Add external 2-Tone TX/RX Apps (#3128)

firmware/application/baseband_api.cpp

@@ -393,6 +393,11 @@ void set_moreserx_config(uint8_t mode) {
     send_message(&message);
 }
 
+void set_tonedetect_config(uint8_t squelch, uint32_t ctcss_freq_x10) {
+    const ToneDetectConfigureMessage message{squelch, ctcss_freq_x10};
+    send_message(&message);
+}
+
 void set_morsetx_config(uint8_t mode, uint32_t tone, float fm_delta) {
     const MorseTXConfigureMessage message{mode, tone, fm_delta};
     send_message(&message);

firmware/application/baseband_api.hpp

@@ -108,6 +108,7 @@ void set_siggen_config(const uint32_t bw, const uint32_t shape, const uint32_t d
 void set_spectrum_painter_config(const uint16_t width, const uint16_t height, bool update, int32_t bw);
 void set_subghzd_config(uint8_t modulation, uint32_t sampling_rate);
 void set_moreserx_config(uint8_t mode);
+void set_tonedetect_config(uint8_t squelch, uint32_t ctcss_freq_x10 = 0);
 void set_morsetx_config(uint8_t mode, uint32_t tone, float fm_delta);
 void set_morsetx_key(bool key_down);
 void set_wefax_config(uint8_t lpm, uint8_t ioc);

firmware/application/external/external.cmake

@@ -340,6 +340,14 @@ set(EXTCPPSRC
 	#p25_tx
 	external/p25_tx/main.cpp
 	external/p25_tx/ui_p25_tx.cpp
+
+	#two_tone_pager
+	external/two_tone_pager/main.cpp
+	external/two_tone_pager/ui_two_tone_pager.cpp
+
+	#two_tone_rx
+	external/two_tone_rx/main.cpp
+	external/two_tone_rx/ui_two_tone_rx.cpp
 )
 
 set(EXTAPPLIST
@@ -425,6 +433,8 @@ set(EXTAPPLIST
 	time_sink
 	kiss_tnc
 	p25_tx
+	two_tone_pager
+	two_tone_rx
 )
 
 # sdusb has type conflicts with PRALINE (HackRF Pro) - add only for non-PRALINE builds

firmware/application/external/external.ld

@@ -106,6 +106,8 @@ MEMORY
     ram_external_app_epirb_tx              (rwx) : org = 0xAE010000, len = 32k
     ram_external_app_fpv_detect            (rwx) : org = 0xAE020000, len = 32k
     ram_external_app_p25_tx                (rwx) : org = 0xAE030000, len = 32k
+    ram_external_app_two_tone_pager        (rwx) : org = 0xAE040000, len = 32k
+    ram_external_app_two_tone_rx           (rwx) : org = 0xAE050000, len = 32k
 }
 
 SECTIONS
@@ -607,4 +609,16 @@ SECTIONS
         KEEP(*(.external_app.app_p25_tx.application_information));
         *(*ui*external_app*p25_tx*);
     } > ram_external_app_p25_tx
+
+    .external_app_two_tone_pager : ALIGN(4) SUBALIGN(4)
+    {
+        KEEP(*(.external_app.app_two_tone_pager.application_information));
+        *(*ui*external_app*two_tone_pager*);
+    } > ram_external_app_two_tone_pager
+
+    .external_app_two_tone_rx : ALIGN(4) SUBALIGN(4)
+    {
+        KEEP(*(.external_app.app_two_tone_rx.application_information));
+        *(*ui*external_app*two_tone_rx*);
+    } > ram_external_app_two_tone_rx
 }

firmware/application/external/two_tone_pager/main.cpp

@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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.hpp"
+#include "ui_two_tone_pager.hpp"
+#include "ui_navigation.hpp"
+#include "external_app.hpp"
+
+namespace ui::external_app::two_tone_pager {
+void initialize_app(ui::NavigationView& nav) {
+    nav.push<TwoTonePagerView>();
+}
+}  // namespace ui::external_app::two_tone_pager
+
+extern "C" {
+
+__attribute__((section(".external_app.app_two_tone_pager.application_information"), used)) application_information_t _application_information_two_tone_pager = {
+    /*.memory_location = */ (uint8_t*)0x00000000,
+    /*.externalAppEntry = */ ui::external_app::two_tone_pager::initialize_app,
+    /*.header_version = */ CURRENT_HEADER_VERSION,
+    /*.app_version = */ VERSION_MD5,
+
+    /*.app_name = */ "2-Tone TX",
+    /*.bitmap_data = */ {
+        // 16×16 pager icon — two-tone radio / pager device
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0xFC,
+        0x3F,
+        0xFE,
+        0x7F,
+        0x02,
+        0x40,
+        0xBA,
+        0x45,
+        0x02,
+        0x40,
+        0xFE,
+        0x7F,
+        0xFE,
+        0x7F,
+        0x92,
+        0x7C,
+        0x92,
+        0x7C,
+        0xFC,
+        0x3F,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+    },
+    /*.icon_color = */ ui::Color::orange().v,
+    /*.menu_location = */ app_location_t::TX,
+    /*.desired_menu_position = */ -1,
+
+    // Uses the proc_tones baseband processor (same as Morse TX)
+    /*.m4_app_tag = portapack::spi_flash::image_tag_tones */ {'P', 'T', 'O', 'N'},
+    /*.m4_app_offset = */ 0x00000000,  // filled at compile time
+};
+
+}  // extern "C"

