std::string title() const override { return "NRF RX"; };
private:
void on_data(uint32_t value, bool is_data);
uint8_t console_color { 0 };
uint32_t prev_value { 0 };
std::string str_log { "" };
RFAmpField field_rf_amp {
{ 13 * 8, 0 * 16 }
};
LNAGainField field_lna {
{ 15 * 8, 0 * 16 }
};
VGAGainField field_vga {
{ 18 * 8, 0 * 16 }
};
RSSI rssi {
{ 21 * 8, 0, 6 * 8, 4 },
};
Channel channel {
{ 21 * 8, 5, 6 * 8, 4 },
};
FrequencyField field_frequency {
{ 0 * 8, 0 * 16 },
};
Text text_debug {
{ 0 * 8, 1 * 16, 10 * 8, 16 },
"DEBUG"
};
Button button_modem_setup {
{ 12 * 8, 1 * 16, 96, 24 },
"Modem setup"
};
// DEBUG
RecordView record_view {
{ 0 * 8, 3 * 16, 30 * 8, 1 * 16 },
u"AFS_????", RecordView::FileType::WAV, 4096, 4
};
Console console {
{ 0, 4 * 16, 240, 240 }
};
void update_freq(rf::Frequency f);
//void on_data_afsk(const AFSKDataMessage& message);
MessageHandlerRegistration message_handler_packet {
Message::ID::AFSKData,
[this](Message* const p) {
const auto message = static_cast<const AFSKDataMessage*>(p);
this->on_data(message->value, message->is_data);
}
};
};
} /* namespace ui */
#endif/*__UI_NRF_RX_H__*/

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@ -130,6 +130,16 @@ void set_afsk(const uint32_t baudrate, const uint32_t word_length, const uint32_
send_message(&message);
}
void set_nrf(const uint32_t baudrate, const uint32_t word_length, const uint32_t trigger_value, const bool trigger_word) {
const NRFRxConfigureMessage message {
baudrate,
word_length,
trigger_value,
trigger_word
};
send_message(&message);
}
void set_afsk_data(const uint32_t afsk_samples_per_bit, const uint32_t afsk_phase_inc_mark, const uint32_t afsk_phase_inc_space,
const uint8_t afsk_repeat, const uint32_t afsk_bw, const uint8_t symbol_count) {
const AFSKTxConfigureMessage message {

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@ -68,6 +68,7 @@ void set_afsk_data(const uint32_t afsk_samples_per_bit, const uint32_t afsk_phas
const uint8_t afsk_repeat, const uint32_t afsk_bw, const uint8_t symbol_count);
void kill_afsk();
void set_afsk(const uint32_t baudrate, const uint32_t word_length, const uint32_t trigger_value, const bool trigger_word);
void set_nrf(const uint32_t baudrate, const uint32_t word_length, const uint32_t trigger_value, const bool trigger_word);
void set_ook_data(const uint32_t stream_length, const uint32_t samples_per_bit, const uint8_t repeat,
const uint32_t pause_symbols);
void set_fsk_data(const uint32_t stream_length, const uint32_t samples_per_bit, const uint32_t shift,

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@ -1503,6 +1503,28 @@ static constexpr Bitmap bitmap_icon_replay {
{ 16, 16 }, bitmap_icon_replay_data
};
static constexpr uint8_t bitmap_icon_nrf_data[] = {
0x00, 0x00,
0x00, 0x00,
0x00, 0x00,
0x07, 0xE0,
0x05, 0x20,
0xCC, 0x33,
0xF4, 0x2F,
0xE6, 0x67,
0xE2, 0x47,
0x36, 0x5C,
0x0E, 0xE0,
0x06, 0x60,
0x00, 0x00,
0x00, 0x00,
0x00, 0x00,
0x00, 0x00,
};
static constexpr Bitmap bitmap_icon_nrf {
{ 16, 16 }, bitmap_icon_nrf_data
};
static constexpr uint8_t bitmap_sig_sine_data[] = {
0x00, 0x00, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00,

