POCSAG: decoder fixes, serial output, TX polarity cleanup (#3130)

RX: fix address/batch-boundary handling, add numeric continuation, add heuristic type detection toggle, pass inverted polarity flag, stream decoded messages over USB serial. TX: rename phase to polarity (Standard/Inverted), fix function validation (&&→||), fix serial shell payload read (offset tracking, 31-byte cap, preserve msglen). Decoder: remove color escapes from output (plain text for all consumers), guard count_alpha_fill against empty string, keep numeric_len across continuation batches. Serial format: POCSAG <baud> <addr> <func> <pol> <type> "<msg>" hex:<hex> Quote escaping for embedded " and \\ in alpha messages.
2026-09-08 15:59:08 +00:00 · 2026-04-10 09:35:43 +03:00
parent fc18992442
commit dd006b4830
11 changed files with 549 additions and 92 deletions
@@ -28,6 +28,7 @@
 #include "string_format.hpp"
 #include "utility.hpp"
 #include "file_path.hpp"
+#include "usb_serial_asyncmsg.hpp"

 using namespace portapack;
 using namespace pocsag;
@@ -62,6 +63,7 @@ POCSAGSettingsView::POCSAGSettingsView(
         &check_small_font,
         &check_hide_bad,
         &check_hide_addr_only,
+         &check_numeric_detect,
         &opt_filter_mode,
         &field_filter_address,
         &button_save});
@@ -72,6 +74,7 @@ POCSAGSettingsView::POCSAGSettingsView(
    check_small_font.set_value(settings_.enable_small_font);
    check_hide_bad.set_value(settings_.hide_bad_data);
    check_hide_addr_only.set_value(settings_.hide_addr_only);
+    check_numeric_detect.set_value(settings_.enable_numeric_detect);
    opt_filter_mode.set_by_value(settings_.filter_mode);
    field_filter_address.set_value(settings_.filter_address);

@@ -81,6 +84,7 @@ POCSAGSettingsView::POCSAGSettingsView(
        settings_.enable_small_font = check_small_font.value();
        settings_.hide_bad_data = check_hide_bad.value();
        settings_.hide_addr_only = check_hide_addr_only.value();
+        settings_.enable_numeric_detect = check_numeric_detect.value();
        settings_.filter_mode = opt_filter_mode.selected_index_value();
        settings_.filter_address = field_filter_address.to_integer();
        settings_.baud_rate = opt_baud_rate.selected_index_value();
@@ -219,12 +223,24 @@ void POCSAGAppView::handle_decoded(Timestamp timestamp, const std::string& prefi
        return;
    }

-    // Color indicates the message has a lot of decoding errors.
-    std::string color = bad_data ? STR_COLOR_MAGENTA : STR_COLOR_WHITE;
+    // Type indicator with its own color.
+    std::string type_str;
+    bool numeric_detect = settings_.enable_numeric_detect;
+    if (numeric_detect && pocsag_state.detected == pocsag::DET_NUMERIC)
+        type_str = STR_COLOR_GREEN "n";
+    else if (numeric_detect && pocsag_state.detected == pocsag::DET_ALPHA)
+        type_str = STR_COLOR_LIGHT_GREY "a";
+    else if (pocsag_state.out_type == ADDRESS)
+        type_str = STR_COLOR_DARK_YELLOW "t";
+    else
+        type_str = "";

-    std::string console_info = "\n" + color + prefix;
-    console_info += " #" + to_string_dec_uint(pocsag_state.address);
+    // Header: timestamp+baud in light grey, capcode+function in white.
+    std::string console_info = "\n" STR_COLOR_LIGHT_GREY + prefix;
+    console_info += STR_COLOR_WHITE " #" + to_string_dec_uint(pocsag_state.address);
    console_info += " F" + to_string_dec_uint(pocsag_state.function);
+    if (!type_str.empty())
+        console_info += " " + type_str;

    if (pocsag_state.out_type == ADDRESS) {
        last_address = pocsag_state.address;
@@ -240,23 +256,110 @@ void POCSAGAppView::handle_decoded(Timestamp timestamp, const std::string& prefi
            }
        }