firmware/application/external/two_tone_pager/ui_two_tone_pager.cpp

@@ -0,0 +1,616 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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_two_tone_pager.hpp"
+
+#include "portapack.hpp"
+#include "baseband_api.hpp"
+#include "portapack_shared_memory.hpp"
+#include "string_format.hpp"
+#include "theme.hpp"
+
+#include <algorithm>
+#include <cstring>
+
+using namespace portapack;
+
+namespace ui::external_app::two_tone_pager {
+
+// ---------------------------------------------------------------------------
+// Tone tables — store only freq×10 values; names are generated at runtime
+// to keep static data small and avoid const-char-pointer patching issues.
+// ---------------------------------------------------------------------------
+
+static const uint32_t MOTO_FREQS[45] = {
+    2885,
+    3047,
+    3217,
+    3396,
+    3586,
+    3786,
+    3998,
+    4221,
+    4457,
+    4705,
+    4968,
+    5246,
+    5539,
+    5848,
+    6174,
+    6519,
+    6883,
+    7268,
+    7674,
+    8102,
+    8555,
+    9032,
+    9537,
+    10073,
+    10642,
+    11225,
+    11247,
+    11534,
+    11852,
+    11885,
+    12178,
+    12514,
+    12555,
+    12858,
+    13258,
+    13576,
+    13950,
+    13996,
+    14768,
+    15579,
+    16430,
+    17325,
+    18262,
+    19245,
+    20275,
+};
+
+// Index 0 = None (0), indices 1-50 = standard CTCSS tones
+static const uint32_t CTCSS_FREQS[51] = {
+    0,
+    670,
+    719,
+    744,
+    770,
+    797,
+    825,
+    854,
+    885,
+    915,
+    948,
+    974,
+    1000,
+    1035,
+    1072,
+    1109,
+    1148,
+    1188,
+    1230,
+    1273,
+    1318,
+    1365,
+    1413,
+    1462,
+    1500,
+    1514,
+    1567,
+    1598,
+    1622,
+    1655,
+    1679,
+    1713,
+    1738,
+    1773,
+    1799,
+    1835,
+    1862,
+    1899,
+    1928,
+    1966,
+    1995,
+    2035,
+    2065,
+    2107,
+    2181,
+    2257,
+    2291,
+    2336,
+    2418,
+    2503,
+    2541,
+};
+
+// Generate a display name from a freq×10 value ("288.5Hz", "None" for 0)
+static std::string freq_name(uint32_t freq_x10) {
+    if (freq_x10 == 0) return "None";
+    return to_string_dec_uint(freq_x10 / 10) + "." +
+           to_string_dec_uint(freq_x10 % 10) + "Hz";
+}
+
+// Common timing profiles used in the field
+struct TimingPreset {
+    uint32_t dur_a;  // ms
+    uint32_t dur_b;  // ms
+    uint32_t gap;    // ms
+};
+
+static const TimingPreset TIMING_PRESETS[4] = {
+    {1000, 3000, 0},  // Moto Std
+    {700, 1000, 0},   // Short Alert
+    {2000, 1000, 0},  // Fire Std
+    {3000, 3000, 0},  // Long Alert
+};
+
+// ---------------------------------------------------------------------------
+// Helpers
+// ---------------------------------------------------------------------------
+
+// Parse one unsigned decimal integer from *p, advancing p past the digits and
+// an optional trailing comma.
+static uint32_t parse_uint_field(const char*& p) {
+    uint32_t v = 0;
+    while (*p >= '0' && *p <= '9')
+        v = v * 10 + (*p++ - '0');
+    if (*p == ',')
+        ++p;
+    return v;
+}
+
+// Phase-delta for the 32-bit sine-table accumulator used by proc_tones.
+// delta = freq_hz * 2^32 / sample_rate
+// Using freq_x10 to avoid floating-point: delta = (freq_x10 * 2^32) / (sample_rate * 10)
+uint32_t TwoTonePagerView::tone_delta(uint32_t freq_x10) const {
+    if (freq_x10 == 0) return 0;
+    return static_cast<uint32_t>(
+        (static_cast<uint64_t>(freq_x10) << 32) /
+        (static_cast<uint64_t>(SAMPLE_RATE) * 10ULL));
+}
+
+uint32_t TwoTonePagerView::ms_to_samples(uint32_t ms) const {
+    return static_cast<uint32_t>(
+        (static_cast<uint64_t>(ms) * SAMPLE_RATE) / 1000ULL);
+}
+
+// ---------------------------------------------------------------------------
+// Preset encode / decode
+// ---------------------------------------------------------------------------
+
+std::string TwoTonePagerView::encode_preset() const {
+    return to_string_dec_uint(ctcss_idx) + "," +
+           to_string_dec_uint(tone_a_idx) + "," +
+           to_string_dec_uint(tone_b_idx) + "," +
+           to_string_dec_uint(dur_a) + "," +
+           to_string_dec_uint(dur_b) + "," +
+           to_string_dec_uint(gap_ms) + "," +
+           to_string_dec_uint(custom_freq_a_hz) + "," +
+           to_string_dec_uint(custom_freq_b_hz);
+}
+
+void TwoTonePagerView::decode_preset(const std::string& s) {
+    const char* p = s.c_str();
+    uint32_t ci = parse_uint_field(p);
+    uint32_t ai = parse_uint_field(p);
+    uint32_t bi = parse_uint_field(p);
+    uint32_t da = parse_uint_field(p);
+    uint32_t db = parse_uint_field(p);
+    uint32_t gp = parse_uint_field(p);
+
+    uint32_t cfa = (*p != '\0') ? parse_uint_field(p) : 405;
+    uint32_t cfb = (*p != '\0') ? parse_uint_field(p) : 814;
+
+    ctcss_idx = std::min(ci, static_cast<uint32_t>(CTCSS_COUNT - 1));
+    tone_a_idx = std::min(ai, CUSTOM_TONE_IDX);
+    tone_b_idx = std::min(bi, CUSTOM_TONE_IDX);
+    dur_a = std::max(uint32_t{100}, std::min(da, uint32_t{9900}));
+    dur_b = std::max(uint32_t{100}, std::min(db, uint32_t{9900}));
+    gap_ms = std::min(gp, uint32_t{9900});
+    custom_freq_a_hz = std::max(uint32_t{100}, std::min(cfa, uint32_t{9999}));
+    custom_freq_b_hz = std::max(uint32_t{100}, std::min(cfb, uint32_t{9999}));
+}
+
+std::string& TwoTonePagerView::slot_ref(uint32_t slot) {
+    switch (slot) {
+        case 2:
+            return preset_2;
+        case 3:
+            return preset_3;
+        case 4:
+            return preset_4;
+        case 5:
+            return preset_5;
+        default:
+            return preset_1;
+    }
+}
+
+std::string& TwoTonePagerView::slot_name_ref(uint32_t slot) {
+    switch (slot) {
+        case 2:
+            return preset_name_2;
+        case 3:
+            return preset_name_3;
+        case 4:
+            return preset_name_4;
+        case 5:
+            return preset_name_5;
+        default:
+            return preset_name_1;
+    }
+}
+
+void TwoTonePagerView::update_slot_name_display() {
+    const auto& name = slot_name_ref(preset_slot);
+    std::string display = name.empty() ? "(none)" : name;
+    if (display.size() > 8) display = display.substr(0, 8);
+    text_slot_name.set(display);
+}
+
+void TwoTonePagerView::save_preset(uint32_t slot) {
+    slot_ref(slot) = encode_preset();
+    text_status.set("Saved to slot " + to_string_dec_uint(slot));
+}
+
+void TwoTonePagerView::load_preset(uint32_t slot) {
+    decode_preset(slot_ref(slot));
+
+    // Update all UI fields without firing their on_change callbacks
+    options_ctcss.set_selected_index(ctcss_idx, false);
+    options_tone_a.set_selected_index(tone_a_idx, false);
+    options_tone_b.set_selected_index(tone_b_idx, false);
+    field_dur_a.set_value(static_cast<int32_t>(dur_a), false);
+    field_dur_b.set_value(static_cast<int32_t>(dur_b), false);
+    field_gap.set_value(static_cast<int32_t>(gap_ms), false);
+    symfield_custom_a.set_value(custom_freq_a_hz);
+    symfield_custom_b.set_value(custom_freq_b_hz);
+    options_timing.set_selected_index(detect_timing_preset(), false);
+
+    update_tx_time();
+    update_slot_name_display();
+    text_status.set("Loaded slot " + to_string_dec_uint(slot));
+}
+
+// ---------------------------------------------------------------------------
+// Timing presets
+// ---------------------------------------------------------------------------
+
+size_t TwoTonePagerView::detect_timing_preset() const {
+    for (size_t i = 0; i < 4; i++) {
+        if (TIMING_PRESETS[i].dur_a == dur_a &&
+            TIMING_PRESETS[i].dur_b == dur_b &&
+            TIMING_PRESETS[i].gap == gap_ms)
+            return i;
+    }
+    return 4;  // "Custom"
+}
+
+void TwoTonePagerView::apply_timing_preset(size_t idx) {
+    if (idx >= 4) return;  // "Custom" — do not override current values
+    dur_a = TIMING_PRESETS[idx].dur_a;
+    dur_b = TIMING_PRESETS[idx].dur_b;
+    gap_ms = TIMING_PRESETS[idx].gap;
+    field_dur_a.set_value(static_cast<int32_t>(dur_a), false);
+    field_dur_b.set_value(static_cast<int32_t>(dur_b), false);
+    field_gap.set_value(static_cast<int32_t>(gap_ms), false);
+    update_tx_time();
+}
+
+// ---------------------------------------------------------------------------
+// UI helpers
+// ---------------------------------------------------------------------------
+
+void TwoTonePagerView::update_tx_time() {
+    uint32_t total_ms = dur_a + gap_ms + dur_b;
+    std::string name_a = (tone_a_idx == CUSTOM_TONE_IDX)
+                             ? to_string_dec_uint(custom_freq_a_hz) + "Hz"
+                             : freq_name(MOTO_FREQS[tone_a_idx]);
+    std::string name_b = (tone_b_idx == CUSTOM_TONE_IDX)
+                             ? to_string_dec_uint(custom_freq_b_hz) + "Hz"
+                             : freq_name(MOTO_FREQS[tone_b_idx]);
+    text_time.set("TX time: " +
+                  to_string_dec_uint(total_ms / 1000) + "." +
+                  to_string_dec_uint((total_ms / 100) % 10) + "s" +
+                  "  A:" + name_a + " B:" + name_b);
+}
+
+// ---------------------------------------------------------------------------
+// Transmission
+// ---------------------------------------------------------------------------
+
+bool TwoTonePagerView::start_tx() {
+    auto& td = shared_memory.bb_data.tones_data;
+
+    const uint32_t freq_a_x10 = (tone_a_idx == CUSTOM_TONE_IDX)
+                                    ? custom_freq_a_hz * 10
+                                    : MOTO_FREQS[tone_a_idx];
+    const uint32_t freq_b_x10 = (tone_b_idx == CUSTOM_TONE_IDX)
+                                    ? custom_freq_b_hz * 10
+                                    : MOTO_FREQS[tone_b_idx];
+    const uint32_t delta_a = tone_delta(freq_a_x10);
+    const uint32_t delta_b = tone_delta(freq_b_x10);
+    const uint32_t delta_c = tone_delta(CTCSS_FREQS[ctcss_idx]);
+    const uint32_t samp_a = ms_to_samples(dur_a);
+    const uint32_t samp_b = ms_to_samples(dur_b);
+    const uint32_t samp_g = ms_to_samples(gap_ms);
+    const bool with_ctcss = (ctcss_idx > 0);
+
+    // Clear tone defs we'll use
+    memset(&td, 0, sizeof(td));
+
+    uint8_t tone_count;
+
+    if (!with_ctcss) {
+        // Single-tone sequential mode
+        // tone_defs[0] = Tone A,  tone_defs[1] = Tone B
+        td.tone_defs[0].delta = delta_a;
+        td.tone_defs[0].duration = samp_a;
+        td.tone_defs[1].delta = delta_b;
+        td.tone_defs[1].duration = samp_b;
+
+        if (gap_ms > 0) {
+            td.silence = samp_g;
+            td.message[0] = 0;    // Tone A
+            td.message[1] = 255;  // Silence (any index ≥ 32 triggers silence)
+            td.message[2] = 1;    // Tone B
+            tone_count = 3;
+        } else {
+            td.message[0] = 0;  // Tone A
+            td.message[1] = 1;  // Tone B
+            tone_count = 2;
+        }
+    } else {
+        // Dual-tone mode: CTCSS mixed simultaneously with pager tones.
+        //
+        // proc_tones dual-tone indexing for digit n:
+        //   main delta = tone_deltas[n * 2]   = tone_defs[n*2].delta
+        //   sub  delta = tone_deltas[n*2 + 1] = tone_defs[n*2+1].delta
+        //   duration   = tone_durations[n]    = tone_defs[n].duration
+        //
+        // digit 0 → Tone A (main) + CTCSS (sub),  duration from tone_defs[0]
+        // digit 1 → Tone B (main) + CTCSS (sub),  duration from tone_defs[1]
+        td.tone_defs[0].delta = delta_a;  // digit 0 main
+        td.tone_defs[0].duration = samp_a;
+        td.tone_defs[1].delta = delta_c;  // digit 0 sub (CTCSS); also digit 1 duration source
+        td.tone_defs[1].duration = samp_b;
+        td.tone_defs[2].delta = delta_b;  // digit 1 main (Tone B)
+        td.tone_defs[2].duration = 0;     // duration for digit 1 comes from tone_defs[1]
+        td.tone_defs[3].delta = delta_c;  // digit 1 sub (CTCSS)
+        td.tone_defs[3].duration = 0;
+
+        if (gap_ms > 0) {
+            td.silence = samp_g;
+            td.message[0] = 0;
+            td.message[1] = 255;
+            td.message[2] = 1;
+            tone_count = 3;
+        } else {
+            td.message[0] = 0;
+            td.message[1] = 1;
+            tone_count = 2;
+        }
+    }
+
+    progressbar.set_max(tone_count);
+    progressbar.set_value(0);
+
+    transmitter_model.set_baseband_bandwidth(1'750'000);
+    transmitter_model.enable();
+
+    baseband::set_tones_config(
+        transmitter_model.channel_bandwidth(),
+        0,  // no pre-silence
+        tone_count,
+        with_ctcss,  // dual_tone flag
+        false);      // no audio monitor output
+
+    return true;
+}
+
+void TwoTonePagerView::stop_tx() {
+    transmitter_model.disable();
+    baseband::kill_tone();
+    tx_view.set_transmitting(false);
+    text_status.set("Stopped.");
+}
+
+void TwoTonePagerView::on_tx_progress(uint32_t progress, bool done) {
+    if (done) {
+        transmitter_model.disable();
+        progressbar.set_value(0);
+        tx_view.set_transmitting(false);
+        text_status.set("Done.");
+    } else {
+        progressbar.set_value(progress);
+    }
+}
+
+// ---------------------------------------------------------------------------
+// View lifecycle
+// ---------------------------------------------------------------------------
+
+void TwoTonePagerView::focus() {
+    options_tone_a.focus();
+}
+
+TwoTonePagerView::~TwoTonePagerView() {
+    transmitter_model.disable();
+    baseband::shutdown();
+}
+
+TwoTonePagerView::TwoTonePagerView(NavigationView& nav)
+    : nav_(nav) {
+    baseband::run_prepared_image(portapack::memory::map::m4_code.base());
+
+    // Clamp restored settings to valid ranges before touching UI
+    ctcss_idx = std::min(ctcss_idx, static_cast<uint32_t>(CTCSS_COUNT - 1));
+    tone_a_idx = std::min(tone_a_idx, CUSTOM_TONE_IDX);
+    tone_b_idx = std::min(tone_b_idx, CUSTOM_TONE_IDX);
+    dur_a = std::max(uint32_t{100}, std::min(dur_a, uint32_t{9900}));
+    dur_b = std::max(uint32_t{100}, std::min(dur_b, uint32_t{9900}));
+    gap_ms = std::min(gap_ms, uint32_t{9900});
+    preset_slot = std::max(uint32_t{1}, std::min(preset_slot, uint32_t{5}));
+    custom_freq_a_hz = std::max(uint32_t{100}, std::min(custom_freq_a_hz, uint32_t{9999}));
+    custom_freq_b_hz = std::max(uint32_t{100}, std::min(custom_freq_b_hz, uint32_t{9999}));
+
+    // Build CTCSS options list
+    {
+        std::vector<std::pair<std::string, int32_t>> opts;
+        opts.reserve(CTCSS_COUNT);
+        for (size_t i = 0; i < CTCSS_COUNT; i++)
+            opts.push_back({freq_name(CTCSS_FREQS[i]), static_cast<int32_t>(i)});
+        options_ctcss.set_options(std::move(opts));
+    }
+
+    // Build Motorola tone options (same pool for both A and B); "Custom" appended
+    {
+        std::vector<std::pair<std::string, int32_t>> opts;
+        opts.reserve(MOTO_TONE_COUNT + 1);
+        for (size_t i = 0; i < MOTO_TONE_COUNT; i++)
+            opts.push_back({freq_name(MOTO_FREQS[i]), static_cast<int32_t>(i)});
+        opts.push_back({"Custom", static_cast<int32_t>(CUSTOM_TONE_IDX)});
+        options_tone_a.set_options(opts);
+        options_tone_b.set_options(std::move(opts));
+    }
+
+    add_children({&labels,
+                  &options_ctcss,
+                  &options_tone_a,
+                  &options_tone_b,
+                  &symfield_custom_a,
+                  &symfield_custom_b,
+                  &field_dur_a,
+                  &field_dur_b,
+                  &field_gap,
+                  &options_timing,
+                  &field_slot,
+                  &button_save,
+                  &button_load,
+                  &text_slot_name,
+                  &text_time,
+                  &text_status,
+                  &progressbar,
+                  &tx_view});
+
+    // Restore saved indices into the options / number fields (no callbacks)
+    options_ctcss.set_selected_index(ctcss_idx, false);
+    options_tone_a.set_selected_index(tone_a_idx, false);
+    options_tone_b.set_selected_index(tone_b_idx, false);
+    symfield_custom_a.set_value(custom_freq_a_hz);
+    symfield_custom_b.set_value(custom_freq_b_hz);
+    field_dur_a.set_value(static_cast<int32_t>(dur_a), false);
+    field_dur_b.set_value(static_cast<int32_t>(dur_b), false);
+    field_gap.set_value(static_cast<int32_t>(gap_ms), false);
+    options_timing.set_selected_index(detect_timing_preset(), false);
+    field_slot.set_value(static_cast<int32_t>(preset_slot), false);
+
+    update_tx_time();
+    update_slot_name_display();
+
+    // --- Callbacks ---
+
+    options_ctcss.on_change = [this](size_t i, int32_t) {
+        ctcss_idx = static_cast<uint32_t>(i);
+    };
+
+    options_tone_a.on_change = [this](size_t i, int32_t) {
+        tone_a_idx = static_cast<uint32_t>(i);
+        update_tx_time();
+    };
+
+    options_tone_b.on_change = [this](size_t i, int32_t) {
+        tone_b_idx = static_cast<uint32_t>(i);
+        update_tx_time();
+    };
+
+    symfield_custom_a.on_change = [this](SymField&) {
+        uint32_t v = static_cast<uint32_t>(symfield_custom_a.to_integer());
+        custom_freq_a_hz = std::max(uint32_t{100}, std::min(v, uint32_t{9999}));
+        update_tx_time();
+    };
+
+    symfield_custom_b.on_change = [this](SymField&) {
+        uint32_t v = static_cast<uint32_t>(symfield_custom_b.to_integer());
+        custom_freq_b_hz = std::max(uint32_t{100}, std::min(v, uint32_t{9999}));
+        update_tx_time();
+    };
+
+    field_dur_a.on_change = [this](int32_t v) {
+        dur_a = static_cast<uint32_t>(v);
+        options_timing.set_selected_index(detect_timing_preset(), false);
+        update_tx_time();
+    };
+
+    field_dur_b.on_change = [this](int32_t v) {
+        dur_b = static_cast<uint32_t>(v);
+        options_timing.set_selected_index(detect_timing_preset(), false);
+        update_tx_time();
+    };
+
+    field_gap.on_change = [this](int32_t v) {
+        gap_ms = static_cast<uint32_t>(v);
+        options_timing.set_selected_index(detect_timing_preset(), false);
+        update_tx_time();
+    };
+
+    options_timing.on_change = [this](size_t i, int32_t) {
+        apply_timing_preset(i);
+    };
+
+    field_slot.on_change = [this](int32_t v) {
+        preset_slot = static_cast<uint32_t>(v);
+        update_slot_name_display();
+    };
+
+    button_save.on_select = [this](Button&) {
+        text_prompt(nav_, slot_name_ref(preset_slot), 12, ENTER_KEYBOARD_MODE_ALPHA,
+                    [this](std::string&) {
+                        save_preset(preset_slot);
+                        update_slot_name_display();
+                    });
+    };
+
+    button_load.on_select = [this](Button&) {
+        load_preset(preset_slot);
+    };
+
+    tx_view.on_edit_frequency = [this, &nav]() {
+        auto new_view = nav.push<FrequencyKeypadView>(transmitter_model.target_frequency());
+        new_view->on_changed = [this](rf::Frequency f) {
+            transmitter_model.set_target_frequency(f);
+        };
+    };
+
+    tx_view.on_start = [this]() {
+        if (start_tx()) {
+            tx_view.set_transmitting(true);
+            text_status.set("Transmitting...");
+        }
+    };
+
+    tx_view.on_stop = [this]() {
+        stop_tx();
+    };
+}
+
+}  // namespace ui::external_app::two_tone_pager