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@ -34,6 +34,7 @@
#include "ui_adsb_rx.hpp"
#include "ui_adsb_tx.hpp"
#include "ui_afsk_rx.hpp"
#include "ui_nrf_rx.hpp"
#include "ui_aprs_tx.hpp"
#include "ui_bht_tx.hpp"
#include "ui_coasterp.hpp"
@ -347,6 +348,7 @@ ReceiversMenuView::ReceiversMenuView(NavigationView& nav) {
{ "ACARS", ui::Color::yellow(), &bitmap_icon_adsb, [&nav](){ nav.push<ACARSAppView>(); }, },
{ "AIS Boats", ui::Color::green(), &bitmap_icon_ais, [&nav](){ nav.push<AISAppView>(); } },
{ "AFSK", ui::Color::yellow(), &bitmap_icon_receivers, [&nav](){ nav.push<AFSKRxView>(); } },
{ "NRF", ui::Color::yellow(), &bitmap_icon_nrf, [&nav](){ nav.push<NRFRxView>(); } },
{ "Audio", ui::Color::green(), &bitmap_icon_speaker, [&nav](){ nav.push<AnalogAudioView>(); } },
{ "ERT Meter", ui::Color::green(), &bitmap_icon_ert, [&nav](){ nav.push<ERTAppView>(); } },
{ "POCSAG", ui::Color::green(), &bitmap_icon_pocsag, [&nav](){ nav.push<POCSAGAppView>(); } },

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@ -311,6 +311,12 @@ set(MODE_CPPSRC
proc_afskrx.cpp
)
DeclareTargets(PAFR afskrx)
### NRF RX
set(MODE_CPPSRC
proc_nrfrx.cpp
)
DeclareTargets(PNRR nrfrx)
### AIS