+        /* Serial: tone-only page */
+        if (portapack::usb_serial.serial_connected()) {
+            std::string s = "\r\nPOCSAG " + to_string_dec_uint(current_bitrate) + " " + to_string_dec_uint(pocsag_state.address) + " " + std::string(1, 'A' + pocsag_state.function) + (current_inverted ? " I" : " S") + " tone";
+            UsbSerialAsyncmsg::asyncmsg(s);
+        }
+
    } else if (pocsag_state.out_type == MESSAGE) {
-        if (pocsag_state.address != last_address) {
-            // New message
+        if (pocsag_state.new_message) {
            last_address = pocsag_state.address;
+            serial_numeric_sent = 0;
            console.writeln(console_info);
-            console.write(color + pocsag_state.output);
+
+            // If heuristic chose numeric, show numeric line first (green).
+            if (numeric_detect &&
+                pocsag_state.detected == pocsag::DET_NUMERIC &&
+                pocsag_state.numeric_len > 0) {
+                std::string num_str(pocsag_state.numeric_buf, pocsag_state.numeric_len);
+                console.write(STR_COLOR_GREEN + num_str);
+                console.writeln("");
+            }
+
+            // Alpha decode (already has per-char color escapes from decoder).
+            console.write(pocsag_state.output);
+
+            /* Serial: header + first chunk.
+             * hex field contains rendered alpha as hex bytes (color escapes
+             * stripped).  Non-printable and uncorrectable chars show as '.'
+             * (0x2E) — original 7-bit values are not preserved.
+             * Numeric decode goes in the quoted message field only. */
+            if (portapack::usb_serial.serial_connected()) {
+                /* Build hex representation of decoded alpha characters. */
+                std::string raw;
+                for (size_t i = 0; i < pocsag_state.output.size(); ++i)
+                    raw += to_string_hex((uint8_t)pocsag_state.output[i], 2);
+
+                std::string s = "\r\nPOCSAG " + to_string_dec_uint(current_bitrate) + " " + to_string_dec_uint(pocsag_state.address) + " " + std::string(1, 'A' + pocsag_state.function) + (current_inverted ? " I" : " S");
+
+                if (numeric_detect && pocsag_state.detected == pocsag::DET_NUMERIC) {
+                    s += " numeric \"";
+                    if (pocsag_state.numeric_len > 0)
+                        s += std::string(pocsag_state.numeric_buf, pocsag_state.numeric_len);
+                    s += "\"";
+                    serial_numeric_sent = pocsag_state.numeric_len;
+                } else {
+                    /* For alpha, the quoted text is the same chars as raw but as ASCII.
+                     * Escape " and \ to avoid breaking the quoted field. */
+                    s += " alpha \"";
+                    for (size_t i = 0; i < pocsag_state.output.size(); ++i) {
+                        if (pocsag_state.output[i] == '"' || pocsag_state.output[i] == '\\') {
+                            s += '\\';
+                        }
+                        s += pocsag_state.output[i];
+                    }
+                    s += "\"";
+                }
+                s += " hex:" + raw;
+                UsbSerialAsyncmsg::asyncmsg(s);
+            }
        } else {
-            // Message continues...
-            console.write(color + pocsag_state.output);
+            // Message continues from previous batch.
+            bool is_numeric = numeric_detect && pocsag_state.detected == pocsag::DET_NUMERIC;
+
+            // GUI: show numeric continuation if applicable.
+            if (is_numeric && pocsag_state.numeric_len > serial_numeric_sent) {
+                std::string num_str(pocsag_state.numeric_buf + serial_numeric_sent,
+                                    pocsag_state.numeric_len - serial_numeric_sent);
+                console.write(STR_COLOR_GREEN + num_str);
+            }
+            console.write(pocsag_state.output);
+
+            /* Serial: continuation chunk with full header.
+             * Type label carries over from first batch (numeric+ or alpha+). */
+            if (portapack::usb_serial.serial_connected()) {
+                std::string raw;
+                std::string decoded;
+                for (size_t i = 0; i < pocsag_state.output.size(); ++i) {
+                    if (pocsag_state.output[i] == '"' || pocsag_state.output[i] == '\\')
+                        decoded += '\\';
+                    decoded += pocsag_state.output[i];
+                    raw += to_string_hex((uint8_t)pocsag_state.output[i], 2);
+                }
+                if (!decoded.empty() || pocsag_state.numeric_len > serial_numeric_sent) {
+                    std::string s = "\r\nPOCSAG " + to_string_dec_uint(current_bitrate) + " " + to_string_dec_uint(pocsag_state.address) + " " + std::string(1, 'A' + pocsag_state.function) + (current_inverted ? " I" : " S") + (is_numeric ? " numeric+" : " alpha+") + " \"";
+                    if (is_numeric && pocsag_state.numeric_len > serial_numeric_sent)
+                        s += std::string(pocsag_state.numeric_buf + serial_numeric_sent,
+                                         pocsag_state.numeric_len - serial_numeric_sent);
+                    else
+                        s += decoded;
+                    s += "\" hex:" + raw;
+                    UsbSerialAsyncmsg::asyncmsg(s);
+                }
+            }
+            serial_numeric_sent = pocsag_state.numeric_len;
        }