firmware/application/external/two_tone_pager/ui_two_tone_pager.hpp

@@ -0,0 +1,250 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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_TWO_TONE_PAGER_H__
+#define __UI_TWO_TONE_PAGER_H__
+
+#include "ui.hpp"
+#include "ui_widget.hpp"
+#include "ui_navigation.hpp"
+#include "ui_transmitter.hpp"
+#include "ui_textentry.hpp"
+#include "app_settings.hpp"
+#include "radio_state.hpp"
+#include "portapack.hpp"
+#include "message.hpp"
+#include "string_format.hpp"
+
+namespace ui::external_app::two_tone_pager {
+
+class TwoTonePagerView : public View {
+   public:
+    TwoTonePagerView(NavigationView& nav);
+    ~TwoTonePagerView();
+
+    TwoTonePagerView(const TwoTonePagerView&) = delete;
+    TwoTonePagerView(TwoTonePagerView&&) = delete;
+    TwoTonePagerView& operator=(const TwoTonePagerView&) = delete;
+    TwoTonePagerView& operator=(TwoTonePagerView&&) = delete;
+
+    void focus() override;
+    std::string title() const override { return "2-Tone TX"; };
+
+   private:
+    NavigationView& nav_;
+
+    static constexpr uint32_t SAMPLE_RATE = 1536000;
+    static constexpr size_t MOTO_TONE_COUNT = 45;
+    static constexpr size_t CTCSS_COUNT = 51;
+    static constexpr uint32_t CUSTOM_TONE_IDX = MOTO_TONE_COUNT;  // sentinel: one past the table, use custom Hz field
+
+    TxRadioState radio_state_{
+        154280000ULL,  // 154.280 MHz — common VHF paging frequency
+        1750000,
+        SAMPLE_RATE};
+
+    // Persisted settings
+    uint32_t ctcss_idx{0};
+    uint32_t tone_a_idx{8};   // 405.3 Hz
+    uint32_t tone_b_idx{24};  // 813.9 Hz
+    uint32_t dur_a{1000};
+    uint32_t dur_b{3000};
+    uint32_t gap_ms{0};
+    uint32_t preset_slot{1};
+    uint32_t custom_freq_a_hz{405};  // used when tone_a_idx == CUSTOM_TONE_IDX
+    uint32_t custom_freq_b_hz{814};
+
+    // Five preset slots — encoded tone/timing data and a user-chosen display name
+    std::string preset_1{"0,8,24,1000,3000,0"};
+    std::string preset_2{"0,8,24,1000,3000,0"};
+    std::string preset_3{"0,8,24,1000,3000,0"};
+    std::string preset_4{"0,8,24,1000,3000,0"};
+    std::string preset_5{"0,8,24,1000,3000,0"};
+    std::string preset_name_1{""};
+    std::string preset_name_2{""};
+    std::string preset_name_3{""};
+    std::string preset_name_4{""};
+    std::string preset_name_5{""};
+
+    app_settings::SettingsManager settings_{
+        "tx_twotone",
+        app_settings::Mode::TX,
+        {
+            {"ctcss"sv, &ctcss_idx},
+            {"tone_a"sv, &tone_a_idx},
+            {"tone_b"sv, &tone_b_idx},
+            {"dur_a"sv, &dur_a},
+            {"dur_b"sv, &dur_b},
+            {"gap"sv, &gap_ms},
+            {"slot"sv, &preset_slot},
+            {"custom_a"sv, &custom_freq_a_hz},
+            {"custom_b"sv, &custom_freq_b_hz},
+            {"preset1"sv, &preset_1},
+            {"preset2"sv, &preset_2},
+            {"preset3"sv, &preset_3},
+            {"preset4"sv, &preset_4},
+            {"preset5"sv, &preset_5},
+            {"pname1"sv, &preset_name_1},
+            {"pname2"sv, &preset_name_2},
+            {"pname3"sv, &preset_name_3},
+            {"pname4"sv, &preset_name_4},
+            {"pname5"sv, &preset_name_5},
+        }};
+
+    bool start_tx();
+    void stop_tx();
+    void on_tx_progress(uint32_t progress, bool done);
+    void apply_timing_preset(size_t idx);
+    void save_preset(uint32_t slot);
+    void load_preset(uint32_t slot);
+    std::string encode_preset() const;
+    void decode_preset(const std::string& s);
+    std::string& slot_ref(uint32_t slot);
+    std::string& slot_name_ref(uint32_t slot);
+    uint32_t tone_delta(uint32_t freq_x10) const;
+    uint32_t ms_to_samples(uint32_t ms) const;
+    size_t detect_timing_preset() const;
+    void update_tx_time();
+    void update_slot_name_display();
+
+    // --- Widgets ---
+
+    Labels labels{
+        {{0 * 8, 1 * 16}, "CTCSS:", Theme::getInstance()->fg_light->foreground},
+        {{0 * 8, 2 * 16}, "A:", Theme::getInstance()->fg_light->foreground},
+        {{13 * 8, 2 * 16}, "B:", Theme::getInstance()->fg_light->foreground},
+        {{0 * 8, 3 * 16}, "ADur:", Theme::getInstance()->fg_light->foreground},
+        {{9 * 8, 3 * 16}, "ms", Theme::getInstance()->fg_light->foreground},
+        {{12 * 8, 3 * 16}, "BDur:", Theme::getInstance()->fg_light->foreground},
+        {{21 * 8, 3 * 16}, "ms", Theme::getInstance()->fg_light->foreground},
+        {{0 * 8, 4 * 16}, "Gap: ", Theme::getInstance()->fg_light->foreground},
+        {{9 * 8, 4 * 16}, "ms", Theme::getInstance()->fg_light->foreground},
+        {{0 * 8, 5 * 16}, "Timing:", Theme::getInstance()->fg_light->foreground},
+        {{0 * 8, 6 * 16}, "Slot: ", Theme::getInstance()->fg_light->foreground},
+        {{0 * 8, 9 * 16}, "AHz:", Theme::getInstance()->fg_light->foreground},
+        {{8 * 8, 9 * 16}, "Hz", Theme::getInstance()->fg_light->foreground},
+        {{13 * 8, 9 * 16}, "BHz:", Theme::getInstance()->fg_light->foreground},
+        {{21 * 8, 9 * 16}, "Hz", Theme::getInstance()->fg_light->foreground},
+    };
+
+    OptionsField options_ctcss{
+        {7 * 8, 1 * 16},
+        9,
+        {}};
+
+    OptionsField options_tone_a{
+        {3 * 8, 2 * 16},
+        9,
+        {}};
+
+    OptionsField options_tone_b{
+        {16 * 8, 2 * 16},
+        9,
+        {}};
+
+    NumberField field_dur_a{
+        {5 * 8, 3 * 16},
+        4,
+        {100, 9900},
+        100,
+        ' '};
+
+    NumberField field_dur_b{
+        {17 * 8, 3 * 16},
+        4,
+        {100, 9900},
+        100,
+        ' '};
+
+    // Digit-by-digit entry for custom tone frequency (integer Hz, 4 slots, 0100–9999)
+    SymField symfield_custom_a{
+        {4 * 8, 9 * 16},
+        4,
+        SymField::Type::Dec};
+
+    SymField symfield_custom_b{
+        {17 * 8, 9 * 16},
+        4,
+        SymField::Type::Dec};
+
+    NumberField field_gap{
+        {5 * 8, 4 * 16},
+        4,
+        {0, 9900},
+        50,
+        ' '};
+
+    OptionsField options_timing{
+        {8 * 8, 5 * 16},
+        12,
+        {{"Moto Std", 0},
+         {"Short Alert", 1},
+         {"Fire Std", 2},
+         {"Long Alert", 3},
+         {"Custom", 4}}};
+
+    NumberField field_slot{
+        {7 * 8, 6 * 16},
+        1,
+        {1, 5},
+        1,
+        ' '};
+
+    Button button_save{
+        {9 * 8, 6 * 16, 6 * 8, 20},
+        "Save"};
+
+    Button button_load{
+        {16 * 8, 6 * 16, 6 * 8, 20},
+        "Load"};
+
+    // Shows the name of the currently selected preset slot (up to 8 visible chars)
+    Text text_slot_name{
+        {22 * 8, 6 * 16, 8 * 8, 16},
+        ""};
+
+    Text text_time{
+        {0, 7 * 16, 30 * 8, 16},
+        ""};
+
+    Text text_status{
+        {0, 8 * 16, 30 * 8, 16},
+        ""};
+
+    ProgressBar progressbar{
+        {2 * 8, 14 * 16, UI_POS_WIDTH_REMAINING(4), 16}};
+
+    TransmitterView tx_view{
+        (int16_t)UI_POS_Y_BOTTOM(4),
+        10000,
+        9};
+
+    MessageHandlerRegistration message_handler_tx_progress{
+        Message::ID::TXProgress,
+        [this](const Message* const p) {
+            const auto msg = *reinterpret_cast<const TXProgressMessage*>(p);
+            this->on_tx_progress(msg.progress, msg.done);
+        }};
+};
+
+}  // namespace ui::external_app::two_tone_pager
+
+#endif /* __UI_TWO_TONE_PAGER_H__ */