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@ -0,0 +1,286 @@
/*
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2016 Furrtek
* Copyright (C) 2020 Shao
*
* 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_nrfrx.hpp"
#include "portapack_shared_memory.hpp"
#include "event_m4.hpp"
void NRFRxProcessor::execute(const buffer_c8_t& buffer) {
if (!configured) return;
// FM demodulation
const auto decim_0_out = decim_0.execute(buffer, dst_buffer);
feed_channel_stats(decim_0_out);
auto audio_oversampled = demod.execute(decim_0_out, work_audio_buffer);
// Audio signal processing
for (size_t c = 0; c < audio_oversampled.count; c++) {
int result;
int g_srate = 4; //4 for 250KPS
//int g_srate = 1; //1 for 1MPS, not working yet
int32_t current_sample = audio_oversampled.p[c]; //if I directly use this, some results can pass crc but not correct.
rb_head++;
rb_head=(rb_head)%RB_SIZE;
rb_buf[rb_head] = current_sample;
skipSamples = skipSamples - 1;
if (skipSamples<1)
{
int32_t threshold_tmp=0;
for (int c=0;c<8*g_srate;c++)
{
threshold_tmp = threshold_tmp + (int32_t)rb_buf[(rb_head+c)%RB_SIZE];
}
g_threshold = (int32_t)threshold_tmp/(8*g_srate);
int transitions=0;
if (rb_buf[(rb_head + 9*g_srate)%RB_SIZE] > g_threshold)
{
for (int c=0;c<8;c++)
{
if (rb_buf[(rb_head + c*g_srate)%RB_SIZE] > rb_buf[(rb_head + (c+1)*g_srate)%RB_SIZE])
transitions = transitions + 1;
}
}
else
{
for (int c=0;c<8;c++)
{
if (rb_buf[(rb_head + c*g_srate)%RB_SIZE] < rb_buf[(rb_head + (c+1)*g_srate)%RB_SIZE])
transitions = transitions + 1;
}
}
bool packet_detected=false;
//if ( transitions==4 && abs(g_threshold)<15500)
if ( transitions==4 && abs(g_threshold)<15500)
{
int packet_length = 0;
uint8_t tmp_buf[10];
uint8_t packet_data[500];
uint8_t packet_packed[50];
uint16_t pcf;
uint32_t packet_crc;
uint32_t calced_crc;
uint64_t packet_addr_l;
/* extract address */
packet_addr_l=0;
for (int t=0;t<5;t++)
{
bool current_bit;
uint8_t byte=0;
for (int c=0;c<8;c++)
{
if (rb_buf[(rb_head+(1*8+t*8+c)*g_srate)%RB_SIZE] > g_threshold)
current_bit = true;
else
current_bit = false;
byte |= current_bit << (7-c);
}
tmp_buf[t]=byte;
}
for (int t=0;t<5;t++) packet_addr_l|=((uint64_t)tmp_buf[t])<<(4-t)*8;
//channel_number = 26;
/* extract pcf */
for (int t=0;t<2;t++)
{
bool current_bit;
uint8_t byte=0;
for (int c=0;c<8;c++)
{
if (rb_buf[(rb_head+(6*8+t*8+c)*g_srate)%RB_SIZE] > g_threshold)
current_bit = true;
else
current_bit = false;
byte |= current_bit << (7-c);
}
tmp_buf[t]=byte;
}
pcf = tmp_buf[0]<<8 | tmp_buf[1];
pcf >>=7;
/* extract packet length, avoid excessive length packets */
if(packet_length == 0)
packet_length=(int)pcf>>3;
if (packet_length>32)
packet_detected = false;
/* extract data */
for (int t=0;t<packet_length;t++)
{
bool current_bit;
uint8_t byte=0;
for (int c=0;c<8;c++)
{
if (rb_buf[(rb_head+(6*8+9+t*8+c)*g_srate)%RB_SIZE] > g_threshold)
current_bit = true;
else
current_bit = false;
byte |= current_bit << (7-c);
}
packet_data[t]=byte;
}
/* Prepare packed bit stream for CRC calculation */
uint64_t packet_header=packet_addr_l;
packet_header<<=9;
packet_header|=pcf;
for (int c=0;c<7;c++){
packet_packed[c]=(packet_header>>((6-c)*8))&0xFF;
}
for (int c=0;c<packet_length;c++){
packet_packed[c+7]=packet_data[c];
}
/* calculate packet crc */
const uint8_t* data = packet_packed;
size_t data_len = 7+packet_length;
bool bit;
uint8_t cc;
uint_fast16_t crc=0x3C18;
while (data_len--) {
cc = *data++;
for (uint8_t i = 0x80; i > 0; i >>= 1)
{
bit = crc & 0x8000;
if (cc & i)
{
bit = !bit;
}
crc <<= 1;
if (bit)
{
crc ^= 0x1021;
}
}
crc &= 0xffff;
}
calced_crc = (uint16_t)(crc & 0xffff);
/* extract crc */
for (int t=0;t<2;t++)
{
bool current_bit;
uint8_t byte=0;
for (int c=0;c<8;c++)
{
if (rb_buf[(rb_head+((6+packet_length)*8+9+t*8+c)*g_srate)%RB_SIZE] > g_threshold)
current_bit = true;
else
current_bit = false;
byte |= current_bit << (7-c);
}
tmp_buf[t]=byte;
}
packet_crc = tmp_buf[0]<<8 | tmp_buf[1];
/* NRF24L01+ packet found, dump information */
//if (packet_addr_l==0xE7E7E7E7)
if (packet_crc==calced_crc)
{
data_message.is_data = false;
data_message.value = 'A';
shared_memory.application_queue.push(data_message);
data_message.is_data = true;
data_message.value = packet_addr_l;
shared_memory.application_queue.push(data_message);
for (int c=0;c<7;c++)
{
data_message.is_data = true;
data_message.value = packet_addr_l >> 8;
shared_memory.application_queue.push(data_message);
}
/*data_message.is_data = true;
data_message.value = packet_addr_l;
shared_memory.application_queue.push(data_message);
data_message.is_data = true;
data_message.value = packet_addr_l >> 8;
shared_memory.application_queue.push(data_message);*/
data_message.is_data = false;
data_message.value = 'B';
shared_memory.application_queue.push(data_message);
for (int c=0;c<packet_length;c++)
{
data_message.is_data = true;
data_message.value = packet_data[c];
shared_memory.application_queue.push(data_message);
}
data_message.is_data = false;
data_message.value = 'C';
shared_memory.application_queue.push(data_message);
packet_detected = true;
}
else
packet_detected = false;
}
if (packet_detected)
{
skipSamples=20;
}
}
}
}
void NRFRxProcessor::on_message(const Message* const message) {
if (message->id == Message::ID::NRFRxConfigure)
configure(*reinterpret_cast<const NRFRxConfigureMessage*>(message));
}
void NRFRxProcessor::configure(const NRFRxConfigureMessage& message) {
decim_0.configure(taps_200k_wfm_decim_0.taps, 33554432);
decim_1.configure(taps_200k_wfm_decim_1.taps, 131072);
demod.configure(audio_fs, 5000);
configured = true;
}
int main() {
EventDispatcher event_dispatcher { std::make_unique<NRFRxProcessor>() };
event_dispatcher.run();
return 0;
}