        if (logging()) {
-            logger.log_decoded(
-                timestamp,
-                to_string_dec_uint(pocsag_state.address) +
-                    " F" + to_string_dec_uint(pocsag_state.function) +
-                    " " + pocsag_state.output);
+            std::string log_entry = to_string_dec_uint(pocsag_state.address) +
+                                    " F" + to_string_dec_uint(pocsag_state.function);
+            if (numeric_detect &&
+                pocsag_state.detected == pocsag::DET_NUMERIC &&
+                pocsag_state.numeric_len > 0)
+                log_entry += " N:" + std::string(pocsag_state.numeric_buf, pocsag_state.numeric_len);
+            log_entry += " " + pocsag_state.output;
+            logger.log_decoded(timestamp, log_entry);
        }
    }
 }
@@ -300,13 +403,19 @@ void POCSAGAppView::on_packet(const POCSAGPacketMessage* message) {
        image_status.set_foreground(Theme::getInstance()->fg_magenta->foreground);
        pocsag_state.codeword_index = 0;
        pocsag_state.errors = 0;
+        current_bitrate = message->packet.bitrate();
+        current_inverted = message->packet.inverted();

        // Handle multiple messages (if any).
        while (pocsag_decode_batch(message->packet, pocsag_state))
            handle_decoded(message->packet.timestamp(), prefix);

-        // Handle the remainder.
-        handle_decoded(message->packet.timestamp(), prefix);
+        // Handle the remainder. Skip if decoder is still in
+        // STATE_HAVE_ADDRESS — the address was at the end of this
+        // batch and we can't yet tell if it's tone-only or has
+        // message data in the next batch.
+        if (pocsag_state.mode != STATE_HAVE_ADDRESS)
+            handle_decoded(message->packet.timestamp(), prefix);
    }

    // Set status icon color to indicate state machine state.
@@ -125,6 +125,7 @@ struct POCSAGSettings {
    bool enable_raw_log = false;
    bool hide_bad_data = false;
    bool hide_addr_only = false;
+    bool enable_numeric_detect = true; /* heuristic alpha/numeric type detection */
    uint8_t filter_mode = false;
    int32_t baud_rate = -1;
    uint32_t filter_address = 0;
@@ -150,8 +151,8 @@ class POCSAGSettingsView : public View {

    Labels labels{
        {{2 * 8, 0 * 16}, "Baud:", Theme::getInstance()->fg_light->foreground},
-        {{2 * 8, 12 * 16}, "Filter Mode:", Theme::getInstance()->fg_light->foreground},
-        {{2 * 8, 13 * 16}, "Filter Addr:", Theme::getInstance()->fg_light->foreground},
+        {{2 * 8, 14 * 16}, "Filter Mode:", Theme::getInstance()->fg_light->foreground},
+        {{2 * 8, 15 * 16}, "Filter Addr:", Theme::getInstance()->fg_light->foreground},
    };

    Checkbox check_log{
@@ -179,21 +180,26 @@ class POCSAGSettingsView : public View {
        22,
        "Hide Addr Only"};

+    Checkbox check_numeric_detect{
+        {2 * 8, 12 * 16},
+        22,
+        "Detect Numeric"};
+
    OptionsField opt_filter_mode{
-        {15 * 8, 12 * 16},
+        {15 * 8, 14 * 16},
        4,
        {{"None", FILTER_NONE},
         {"Drop", FILTER_DROP},
         {"Keep", FILTER_KEEP}}};

    SymField field_filter_address{
-        {15 * 8, 13 * 16},
+        {15 * 8, 15 * 16},
        7,
        SymField::Type::Dec,
        true /*explicit_edit*/};

    Button button_save{
-        {UI_POS_X_CENTER(10), UI_POS_Y(16), 10 * 8, 2 * 16},
+        {UI_POS_X_CENTER(10), UI_POS_Y(17), 10 * 8, 2 * 16},
        "Save"};
 };

@@ -231,6 +237,7 @@ class POCSAGAppView : public View {
            {"filter_address"sv, &settings_.filter_address},
            {"hide_bad_data"sv, &settings_.hide_bad_data},
            {"hide_addr_only"sv, &settings_.hide_addr_only},
+            {"numeric_detect"sv, &settings_.enable_numeric_detect},
            {"baud_rate"sv, &settings_.baud_rate},
        }};