firmware/application/external/two_tone_rx/main.cpp

@@ -0,0 +1,86 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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.hpp"
+#include "ui_two_tone_rx.hpp"
+#include "ui_navigation.hpp"
+#include "external_app.hpp"
+
+namespace ui::external_app::two_tone_rx {
+void initialize_app(ui::NavigationView& nav) {
+    nav.push<TwoToneRxView>();
+}
+}  // namespace ui::external_app::two_tone_rx
+
+extern "C" {
+
+__attribute__((section(".external_app.app_two_tone_rx.application_information"), used)) application_information_t _application_information_two_tone_rx = {
+    /*.memory_location = */ (uint8_t*)0x00000000,
+    /*.externalAppEntry = */ ui::external_app::two_tone_rx::initialize_app,
+    /*.header_version = */ CURRENT_HEADER_VERSION,
+    /*.app_version = */ VERSION_MD5,
+
+    /*.app_name = */ "2-Tone RX",
+    /*.bitmap_data = */ {
+        // 16×16 icon — pager device with receive arrow
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0xFC,
+        0x3F,
+        0xFE,
+        0x7F,
+        0x02,
+        0x40,
+        0xBA,
+        0x5D,
+        0x02,
+        0x40,
+        0xFE,
+        0x7F,
+        0xFE,
+        0x7F,
+        0x12,
+        0x48,
+        0x12,
+        0x48,
+        0xFC,
+        0x3F,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+        0x00,
+    },
+    /*.icon_color = */ ui::Color::yellow().v,
+    /*.menu_location = */ app_location_t::RX,
+    /*.desired_menu_position = */ -1,
+
+    // Uses the proc_tonedetect baseband processor
+    /*.m4_app_tag = portapack::spi_flash::image_tag_tonedetect */ {'P', 'T', 'N', 'E'},
+    /*.m4_app_offset = */ 0x00000000,  // filled at compile time
+};
+
+}  // extern "C"