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@ -0,0 +1,96 @@
/*
* Copyright (C) 2015 Jared Boone, ShareBrained Technology, Inc.
* Copyright (C) 2016 Furrtek
* Copyright (C) 2020 Shao
*
* 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.
*/
#ifndef __PROC_NRFRX_H__
#define __PROC_NRFRX_H__
#include "baseband_processor.hpp"
#include "baseband_thread.hpp"
#include "rssi_thread.hpp"
#include "dsp_decimate.hpp"
#include "dsp_demodulate.hpp"
#include "audio_output.hpp"
#include "fifo.hpp"
#include "message.hpp"
class NRFRxProcessor : public BasebandProcessor {
public:
void execute(const buffer_c8_t& buffer) override;
void on_message(const Message* const message) override;
private:
static constexpr size_t baseband_fs = 4000000;
static constexpr size_t audio_fs = baseband_fs / 8 / 8 / 2;
BasebandThread baseband_thread { baseband_fs, this, NORMALPRIO + 20, baseband::Direction::Receive };
RSSIThread rssi_thread { NORMALPRIO + 10 };
std::array<complex16_t, 512> dst { };
const buffer_c16_t dst_buffer {
dst.data(),
dst.size()
};
std::array<complex16_t, 512> spectrum { };
const buffer_c16_t spectrum_buffer {
spectrum.data(),
spectrum.size()
};
const buffer_s16_t work_audio_buffer {
(int16_t*)dst.data(),
sizeof(dst) / sizeof(int16_t)
};
// Array size ok down to 375 bauds (24000 / 375)
std::array<int32_t, 64> delay_line { 0 };
std::array<int16_t, 1000> rb_buf { 0 };
/*dsp::decimate::FIRC8xR16x24FS4Decim8 decim_0 { };
dsp::decimate::FIRC16xR16x32Decim8 decim_1 { };
dsp::decimate::FIRAndDecimateComplex channel_filter { };*/
dsp::decimate::FIRC8xR16x24FS4Decim4 decim_0 { };
dsp::decimate::FIRC16xR16x16Decim2 decim_1 { };
dsp::demodulate::FM demod { };
int rb_head {-1};
int32_t g_threshold {0};
//uint8_t g_srate {8};
uint8_t channel_number {38};
int skipSamples {1000};
int RB_SIZE {1000};
bool configured { false };
void configure(const NRFRxConfigureMessage& message);
AFSKDataMessage data_message { false, 0 };
};
#endif/*__PROC_NRFRX_H__*/

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@ -78,6 +78,7 @@ public:
AFSKRxConfigure = 22,
StatusRefresh = 23,
SamplerateConfig = 24,
NRFRxConfigure = 26,
TXProgress = 30,
Retune = 31,
@ -722,6 +723,27 @@ public:
const bool trigger_word;
};
class NRFRxConfigureMessage : public Message {
public:
constexpr NRFRxConfigureMessage(
const uint32_t baudrate,
const uint32_t word_length,
const uint32_t trigger_value,
const bool trigger_word
) : Message { ID::NRFRxConfigure },
baudrate(baudrate),
word_length(word_length),
trigger_value(trigger_value),
trigger_word(trigger_word)
{
}
const uint32_t baudrate;
const uint32_t word_length;
const uint32_t trigger_value;
const bool trigger_word;
};
class PitchRSSIConfigureMessage : public Message {
public:
constexpr PitchRSSIConfigureMessage(

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@ -68,6 +68,7 @@ private:
constexpr image_tag_t image_tag_acars { 'P', 'A', 'C', 'A' };
constexpr image_tag_t image_tag_adsb_rx { 'P', 'A', 'D', 'R' };
constexpr image_tag_t image_tag_afsk_rx { 'P', 'A', 'F', 'R' };
constexpr image_tag_t image_tag_nrf_rx { 'P', 'N', 'R', 'R' };
constexpr image_tag_t image_tag_ais { 'P', 'A', 'I', 'S' };
constexpr image_tag_t image_tag_am_audio { 'P', 'A', 'M', 'A' };
constexpr image_tag_t image_tag_capture { 'P', 'C', 'A', 'P' };