@@ -241,6 +248,10 @@ class POCSAGAppView : public View {
    void on_stats(const POCSAGStatsMessage* stats);

    uint32_t last_address = 0;
+    uint16_t current_bitrate = 0;    /* bitrate of current packet being decoded */
+    bool current_inverted = false;   /* polarity of current packet being decoded */
+    uint8_t serial_numeric_sent = 0; /* numeric chars already sent to serial/GUI */
+
    pocsag::EccContainer ecc{};
    pocsag::POCSAGState pocsag_state{&ecc};
    POCSAGLogger logger{};
@@ -56,7 +56,8 @@ void POCSAGTXView::on_remete(const PocsagTosendMessage data) {
    if (data.function == 'C') tmp = 2;
    if (data.function == 'D') tmp = 3;
    options_function.set_selected_index(tmp);
-    options_phase.set_selected_index(data.phase == 'P' ? 0 : 1);
+    /* 'S' = Standard (CCIR Rec. 584 polarity), 'I' = Inverted */
+    options_polarity.set_selected_index(data.polarity == 'S' ? 0 : 1);
    field_address.set_value(data.addr);
    message = (char*)data.msg;
    buffer = message;
@@ -64,7 +65,7 @@ void POCSAGTXView::on_remete(const PocsagTosendMessage data) {
    options_bitrate.dirty();
    options_type.dirty();
    options_function.dirty();
-    options_phase.dirty();
+    options_polarity.dirty();
    field_address.dirty();
    text_message.dirty();
    tx_view.focus();
@@ -100,7 +101,17 @@ bool POCSAGTXView::start_tx() {
            return false;
        }
    }
-    MessageType phase = (MessageType)options_phase.selected_index_value();
+    /*
+     * TX polarity inversion (CCIR Rec. 584):
+     *
+     * The FSK modulator (proc_fsk.cpp) maps bit 1 to positive deviation.
+     * Standard POCSAG requires bit 1 to negative deviation.
+     *
+     * "Standard" (value 0): invert codewords so that original bit 1 becomes
+     *   bit 0 in the modulator, producing negative deviation. This is the standard.
+     * "Inverted" (value 1): send codewords as-is. Bit 1 produces positive deviation.
+     */
+    bool invert_polarity = (options_polarity.selected_index_value() == 0);

    pocsag_encode(type, BCH_code, options_function.selected_index_value(), message, address, codewords);

@@ -118,10 +129,7 @@ bool POCSAGTXView::start_tx() {

    bi = 0;
    for (i = 0; i < codewords.size(); i++) {
-        if (phase == 0)
-            codeword = ~(codewords[i]);
-        else
-            codeword = codewords[i];
+        codeword = invert_polarity ? ~(codewords[i]) : codewords[i];

        data_ptr[bi++] = (codeword >> 24) & 0xFF;
        data_ptr[bi++] = (codeword >> 16) & 0xFF;
@@ -166,15 +174,17 @@ POCSAGTXView::POCSAGTXView(
                  &field_address,
                  &options_type,
                  &options_function,
-                  &options_phase,
+                  &options_polarity,
                  &text_message,
                  &text_message_l2,
                  &button_message,
                  &progressbar,
                  &tx_view});

-    options_bitrate.set_selected_index(1);  // 1200bps
-    options_type.set_selected_index(0);     // Address only
+    options_bitrate.set_selected_index(1);   // 1200 bps
+    options_type.set_selected_index(2);      // Alphanumeric
+    options_function.set_selected_index(0);  // Function A
+    options_polarity.set_selected_index(0);  // Standard (CCIR Rec. 584)

    field_address.set_value(persistent_memory::pocsag_last_address());

@@ -84,7 +84,7 @@ class POCSAGTXView : public View {
        {{3 * 8, 6 * 8}, "Address:", Theme::getInstance()->fg_light->foreground},
        {{6 * 8, 8 * 8}, "Type:", Theme::getInstance()->fg_light->foreground},
        {{2 * 8, 10 * 8}, "Function:", Theme::getInstance()->fg_light->foreground},
-        {{5 * 8, 12 * 8}, "Phase:", Theme::getInstance()->fg_light->foreground},
+        {{2 * 8, 12 * 8}, "Polarity:", Theme::getInstance()->fg_light->foreground},
        {{UI_POS_X(0), 14 * 8}, "Message:", Theme::getInstance()->fg_light->foreground}};

    OptionsField options_bitrate{
@@ -113,12 +113,20 @@ class POCSAGTXView : public View {
         {"C", 2},
         {"D", 3}}};