firmware/application/external/two_tone_rx/ui_two_tone_rx.cpp

@@ -0,0 +1,599 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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_two_tone_rx.hpp"
+#include "audio.hpp"
+#include "baseband_api.hpp"
+#include "portapack.hpp"
+#include "string_format.hpp"
+
+using namespace portapack;
+
+namespace ui::external_app::two_tone_rx {
+
+static constexpr uint32_t DETECT_WINDOW_MS = 40;
+static constexpr Coord screen_width_px = 240;
+static constexpr Coord screen_height_px = 320;
+static constexpr Coord tone_log_top = 4 * 16;
+static constexpr Coord waterfall_top = 13 * 16;
+static constexpr Coord waterfall_height = 6 * 16;
+static constexpr Rect tone_log_rect{0, tone_log_top, 30 * 8, waterfall_top - tone_log_top};
+
+// ---------------------------------------------------------------------------
+// Tone tables
+// ---------------------------------------------------------------------------
+
+static const uint32_t MOTO_FREQS[45] = {
+    2885,
+    3047,
+    3217,
+    3396,
+    3586,
+    3786,
+    3998,
+    4221,
+    4457,
+    4705,
+    4968,
+    5246,
+    5539,
+    5848,
+    6174,
+    6519,
+    6883,
+    7268,
+    7674,
+    8102,
+    8555,
+    9032,
+    9537,
+    10073,
+    10642,
+    11225,
+    11247,
+    11534,
+    11852,
+    11885,
+    12178,
+    12514,
+    12555,
+    12858,
+    13258,
+    13576,
+    13950,
+    13996,
+    14768,
+    15579,
+    16430,
+    17325,
+    18262,
+    19245,
+    20275,
+};
+
+// Index 0 = None (0), indices 1–50 = standard CTCSS tones (freq × 10)
+static const uint32_t CTCSS_FREQS[51] = {
+    0,
+    670,
+    719,
+    744,
+    770,
+    797,
+    825,
+    854,
+    885,
+    915,
+    948,
+    974,
+    1000,
+    1035,
+    1072,
+    1109,
+    1148,
+    1188,
+    1230,
+    1273,
+    1318,
+    1365,
+    1413,
+    1462,
+    1500,
+    1514,
+    1567,
+    1598,
+    1622,
+    1655,
+    1679,
+    1713,
+    1738,
+    1773,
+    1799,
+    1835,
+    1862,
+    1899,
+    1928,
+    1966,
+    1995,
+    2035,
+    2065,
+    2107,
+    2181,
+    2257,
+    2291,
+    2336,
+    2418,
+    2503,
+    2541,
+};
+
+static std::string ctcss_name(uint32_t freq_x10) {
+    if (freq_x10 == 0) return "None";
+    return to_string_dec_uint(freq_x10 / 10) + "." +
+           to_string_dec_uint(freq_x10 % 10) + "Hz";
+}
+
+// ---------------------------------------------------------------------------
+// MOTO table helpers
+// ---------------------------------------------------------------------------
+
+static constexpr uint32_t MOTO_NONE = 255;
+static constexpr uint32_t MOTO_TRANSITION_SNAP_HZ = 30;   // stricter live transition tolerance
+static constexpr uint32_t MOTO_FINAL_MATCH_HZ = 60;       // looser phase-end/logging tolerance
+static constexpr uint32_t MOTO_TRANSITION_DELTA_HZ = 25;  // raw shift needed to confirm close-in A→B handoff
+
+static uint32_t abs_diff_u32(uint32_t a, uint32_t b) {
+    return (a > b) ? (a - b) : (b - a);
+}
+
+// Return the nearest MOTO table index within match_hz, or MOTO_NONE.
+static uint32_t moto_index(uint32_t freq_hz, uint32_t match_hz = MOTO_TRANSITION_SNAP_HZ) {
+    if (freq_hz == 0) return MOTO_NONE;
+    uint32_t best_idx = MOTO_NONE;
+    uint32_t best_diff = match_hz + 1;
+    for (size_t i = 0; i < 45; i++) {
+        const uint32_t hz = MOTO_FREQS[i] / 10;
+        const uint32_t diff = (freq_hz > hz) ? (freq_hz - hz) : (hz - freq_hz);
+        if (diff < best_diff) {
+            best_diff = diff;
+            best_idx = i;
+        }
+    }
+    return best_idx;
+}
+
+// Format a detected tone for display, snapping to nearest MOTO table entry.
+static std::string format_tone(uint32_t freq_hz, uint32_t duration_ms) {
+    const uint32_t idx = moto_index(freq_hz, MOTO_FINAL_MATCH_HZ);
+    std::string freq_str;
+    if (idx != MOTO_NONE) {
+        const uint32_t matched_x10 = MOTO_FREQS[idx];
+        freq_str = to_string_dec_uint(matched_x10 / 10) + "." +
+                   to_string_dec_uint(matched_x10 % 10) + "Hz";
+    } else {
+        freq_str = to_string_dec_uint(freq_hz) + "Hz";
+    }
+    return freq_str + " " + to_string_dec_uint(duration_ms) + "ms";
+}
+
+// ---------------------------------------------------------------------------
+// Waterfall rect
+// ---------------------------------------------------------------------------
+static constexpr ui::Rect waterfall_rect{0, waterfall_top, screen_width_px, waterfall_height};
+
+// ---------------------------------------------------------------------------
+// TwoToneRxView
+// ---------------------------------------------------------------------------
+
+void TwoToneRxView::focus() {
+    button_startstop.focus();
+}
+
+void TwoToneRxView::on_hide() {
+    if (running_) stop_rx();
+}
+
+TwoToneRxView::TwoToneRxView(NavigationView& nav)
+    : nav_{nav} {
+    prior_antenna_bias_ = get_antenna_bias();
+    debug_file_.append(u"DEBUG/TWOTONERX.TXT");
+    debug_file_.write_entry("==== two_tone_rx session start ====");
+
+    add_children({
+        &field_frequency,
+        &field_rf_amp,
+        &field_lna,
+        &field_vga,
+        &rssi,
+        &field_volume,
+        &labels,
+        &options_ctcss,
+        &field_squelch,
+        &button_startstop,
+        &button_clear,
+        &text_status,
+        &check_bias_t,
+        &tone_log_view,
+    });
+
+    // Populate CTCSS options
+    using opt_t = std::pair<std::string, int32_t>;
+    options_ctcss.set_options([&]() {
+        std::vector<opt_t> opts;
+        opts.reserve(51);
+        for (size_t i = 0; i < 51; i++)
+            opts.push_back({ctcss_name(CTCSS_FREQS[i]), (int32_t)i});
+        return opts;
+    }());
+    options_ctcss.set_by_value((int32_t)ctcss_idx);
+    options_ctcss.on_change = [this](size_t, int32_t v) {
+        ctcss_idx = (uint32_t)v;
+        if (running_) baseband::set_tonedetect_config((uint8_t)squelch_val, CTCSS_FREQS[ctcss_idx]);
+    };
+
+    field_squelch.set_value((int32_t)squelch_val);
+    field_squelch.on_change = [this](int32_t v) {
+        squelch_val = (uint32_t)v;
+        if (running_) baseband::set_tonedetect_config((uint8_t)squelch_val, CTCSS_FREQS[ctcss_idx]);
+    };
+
+    button_startstop.on_select = [this](Button&) {
+        if (running_)
+            stop_rx();
+        else
+            start_rx();
+    };
+
+    button_clear.on_select = [this](Button&) {
+        tone_log_entries_.clear();
+        tone_log_view.set_dirty();
+        text_status.set("");
+        reset_detect_state();
+    };
+
+    check_bias_t.set_value(bias_t_enabled);
+    check_bias_t.on_select = [this](Checkbox&, bool v) {
+        bias_t_enabled = v;
+        apply_bias_t(running_);
+    };
+
+    field_frequency.set_step(12500);
+    tone_log_view.set_parent_rect(tone_log_rect);
+}
+
+TwoToneRxView::~TwoToneRxView() {
+    if (running_) stop_rx();
+}
+
+void TwoToneRxView::reset_detect_state() {
+    detect_state_ = DetectState::IDLE;
+    phase_window_count_ = 0;
+    phase_freq_accum_ = 0;
+    phase_valid_windows_ = 0;
+    phase_last_freq_ = 0;
+    phase_last_is_first_ = true;
+    t1_avg_freq_ = 0;
+    t1_window_count_ = 0;
+    t1_transition_candidate_windows_ = 0;
+    t2_zero_window_count_ = 0;
+    debug_trace_active_ = false;
+    debug_trace_id_ = 0;
+}
+
+void TwoToneRxView::start_rx() {
+    baseband::run_prepared_image(portapack::memory::map::m4_code.base());
+
+    audio::set_rate(audio::Rate::Hz_24000);
+    audio::output::start();
+
+    receiver_model.set_hidden_offset(0);
+    receiver_model.set_sampling_rate(3072000);
+    receiver_model.set_baseband_bandwidth(1750000);
+    receiver_model.enable();
+    apply_bias_t(true);
+
+    baseband::set_tonedetect_config((uint8_t)squelch_val, CTCSS_FREQS[ctcss_idx]);
+
+    add_child(&waterfall);
+    waterfall.set_parent_rect(waterfall_rect);
+
+    running_ = true;
+    button_startstop.set_text("Stop");
+    text_status.set("");
+}
+
+void TwoToneRxView::stop_rx() {
+    remove_child(&waterfall);
+
+    apply_bias_t(false);
+    receiver_model.disable();
+    baseband::shutdown();
+    audio::output::stop();
+
+    running_ = false;
+    button_startstop.set_text("Start");
+    text_status.set("");
+    reset_detect_state();
+}
+
+void TwoToneRxView::apply_bias_t(bool active) {
+    if (active && bias_t_enabled) {
+        set_antenna_bias(true);
+        receiver_model.set_antenna_bias();
+        applied_bias_t_ = true;
+        return;
+    }
+
+    if (!applied_bias_t_) return;
+
+    set_antenna_bias(prior_antenna_bias_);
+    receiver_model.set_antenna_bias();
+    applied_bias_t_ = false;
+}
+
+void TwoToneRxView::debug_log(const std::string& line) {
+    const std::string trace_prefix = debug_trace_active_
+                                         ? ("#" + to_string_dec_uint(debug_trace_id_) + " ")
+                                         : "";
+    const std::string entry = "[D] " + trace_prefix + line;
+    debug_file_.write_entry(entry);
+}
+
+void TwoToneRxView::debug_trace_begin(const std::string& line) {
+    if (!debug_trace_active_) {
+        debug_trace_id_ = ++debug_trace_counter_;
+        debug_trace_active_ = true;
+    }
+    debug_log(line);
+}
+
+void TwoToneRxView::finalize_detected_pair(uint32_t t2_avg, uint32_t t2_dur, const char* reason) {
+    const uint32_t t1_dur = t1_window_count_ * DETECT_WINDOW_MS;
+    const std::string suffix = std::string(" via ") + reason;
+
+    if (t1_avg_freq_ > 0 && t2_avg > 0 &&
+        t1_dur >= 500 && t2_dur >= 500 &&
+        moto_index(t1_avg_freq_, MOTO_FINAL_MATCH_HZ) != MOTO_NONE &&
+        moto_index(t2_avg, MOTO_FINAL_MATCH_HZ) != MOTO_NONE) {
+        debug_trace_begin("END ok T1=" + format_tone(t1_avg_freq_, t1_dur) +
+                          " T2=" + format_tone(t2_avg, t2_dur) + suffix);
+        log_tone_pair(t1_avg_freq_, t1_dur, t2_avg, t2_dur);
+    } else {
+        debug_trace_begin("END drop T1=" + format_tone(t1_avg_freq_, t1_dur) +
+                          " T2=" + format_tone(t2_avg, t2_dur) + suffix);
+    }
+}
+
+// ---------------------------------------------------------------------------
+// on_tone_data — window-based two-tone detection state machine
+//
+// Every 40 ms the baseband sends tone_end=false with a raw frequency estimate
+// for that window (freq_hz=0 if no stable QCII candidate).
+// When the CTCSS gate closes it sends tone_end=true (freq_hz=0).
+//
+// First and last windows of each phase are discarded:
+//   - "First" is tracked with phase_last_is_first_.
+//   - "Last" is phase_last_freq_, never added to the accumulator while
+//     pending; discarded when the phase ends.
+//
+// T1→T2 transition: consecutive windows that snap to different MOTO table
+// entries. The transition window becomes T2's first window.
+//
+// Final matching is done from the phase-average raw estimates collected here,
+// not from the per-window nearest-table snap used for transition detection.
+// ---------------------------------------------------------------------------
+void TwoToneRxView::on_tone_data(const ToneDetectDataMessage* msg) {
+    if (!running_) return;
+
+    if (msg->tone_end) {
+        // Gate closed — finalize whatever phase we're in
+        if (detect_state_ == DetectState::T2_COLLECTING) {
+            // phase_last_freq_ is the last T2 window → discard it
+            uint32_t t2_avg = (phase_valid_windows_ > 0)
+                                  ? (phase_freq_accum_ / phase_valid_windows_)
+                                  : phase_last_freq_;
+            uint32_t t2_dur = phase_window_count_ * DETECT_WINDOW_MS;
+            finalize_detected_pair(t2_avg, t2_dur, "tone_end");
+        } else if (debug_trace_active_) {
+            debug_log("END before T2");
+        }
+        reset_detect_state();
+        text_status.set("");
+        return;
+    }
+
+    // tone_end=false: this is a 40 ms measurement window
+    const uint32_t freq = msg->freq_hz;
+    if (freq == 0) {
+        if (detect_state_ == DetectState::T2_COLLECTING) {
+            const uint32_t t2_avg = (phase_valid_windows_ > 0)
+                                        ? (phase_freq_accum_ / phase_valid_windows_)
+                                        : phase_last_freq_;
+            const uint32_t t2_dur = phase_window_count_ * DETECT_WINDOW_MS;
+
+            if (t2_avg > 0 && t2_dur >= 2000) {
+                finalize_detected_pair(t2_avg, t2_dur, "t2_break");
+                reset_detect_state();
+                text_status.set("");
+                return;
+            }
+        }
+
+        // A single weak/noisy dropout is tolerated during T2 so standard 3 s
+        // B tones are not lost to one marginal 40 ms estimate window.
+        if (detect_state_ == DetectState::T2_COLLECTING && t2_zero_window_count_ == 0) {
+            t2_zero_window_count_++;
+            if (debug_trace_active_) {
+                debug_log("T2 zero dropout");
+            }
+            text_status.set("T1:" + format_tone(t1_avg_freq_, t1_window_count_ * DETECT_WINDOW_MS) +
+                            " T2 ?");
+            return;
+        }
+
+        // Otherwise, treat the missing estimate as a break in the sequence.
+        if (debug_trace_active_) {
+            debug_log("RESET zero");
+        }
+        reset_detect_state();
+        text_status.set("");
+        return;
+    }
+
+    t2_zero_window_count_ = 0;
+
+    switch (detect_state_) {
+        case DetectState::IDLE:
+            detect_state_ = DetectState::T1_COLLECTING;
+            phase_window_count_ = 1;
+            phase_freq_accum_ = 0;
+            phase_valid_windows_ = 0;
+            phase_last_freq_ = freq;
+            phase_last_is_first_ = true;
+            text_status.set("T1 ...");
+            break;
+
+        case DetectState::T1_COLLECTING: {
+            // Check for T1→T2 MOTO index transition.
+            // Skip if phase_last_freq_ is the first (noisy) window — it's
+            // marked for discard and must not trigger a false transition.
+            if (freq > 0 && phase_last_freq_ > 0 && !phase_last_is_first_) {
+                const uint32_t t1_ref_freq = (phase_valid_windows_ > 0)
+                                                 ? (phase_freq_accum_ / phase_valid_windows_)
+                                                 : phase_last_freq_;
+                const uint32_t idx_ref = moto_index(t1_ref_freq, MOTO_FINAL_MATCH_HZ);
+                const uint32_t idx_last = moto_index(phase_last_freq_);
+                const uint32_t idx_cur = moto_index(freq);
+                const uint32_t idx_cur_final = moto_index(freq, MOTO_FINAL_MATCH_HZ);
+
+                bool transition_detected = false;
+                if (idx_last != MOTO_NONE && idx_cur != MOTO_NONE && idx_last != idx_cur) {
+                    if (!debug_trace_active_) {
+                        debug_trace_begin("T1 start " + format_tone(t1_ref_freq, phase_window_count_ * DETECT_WINDOW_MS));
+                    }
+                    debug_log("T1->T2 snap " + format_tone(phase_last_freq_, DETECT_WINDOW_MS) +
+                              " -> " + format_tone(freq, DETECT_WINDOW_MS));
+                    transition_detected = true;
+                } else if (idx_ref != MOTO_NONE &&
+                           idx_cur_final != MOTO_NONE &&
+                           idx_cur_final != idx_ref &&
+                           abs_diff_u32(freq, t1_ref_freq) >= MOTO_TRANSITION_DELTA_HZ) {
+                    t1_transition_candidate_windows_++;
+                    if (debug_trace_active_) {
+                        debug_log("T1 cand " + to_string_dec_uint(t1_transition_candidate_windows_) +
+                                  " ref=" + to_string_dec_uint(t1_ref_freq) +
+                                  " cur=" + to_string_dec_uint(freq));
+                    }
+                    transition_detected = (t1_transition_candidate_windows_ >= 2);
+                } else {
+                    if (debug_trace_active_ && t1_transition_candidate_windows_ > 0) {
+                        debug_log("T1 cand reset");
+                    }
+                    t1_transition_candidate_windows_ = 0;
+                }
+
+                if (transition_detected) {
+                    // Transition detected.
+                    // phase_last_freq_ is the last T1 window → discard.
+                    t1_avg_freq_ = (phase_valid_windows_ > 0)
+                                       ? (phase_freq_accum_ / phase_valid_windows_)
+                                       : phase_last_freq_;
+                    t1_window_count_ = phase_window_count_;
+
+                    // Start T2 with current window as first (also discarded)
+                    detect_state_ = DetectState::T2_COLLECTING;
+                    phase_window_count_ = 1;
+                    phase_freq_accum_ = 0;
+                    phase_valid_windows_ = 0;
+                    phase_last_freq_ = freq;
+                    phase_last_is_first_ = true;
+                    t1_transition_candidate_windows_ = 0;
+                    t2_zero_window_count_ = 0;
+
+                    if (!debug_trace_active_) {
+                        debug_trace_begin("T1 start " + format_tone(t1_avg_freq_, t1_window_count_ * DETECT_WINDOW_MS));
+                    }
+                    debug_log("T2 start " + format_tone(freq, DETECT_WINDOW_MS));
+                    text_status.set("T1:" + format_tone(t1_avg_freq_, t1_window_count_ * DETECT_WINDOW_MS) + " T2...");
+                    break;
+                }
+            }
+
+            // No transition: promote pending window into accumulator (unless first)
+            if (!phase_last_is_first_ && phase_last_freq_ > 0) {
+                phase_freq_accum_ += phase_last_freq_;
+                phase_valid_windows_++;
+            }
+            phase_last_freq_ = freq;
+            phase_last_is_first_ = false;
+            phase_window_count_++;
+
+            if (!debug_trace_active_ &&
+                phase_window_count_ >= 3 &&
+                moto_index(phase_last_freq_, MOTO_FINAL_MATCH_HZ) != MOTO_NONE) {
+                const uint32_t t1_ref_freq = (phase_valid_windows_ > 0)
+                                                 ? (phase_freq_accum_ / phase_valid_windows_)
+                                                 : phase_last_freq_;
+                debug_trace_begin("T1 start " + format_tone(t1_ref_freq, phase_window_count_ * DETECT_WINDOW_MS));
+            }
+
+            text_status.set("T1 " + to_string_dec_uint(phase_window_count_ * DETECT_WINDOW_MS) + "ms...");
+            break;
+        }
+
+        case DetectState::T2_COLLECTING:
+            // Promote pending window into accumulator (unless first)
+            if (!phase_last_is_first_ && phase_last_freq_ > 0) {
+                phase_freq_accum_ += phase_last_freq_;
+                phase_valid_windows_++;
+            }
+            phase_last_freq_ = freq;
+            phase_last_is_first_ = false;
+            phase_window_count_++;
+
+            text_status.set("T1:" + format_tone(t1_avg_freq_, t1_window_count_ * DETECT_WINDOW_MS) +
+                            " T2 " + to_string_dec_uint(phase_window_count_ * DETECT_WINDOW_MS) + "ms");
+            break;
+    }
+}
+
+void TwoToneRxView::log_tone_pair(uint32_t f1, uint32_t d1_ms, uint32_t f2, uint32_t d2_ms) {
+    // Keep the oldest entry at the top so newer pairs appear below it.
+    tone_log_entries_.push_back({++next_log_serial_, format_tone(f1, d1_ms) + " " + format_tone(f2, d2_ms)});
+    tone_log_view.set_dirty();
+}
+
+}  // namespace ui::external_app::two_tone_rx
+
+namespace ui {
+
+template <>
+void RecentEntriesTable<ui::external_app::two_tone_rx::TwoToneLogEntries>::draw(
+    const Entry& entry,
+    const Rect& target_rect,
+    Painter& painter,
+    const Style& style,
+    ui::RecentEntriesColumns&) {
+    std::string line = entry.line;
+    line.resize(target_rect.width() / 8, ' ');
+    painter.draw_string(target_rect.location(), style, line);
+}
+
+}  // namespace ui

firmware/application/external/two_tone_rx/ui_two_tone_rx.hpp

@@ -0,0 +1,214 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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_TWO_TONE_RX_H__
+#define __UI_TWO_TONE_RX_H__
+
+#include "ui.hpp"
+#include "ui_navigation.hpp"
+#include "ui_receiver.hpp"
+#include "ui_freq_field.hpp"
+#include "ui_spectrum.hpp"
+#include "app_settings.hpp"
+#include "radio_state.hpp"
+#include "message.hpp"
+#include "string_format.hpp"
+#include "log_file.hpp"
+#include "recent_entries.hpp"
+
+namespace ui::external_app::two_tone_rx {
+
+struct TwoToneLogEntry {
+    using Key = uint32_t;
+
+    static constexpr Key invalid_key = 0;
+
+    Key serial{};
+    std::string line{};
+
+    Key key() const { return serial; }
+};
+
+using TwoToneLogEntries = RecentEntries<TwoToneLogEntry>;
+
+class TwoToneRxView : public View {
+   public:
+    TwoToneRxView(NavigationView& nav);
+    ~TwoToneRxView();
+
+    TwoToneRxView(const TwoToneRxView&) = delete;
+    TwoToneRxView(TwoToneRxView&&) = delete;
+    TwoToneRxView& operator=(const TwoToneRxView&) = delete;
+    TwoToneRxView& operator=(TwoToneRxView&&) = delete;
+
+    void focus() override;
+    void on_hide() override;
+    std::string title() const override { return "2-Tone RX"; };
+
+   private:
+    NavigationView& nav_;
+
+    RxRadioState radio_state_{};
+
+    bool running_{false};
+
+    TwoToneLogEntries tone_log_entries_{};
+    uint32_t next_log_serial_{0};
+
+    uint32_t squelch_val{50};
+    uint32_t ctcss_idx{0};
+    bool bias_t_enabled{false};
+    bool prior_antenna_bias_{false};
+    bool applied_bias_t_{false};
+    LogFile debug_file_{};
+
+    app_settings::SettingsManager settings_{
+        "rx_twotone",
+        app_settings::Mode::RX,
+        {
+            {"tone_sq"sv, &squelch_val},
+            {"ctcss"sv, &ctcss_idx},
+            {"bias_t"sv, &bias_t_enabled},
+        }};
+
+    void start_rx();
+    void stop_rx();
+    void apply_bias_t(bool active);
+    void debug_log(const std::string& line);
+    void debug_trace_begin(const std::string& line);
+    void on_tone_data(const ToneDetectDataMessage* msg);
+    void log_tone_pair(uint32_t f1, uint32_t d1_ms, uint32_t f2, uint32_t d2_ms);
+    void finalize_detected_pair(uint32_t t2_avg, uint32_t t2_dur, const char* reason);
+    void reset_detect_state();
+
+    // ── Two-tone detection state machine ─────────────────────────────────────
+    //
+    // Each 40 ms measurement window from the baseband arrives as tone_end=false.
+    // tone_end=true signals that the CTCSS gate closed (end of transmission).
+    //
+    // Collection rule: discard first and last window of each phase.
+    //   - "First" is always discarded (may contain carrier ramp-up).
+    //   - "Last" is never added to the accumulator while pending; it is
+    //     discarded when the next window confirms it is not the last, OR when
+    //     the phase ends (tone_end=true or T1→T2 transition).
+    //
+    // Transition detection: two consecutive windows that snap to different MOTO
+    // table entries trigger T1→T2. The transition window becomes T2's first
+    // window (also discarded as T2's first).
+
+    enum class DetectState : uint8_t { IDLE,
+                                       T1_COLLECTING,
+                                       T2_COLLECTING };
+    DetectState detect_state_{DetectState::IDLE};
+
+    // Per-phase window collection
+    uint32_t phase_window_count_{0};   // total windows seen in this phase (including first)
+    uint32_t phase_freq_accum_{0};     // sum of non-first, non-last window frequencies
+    uint32_t phase_valid_windows_{0};  // count of windows in phase_freq_accum_
+    uint32_t phase_last_freq_{0};      // pending window (not yet added; discarded if last)
+    bool phase_last_is_first_{true};   // true when phase_last_freq_ is window 1 (discard)
+
+    // T1 result (stored at T1→T2 transition for use when pair is logged)
+    uint32_t t1_avg_freq_{0};
+    uint32_t t1_window_count_{0};
+    uint8_t t1_transition_candidate_windows_{0};
+    uint8_t t2_zero_window_count_{0};
+    bool debug_trace_active_{false};
+    uint32_t debug_trace_id_{0};
+    uint32_t debug_trace_counter_{0};
+
+    // ── Row 0: frequency + RF controls ───────────────────────────────────────
+
+    RxFrequencyField field_frequency{
+        {UI_POS_X(0), UI_POS_Y(0)},
+        nav_};
+    RFAmpField field_rf_amp{
+        {UI_POS_X(13), UI_POS_Y(0)}};
+    LNAGainField field_lna{
+        {UI_POS_X(15), UI_POS_Y(0)}};
+    VGAGainField field_vga{
+        {UI_POS_X(18), UI_POS_Y(0)}};
+    RSSI rssi{
+        {UI_POS_X(21), UI_POS_Y(0), UI_POS_WIDTH_REMAINING(24), 4}};
+    AudioVolumeField field_volume{
+        {UI_POS_X_RIGHT(2), UI_POS_Y(0)}};
+
+    // ── Row 1: CTCSS / Squelch / Start+Stop / Clear ──────────────────────────
+
+    Labels labels{
+        {{0 * 8, 1 * 16}, "CTCSS:", Theme::getInstance()->fg_light->foreground},
+        {{15 * 8, 1 * 16}, "Sq:", Theme::getInstance()->fg_light->foreground},
+    };
+
+    OptionsField options_ctcss{
+        {7 * 8, 1 * 16},
+        8,
+        {}};
+
+    NumberField field_squelch{
+        {19 * 8, 1 * 16},
+        2,
+        {0, 99},
+        1,
+        ' '};
+
+    Button button_startstop{
+        {21 * 8, 1 * 16, 5 * 8, 18},
+        "Start"};
+
+    Button button_clear{
+        {26 * 8, 1 * 16, 4 * 8, 18},
+        "Clr"};
+
+    // ── Row 2: live status (active tone in progress) + Bias-T toggle ─────────
+
+    Text text_status{
+        {0, 2 * 16 + 4, 20 * 8, 16},
+        ""};
+
+    Checkbox check_bias_t{
+        {20 * 8, 2 * 16 + 2},
+        9,
+        "Bias-T",
+        true};
+
+    ui::RecentEntriesColumns tone_log_columns{{
+        {"Tones", 0},
+    }};
+    ui::RecentEntriesTable<TwoToneLogEntries> tone_log_view{tone_log_entries_, tone_log_columns};
+
+    // ── Waterfall (rest of screen) ────────────────────────────────────────────
+
+    spectrum::WaterfallView waterfall{};
+
+    // ── Message handler ───────────────────────────────────────────────────────
+
+    MessageHandlerRegistration message_handler_tone{
+        Message::ID::ToneDetectData,
+        [this](const Message* const p) {
+            const auto* msg = reinterpret_cast<const ToneDetectDataMessage*>(p);
+            this->on_tone_data(msg);
+        }};
+};
+
+}  // namespace ui::external_app::two_tone_rx
+
+#endif /* __UI_TWO_TONE_RX_H__ */