-    OptionsField options_phase{
+    /*
+     * TX polarity (CCIR Rec. 584):
+     *   "Standard" (value 0): bit 1 = negative deviation (CCIR Rec. 584 standard).
+     *              Codewords are bitwise-inverted before the FSK modulator
+     *              because the modulator maps bit 1 to positive deviation.
+     *   "Inverted" (value 1): bit 1 = positive deviation (non-standard).
+     *              Codewords are sent as-is to the modulator.
+     */
+    OptionsField options_polarity{
        {11 * 8, 12 * 8},
-        1,
+        8,
        {
-            {"P", 0},
-            {"N", 1},
+            {"Standard", 0},
+            {"Inverted", 1},
        }};

    Text text_message{
@@ -1262,7 +1262,7 @@ static void cmd_settingsreset(BaseSequentialStream* chp, int argc, char* argv[])
 }

 static void cmd_sendpocsag(BaseSequentialStream* chp, int argc, char* argv[]) {
-    const char* usage = "usage: sendpocsag <addr> <msglen> [baud] [type] [function] [phase] \r\n";
+    const char* usage = "usage: sendpocsag <addr> <msglen> [baud] [type] [function] [polarity:S|I] \r\n";
    (void)argv;
    if (argc < 2) {
        chprintf(chp, usage);
@@ -1293,34 +1293,48 @@ static void cmd_sendpocsag(BaseSequentialStream* chp, int argc, char* argv[]) {
        }
    }

-    char function = 'D';
+    char function = 'A';
    if (argc >= 5) {
        function = *argv[4];
-        if (function < 'A' && function > 'D') {
+        if (function < 'A' || function > 'D') {
            chprintf(chp, "error, function can be A, B, C or D\r\n");
            return;
        }
    }

-    char phase = 'P';
+    char polarity = 'S'; /* Standard = CCIR Rec. 584 (bit 1 = negative deviation) */
    if (argc >= 6) {
-        phase = *argv[5];
-        if (phase != 'P' && phase != 'N') {
-            chprintf(chp, "error, phase can be P or N\r\n");
+        polarity = *argv[5];
+        /*
+         * Legacy compatibility: old firmware used 'P'/'N' with opposite semantics.
+         *   Old 'P' (phase=positive) = inverted codewords = standard POCSAG = new 'S' (Standard)
+         *   Old 'N' (phase=negative) = no inversion = inverted POCSAG = new 'I' (Inverted)
+         * New firmware uses 'S'/'I':
+         *   'S' = Standard (CCIR Rec. 584, bit 1 = negative deviation)
+         *   'I' = Inverted (bit 1 = positive deviation)
+         */
+        if (polarity == 'P') polarity = 'S'; /* legacy 'P' maps to Standard */
+        if (polarity == 'N') polarity = 'I'; /* legacy 'N' maps to Inverted */
+        if (polarity != 'S' && polarity != 'I') {
+            chprintf(chp, "error, polarity can be S (Standard) or I (Inverted)\r\n");
            return;
        }
    }

-    uint8_t msg[81] = {0};
-    if (msglen > 0) {
-        chprintf(chp, "send %d bytes\r\n", msglen);
-        do {
-            size_t bytes_to_read = msglen > USB_BULK_BUFFER_SIZE ? USB_BULK_BUFFER_SIZE : msglen;
-            size_t bytes_read = chSequentialStreamRead(chp, &msg[0], bytes_to_read);
+    uint8_t msg[31] = {0};
+    uint8_t original_msglen = (msglen > 31) ? 31 : msglen;
+    if (original_msglen > 0) {
+        chprintf(chp, "send %d bytes\r\n", original_msglen);
+        size_t offset = 0;
+        size_t remaining = original_msglen;
+        while (remaining > 0) {
+            size_t bytes_to_read = remaining > USB_BULK_BUFFER_SIZE ? USB_BULK_BUFFER_SIZE : remaining;
+            size_t bytes_read = chSequentialStreamRead(chp, &msg[offset], bytes_to_read);
            if (bytes_read != bytes_to_read)
                return;
-            msglen -= bytes_read;
-        } while (msglen > 0);
+            offset += bytes_read;
+            remaining -= bytes_read;
+        }
    }

    auto evtd = getEventDispatcherInstance();
@@ -1334,7 +1348,7 @@ static void cmd_sendpocsag(BaseSequentialStream* chp, int argc, char* argv[]) {
        return;
    }
    chThdSleepMilliseconds(1000);  // wait for app to start
-    PocsagTosendMessage message{(uint16_t)baud, (uint8_t)type, function, phase, (uint8_t)msglen, msg, addr};
+    PocsagTosendMessage message{(uint16_t)baud, (uint8_t)type, function, polarity, original_msglen, msg, addr};
    EventDispatcher::send_message(message);
    chprintf(chp, "ok\r\n");
 }