firmware/baseband/CMakeLists.txt

@@ -683,6 +683,14 @@ set(MODE_CPPSRC
 )
 DeclareTargets(PSCD subcar)
 
+### Tone Detect RX
+
+set(MODE_CPPSRC
+    proc_tonedetect.cpp
+)
+DeclareTargets(PTNE tonedetect)
+
+
 ### Morse RX Decoder
 
 set(MODE_CPPSRC

firmware/baseband/proc_tonedetect.cpp

@@ -0,0 +1,332 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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_tonedetect.hpp"
+#include "audio_dma.hpp"
+#include "portapack_shared_memory.hpp"
+#include "event_m4.hpp"
+#include <cmath>
+
+static constexpr float SAMPLE_RATE = 24000.0f;
+static constexpr uint32_t WINDOW_SAMPLES = 960;  // 40 ms at 24 kHz (30 execute() calls)
+static constexpr uint32_t WINDOW_MS = (1000 * WINDOW_SAMPLES) / (uint32_t)SAMPLE_RATE;
+static constexpr uint32_t AUDIO_BLOCK_SAMPLES = 32;  // demod_fm emits 32 audio samples per execute()
+static constexpr uint32_t SQUELCH_HOLD_BLOCKS =
+    (100 * (uint32_t)SAMPLE_RATE) / (1000 * AUDIO_BLOCK_SAMPLES);  // 100 ms hold at execute() block rate
+static constexpr float PI_F = 3.14159265f;
+
+// Motorola/EIA QCII paging frequencies (×10 to avoid float in table)
+static constexpr uint32_t MOTO_FREQS_X10[45] = {
+    2885,
+    3047,
+    3217,
+    3396,
+    3586,
+    3786,
+    3998,
+    4221,
+    4457,
+    4705,
+    4968,
+    5246,
+    5539,
+    5848,
+    6174,
+    6519,
+    6883,
+    7268,
+    7674,
+    8102,
+    8555,
+    9032,
+    9537,
+    10073,
+    10642,
+    11225,
+    11247,
+    11534,
+    11852,
+    11885,
+    12178,
+    12514,
+    12555,
+    12858,
+    13258,
+    13576,
+    13950,
+    13996,
+    14768,
+    15579,
+    16430,
+    17325,
+    18262,
+    19245,
+    20275,
+};
+
+// Minimum coherent Goertzel energy for MOTO tone detection.
+// For amplitude A over WINDOW_SAMPLES: energy ≈ (A × N/2)² = (A × 240)².
+// Threshold 1000 → requires A > ~13% of FM demod full scale (~650 Hz deviation).
+// Set high enough that FM broadband noise (σ ≈ 0.3, expected per-bin energy ≈ 43)
+// never triggers a false detection even when the carrier gate is briefly open.
+static constexpr float MOTO_ENERGY_THRESHOLD = 1000.0f;
+
+// Fixed carrier-detect threshold for the detection gate (independent of user squelch).
+// FMSquelch returns true when HF noise is BELOW this value (= FM carrier present).
+// 0.20 opens reliably on any clean FM carrier without false-opening on noise.
+static constexpr float CARRIER_DETECT_THRESHOLD = 0.20f;
+
+// Goertzel energy threshold for CTCSS detection.
+// Pure CTCSS at 5% amplitude over 960 samples → energy ≈ (0.05 × 480)² = 576.
+static constexpr float CTCSS_ENERGY_THRESHOLD = 30.0f;
+
+void ToneDetectProcessor::configure(uint8_t squelch, uint32_t ctcss_f_x10) {
+    configured = false;
+    user_squelch_level = squelch;
+    ctcss_freq_x10 = ctcss_f_x10;
+
+    decim_0.configure(taps_11k0_decim_0.taps);
+    decim_1.configure(taps_11k0_decim_1.taps);
+    channel_filter.configure(taps_11k0_channel.taps, 2);
+    demod_fm.configure(24000, 5000);
+    audio_output.configure(false);
+    fm_squelch.set_threshold((float)user_squelch_level / 100.0f);
+    channel_spectrum.set_decimation_factor(1);
+
+    // Precompute Goertzel coefficient for CTCSS (if active).
+    // k = nearest DFT bin for the CTCSS frequency over WINDOW_SAMPLES.
+    if (ctcss_freq_x10 > 0) {
+        const float freq = (float)ctcss_freq_x10 / 10.0f;
+        const float k = roundf((float)WINDOW_SAMPLES * freq / SAMPLE_RATE);
+        const float omega = 2.0f * PI_F * k / (float)WINDOW_SAMPLES;
+        goertzel_coeff = 2.0f * cosf(omega);
+    } else {
+        goertzel_coeff = 0.0f;
+    }
+
+    // Precompute Goertzel coefficients for all 45 MOTO frequencies.
+    // Each filter is tuned to the EXACT MOTO frequency (not the nearest DFT bin center)
+    // so that every entry has a unique coefficient and maximum energy only at its
+    // specific frequency.  This eliminates bin-sharing ambiguity and gives the best
+    // discrimination between close entries such as 1357.6 Hz and 1395.0 Hz.
+    for (size_t i = 0; i < 45; i++) {
+        const float freq = (float)MOTO_FREQS_X10[i] / 10.0f;
+        const float omega = 2.0f * PI_F * freq / SAMPLE_RATE;
+        moto_coeff[i] = 2.0f * cosf(omega);
+        moto_s1[i] = 0.0f;
+        moto_s2[i] = 0.0f;
+    }
+
+    // Fixed carrier-detect squelch — threshold never changes with user settings.
+    carrier_sq.set_threshold(CARRIER_DETECT_THRESHOLD);
+
+    // Reset all per-window state
+    goertzel_s1 = 0.0f;
+    goertzel_s2 = 0.0f;
+    window_sample_count = 0;
+    was_ctcss_detected = false;
+    tone_duration_windows = 0;
+    squelch_is_open = false;
+    squelch_hold = 0;
+    carrier_is_open = false;
+    carrier_hold = 0;
+
+    configured = true;
+}
+
+void ToneDetectProcessor::execute(const buffer_c8_t& buffer) {
+    if (!configured) return;
+
+    const auto decim_0_out = decim_0.execute(buffer, dst_buffer);
+    const auto decim_1_out = decim_1.execute(decim_0_out, dst_buffer);
+
+    // Feed IQ data into spectrum collector for the RF waterfall.
+    channel_spectrum.feed(decim_1_out, -5500, 5500, 3400);
+
+    const auto channel_out = channel_filter.execute(decim_1_out, dst_buffer);
+    auto audio_buf = demod_fm.execute(channel_out, audio_buffer);
+
+    // --- Audio muting squelch (user-adjustable level) ---
+    // FMSquelch returns true when HF noise is LOW (carrier present).
+    const bool fm_open = fm_squelch.execute(audio_buf);
+    if (fm_open) {
+        squelch_hold = SQUELCH_HOLD_BLOCKS;
+        squelch_is_open = true;
+    } else if (squelch_hold > 0) {
+        squelch_hold--;
+    } else {
+        squelch_is_open = false;
+    }
+
+    // --- Fixed carrier-detect gate (independent of user squelch level) ---
+    // carrier_sq always uses CARRIER_DETECT_THRESHOLD (0.20) regardless of squelch_val.
+    // This ensures the detection gate closes when the carrier disappears even when the
+    // user sets squelch=0 (always-open audio), preventing the state machine from
+    // accumulating noise windows or getting stuck between transmissions.
+    const bool carrier_raw = carrier_sq.execute(audio_buf);
+    if (carrier_raw) {
+        carrier_hold = SQUELCH_HOLD_BLOCKS;
+        carrier_is_open = true;
+    } else if (carrier_hold > 0) {
+        carrier_hold--;
+    } else {
+        carrier_is_open = false;
+    }
+
+    for (size_t i = 0; i < audio_buf.count; i++) {
+        const float s = audio_buf.p[i];
+
+        // Mute audio output when FM squelch is closed (does not affect Goertzel).
+        if (!squelch_is_open) audio_buf.p[i] = 0.0f;
+
+        // CTCSS Goertzel step (CTCSS mode only).
+        // Uses original unmuted sample so CTCSS energy is unaffected by audio muting.
+        if (ctcss_freq_x10 > 0) {
+            const float s0 = s + goertzel_coeff * goertzel_s1 - goertzel_s2;
+            goertzel_s2 = goertzel_s1;
+            goertzel_s1 = s0;
+        }
+
+        // MOTO frequency bank — Goertzel step for all 45 MOTO bins.
+        // Runs unconditionally so the full window always contributes to energy.
+        // Benefit over zero-crossing: coherent detection, no warm-up period,
+        // accurate on the very first window after the gate opens.
+        for (size_t j = 0; j < 45; j++) {
+            const float s0 = s + moto_coeff[j] * moto_s1[j] - moto_s2[j];
+            moto_s2[j] = moto_s1[j];
+            moto_s1[j] = s0;
+        }
+
+        // Window boundary: every WINDOW_SAMPLES samples = one 40 ms estimate window
+        if (++window_sample_count >= WINDOW_SAMPLES) {
+            window_sample_count = 0;
+
+            // --- Detection gate ---
+            // Carrier presence (carrier_is_open) is always required — without it,
+            // the FM demod outputs broadband noise that floods every Goertzel bin and
+            // triggers false detections regardless of the CTCSS threshold.
+            // CTCSS mode adds a second requirement: coherent CTCSS energy must also
+            // be present.  This is the standard two-condition squelch used in real radios.
+            bool gate_open;
+            if (ctcss_freq_x10 > 0) {
+                const float power = goertzel_s1 * goertzel_s1 + goertzel_s2 * goertzel_s2 - goertzel_coeff * goertzel_s1 * goertzel_s2;
+                gate_open = carrier_is_open && (power > CTCSS_ENERGY_THRESHOLD);
+                goertzel_s1 = 0.0f;
+                goertzel_s2 = 0.0f;
+            } else {
+                gate_open = carrier_is_open;
+            }
+
+            // --- MOTO frequency identification via Goertzel energy ---
+            // Find the MOTO table entry with the highest coherent energy this window.
+            // Reset all states regardless of gate so each window starts fresh.
+            float energies[45]{};
+            uint32_t best_idx = 45;  // 45 = sentinel (no match)
+            float best_energy = MOTO_ENERGY_THRESHOLD;
+            for (size_t j = 0; j < 45; j++) {
+                const float pwr = moto_s1[j] * moto_s1[j] + moto_s2[j] * moto_s2[j] - moto_coeff[j] * moto_s1[j] * moto_s2[j];
+                energies[j] = pwr;
+                moto_s1[j] = 0.0f;
+                moto_s2[j] = 0.0f;
+                if (pwr > best_energy) {
+                    best_energy = pwr;
+                    best_idx = j;
+                }
+            }
+            // Report a raw estimate from the local energy centroid around the best
+            // entry, and let the UI do the final table snap from the phase average.
+            uint32_t win_freq_hz = 0;
+            if (best_idx < 45) {
+                const size_t start = (best_idx > 0) ? (best_idx - 1) : best_idx;
+                const size_t end = (best_idx + 1 < 45) ? (best_idx + 1) : best_idx;
+                float weight_sum = 0.0f;
+                float weighted_freq_x10 = 0.0f;
+                for (size_t j = start; j <= end; j++) {
+                    const float weight = energies[j] - MOTO_ENERGY_THRESHOLD;
+                    if (weight > 0.0f) {
+                        weight_sum += weight;
+                        weighted_freq_x10 += weight * (float)MOTO_FREQS_X10[j];
+                    }
+                }
+                if (weight_sum > 0.0f) {
+                    win_freq_hz = (uint32_t)((weighted_freq_x10 / weight_sum) / 10.0f + 0.5f);
+                } else {
+                    win_freq_hz = MOTO_FREQS_X10[best_idx] / 10;
+                }
+            }
+
+            if (gate_open) {
+                if (!was_ctcss_detected) {
+                    tone_duration_windows = 0;
+                }
+                tone_duration_windows++;
+                was_ctcss_detected = true;
+
+                data_message.freq_hz = win_freq_hz;
+                data_message.duration_ms = tone_duration_windows * WINDOW_MS;
+                data_message.tone_end = false;
+                shared_memory.application_queue.push(data_message);
+
+            } else {
+                if (was_ctcss_detected) {
+                    // Gate just closed — signal tone end to application
+                    data_message.freq_hz = 0;
+                    data_message.duration_ms = tone_duration_windows * WINDOW_MS;
+                    data_message.tone_end = true;
+                    shared_memory.application_queue.push(data_message);
+                    tone_duration_windows = 0;
+                }
+                was_ctcss_detected = false;
+            }
+        }
+    }
+
+    audio_output.write(audio_buf);
+}
+
+void ToneDetectProcessor::on_message(const Message* const p) {
+    switch (p->id) {
+        case Message::ID::ToneDetectConfig: {
+            const auto& msg = *reinterpret_cast<const ToneDetectConfigureMessage*>(p);
+            configure(msg.squelch_level, msg.ctcss_freq_x10);
+            break;
+        }
+        case Message::ID::NBFMConfigure: {
+            const auto& msg = *reinterpret_cast<const NBFMConfigureMessage*>(p);
+            user_squelch_level = msg.squelch_level;
+            fm_squelch.set_threshold((float)user_squelch_level / 100.0f);
+            break;
+        }
+        case Message::ID::UpdateSpectrum:
+        case Message::ID::SpectrumStreamingConfig:
+            channel_spectrum.on_message(p);
+            break;
+        default:
+            break;
+    }
+}
+
+int main() {
+    audio::dma::init_audio_out();
+    EventDispatcher event_dispatcher{std::make_unique<ToneDetectProcessor>()};
+    event_dispatcher.run();
+    return 0;
+}

firmware/baseband/proc_tonedetect.hpp

@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2024 PortaPack Mayhem
+ *
+ * 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_TONEDETECT_H__
+#define __PROC_TONEDETECT_H__
+
+#include "baseband_processor.hpp"
+#include "baseband_thread.hpp"
+#include "message.hpp"
+#include "dsp_decimate.hpp"
+#include "dsp_demodulate.hpp"
+#include "audio_output.hpp"
+#include "dsp_fir_taps.hpp"
+#include "rssi_thread.hpp"
+#include "spectrum_collector.hpp"
+#include "dsp_squelch.hpp"
+
+class ToneDetectProcessor : public BasebandProcessor {
+   public:
+    ToneDetectProcessor() {}
+
+    void execute(const buffer_c8_t& buffer) override;
+    void on_message(const Message* const p) override;
+
+   private:
+    void configure(uint8_t squelch, uint32_t ctcss_freq_x10);
+
+    BasebandThread baseband_thread{3072000, this, baseband::Direction::Receive};
+    RSSIThread rssi_thread{};
+
+    std::array<complex16_t, 512> dst{};
+    const buffer_c16_t dst_buffer{dst.data(), dst.size()};
+    std::array<float, 32> audio{};
+    const buffer_f32_t audio_buffer{audio.data(), audio.size()};
+
+    dsp::decimate::FIRC8xR16x24FS4Decim8 decim_0{};
+    dsp::decimate::FIRC16xR16x32Decim8 decim_1{};
+    dsp::decimate::FIRAndDecimateComplex channel_filter{};
+    dsp::demodulate::FM demod_fm{};
+    AudioOutput audio_output{};
+
+    bool configured{false};
+    uint8_t user_squelch_level{0};
+    FMSquelch fm_squelch{};  // user-adjustable: drives audio muting only
+    FMSquelch carrier_sq{};  // fixed threshold: drives detection gate
+
+    // Audio muting squelch state (user-adjustable level, has hold for smooth audio)
+    bool squelch_is_open{false};
+    uint32_t squelch_hold{0};
+
+    // Carrier-detect gate state (fixed 0.20 threshold, separate from audio squelch)
+    bool carrier_is_open{false};
+    uint32_t carrier_hold{0};
+
+    // CTCSS gate via Goertzel algorithm (per 40 ms window)
+    uint32_t ctcss_freq_x10{0};  // 0 = None → fall back to FMSquelch gate
+    float goertzel_coeff{0.0f};  // 2 * cos(2π * k / WINDOW_SAMPLES)
+    float goertzel_s1{0.0f};
+    float goertzel_s2{0.0f};
+
+    // 40 ms measurement window
+    uint32_t window_sample_count{0};
+    bool was_ctcss_detected{false};
+    uint32_t tone_duration_windows{0};
+
+    // MOTO frequency bank — one Goertzel filter per MOTO table entry.
+    // States reset each window; coefficients set once in configure().
+    float moto_coeff[45]{};
+    float moto_s1[45]{};
+    float moto_s2[45]{};
+
+    ToneDetectDataMessage data_message{};
+    SpectrumCollector channel_spectrum{};
+};
+
+#endif /* __PROC_TONEDETECT_H__ */

firmware/common/message.hpp

@@ -158,6 +158,8 @@ class Message {
         TimeSinkConfig = 100,
         EPIRBTXData = 101,
         P25TxConfigure = 102,
+        ToneDetectData = 103,
+        ToneDetectConfig = 104,
         MAX
     };
 
@@ -1861,4 +1863,25 @@ class NotificationDataMessage : public Message {
     uint16_t timeout = 10000;
 };
 
+// Sent M0→M4: a tone detection event (tone ended, or periodic update while active)
+class ToneDetectDataMessage : public Message {
+   public:
+    constexpr ToneDetectDataMessage()
+        : Message{ID::ToneDetectData} {}
+    uint32_t freq_hz{0};      // Dominant audio frequency in Hz (0 = silence)
+    uint32_t duration_ms{0};  // How long the tone lasted in milliseconds
+    bool tone_end{false};     // True = tone just ended; False = tone still active (periodic update)
+};
+
+// Sent M4→M0: configure the tone detector
+class ToneDetectConfigureMessage : public Message {
+   public:
+    constexpr ToneDetectConfigureMessage(uint8_t squelch = 0, uint32_t ctcss_freq_x10 = 0)
+        : Message{ID::ToneDetectConfig},
+          squelch_level{squelch},
+          ctcss_freq_x10{ctcss_freq_x10} {}
+    uint8_t squelch_level{0};
+    uint32_t ctcss_freq_x10{0};  // CTCSS frequency × 10 (e.g. 1000 = 100.0 Hz); 0 = None
+};
+
 #endif /*__MESSAGE_H__*/

firmware/common/spi_image.hpp

@@ -131,6 +131,7 @@ constexpr image_tag_t image_tag_morse{'P', 'M', 'R', 'S'};
 constexpr image_tag_t image_tag_morsetx{'P', 'M', 'R', 'T'};
 constexpr image_tag_t image_tag_rttyrx{'P', 'R', 'T', 'R'};
 constexpr image_tag_t image_tag_rttytx{'P', 'R', 'T', 'T'};
+constexpr image_tag_t image_tag_tonedetect{'P', 'T', 'N', 'E'};
 
 constexpr image_tag_t image_tag_noop{'P', 'N', 'O', 'P'};
 

firmware/tools/external_app_info.py

@@ -24,4 +24,4 @@
 # external app address ranges below must match those in linker file "external.ld"
 maximum_application_size = 32*1024
 external_apps_address_start = 0xADB00000
-external_apps_address_end = 0xAE020000
+external_apps_address_end = 0xAE060000