di 1 incre

main.cpp

@@ -511,8 +511,9 @@ void print_help(const char* exe_name) {
         << "  do1_toggle_per_frame -> hardware cyclic DO1 pattern in module memory:\n"
         << "                         DO1 outputs 00110011... continuously (toggle every 2 ADC ticks)\n"
         << "                         without per-tick DOUT updates from PC\n"
-        << "  do1_noise_subtract -> with tty + do1_toggle_per_frame, use programmed DO1 phase (0011...)\n"
+        << "  do1_noise_subtract -> with tty + do1_toggle_per_frame, use DI1 state from synchronous DIN\n"
-        << "                        to average recent noise steps and subtract it from useful steps before tty output\n"
+        << "                        (expected DO1->DI1 loopback) to average recent noise steps and subtract it\n"
+        << "                        from useful steps before tty output\n"
         << "                        (only corrected DO1=LOW steps are sent to tty)\n"
         << "  noise_avg_steps:N -> number of recent DO1=HIGH noise steps per channel used as subtraction baseline\n"
         << "                       (required when do1_noise_subtract is enabled)\n"
@@ -543,8 +544,8 @@ void print_help(const char* exe_name) {
         << "The live HTML supports X/Y zoom buttons, mouse-wheel zoom, and reset.\n"
         << "For tty output, use di1_group_avg together with di1:trace to emit one averaged 4-word step\n"
         << "per constant DI1 run while keeping the current ring-buffered binary frame format.\n"
-        << "For DO1-phase subtraction, use do1_toggle_per_frame + do1_noise_subtract + noise_avg_steps:N;\n"
+        << "For DO1 subtraction with loopback, use do1_toggle_per_frame + do1_noise_subtract + noise_avg_steps:N;\n"
-        << "the first ADC sample in each packet is treated as DO1 LOW in the 0011... sequence.\n"
+        << "DI1 from synchronous DIN is used as the actual DO1 state marker.\n"
         << "Amplitude mode keeps the raw AD8317 voltage as captured on X1; no inversion is applied.\n"
         << "\n"
         << "Phase profile example:\n"
@@ -1238,8 +1239,8 @@ struct Do1NoiseSubtractState {
     std::array<double, 2> noise_ring_sum {};
     std::array<double, 2> step_sum {};
     std::array<uint32_t, 2> step_count {};
-    uint32_t ticks_in_step = 0;
+    bool step_level_initialized = false;
-    bool step_do1_high = false;
+    bool step_di1_high = false;
     uint16_t next_index = 1;
 
     void configure(uint32_t history_steps) {
@@ -1253,18 +1254,24 @@ struct Do1NoiseSubtractState {
     void clear_step() {
         step_sum = {};
         step_count = {};
-        ticks_in_step = 0;
     }
 
     void reset_packet() {
         clear_step();
-        step_do1_high = false;
+        step_level_initialized = false;
+        step_di1_high = false;
         next_index = 1;
         noise_ring_head = {};
         noise_ring_size = {};
         noise_ring_sum = {};
     }
 
+    void start_new_step(bool di1_high) {
+        clear_step();
+        step_di1_high = di1_high;
+        step_level_initialized = true;
+    }
+
     void add_sample(uint32_t lch, double raw_code) {
         if (lch >= step_sum.size()) {
             return;
@@ -1273,15 +1280,6 @@ struct Do1NoiseSubtractState {
         ++step_count[lch];
     }
 
-    bool advance_tick() {
-        ++ticks_in_step;
-        if (ticks_in_step < kDo1TogglePeriodTicks) {
-            return false;
-        }
-        ticks_in_step = 0;
-        return true;
-    }
-
     bool has_complete_step(uint32_t channel_count) const {
         return (step_count[0] != 0U) && ((channel_count <= 1U) || (step_count[1] != 0U));
     }
@@ -1327,11 +1325,7 @@ struct Do1NoiseSubtractState {
         return noise_ring_sum[lch] / static_cast<double>(size);
     }
 
-    void finish_step() {
+    void finish_step() { clear_step(); }
-        step_do1_high = !step_do1_high;
-        step_sum = {};
-        step_count = {};
-    }
 };
 
 int16_t pack_raw_code_to_int16(double avg_raw_code) {
@@ -1650,6 +1644,8 @@ int run(const Config& cfg) {
                   << "  input buffer words: " << cfg.input_buffer_words << "\n"
                   << "  tty di1_group_avg: " << (tty_di1_group_average ? "enabled" : "disabled") << "\n"
                   << "  tty do1_noise_subtract: " << (tty_do1_noise_subtract ? "enabled" : "disabled") << "\n"
+                  << "  do1_noise_subtract marker: "
+                  << (tty_do1_noise_subtract ? "DI1 from DIN (DO1->DI1 loopback expected)" : "n/a") << "\n"
                   << "  noise_avg_steps: "
                   << (tty_do1_noise_subtract ? std::to_string(*cfg.noise_avg_steps) : std::string("n/a")) << "\n"
                   << "  stream-only note: ignoring csv/svg/live_html/live_json/live_update_period_ms/svg_history_packets\n";
@@ -1876,6 +1872,10 @@ int run(const Config& cfg) {
             return;
         }
 
+        if (!tty_do1_noise_state.step_level_initialized) {
+            return;
+        }
+
         if (!tty_do1_noise_state.has_complete_step(cfg.channel_count)) {
             tty_do1_noise_state.finish_step();
             return;
@@ -1884,7 +1884,7 @@ int run(const Config& cfg) {
         const double ch1_avg = tty_do1_noise_state.step_average(0U);
         const double ch2_avg = (cfg.channel_count <= 1U) ? 0.0 : tty_do1_noise_state.step_average(1U);
 
-        if (tty_do1_noise_state.step_do1_high) {
+        if (tty_do1_noise_state.step_di1_high) {
             tty_do1_noise_state.push_noise_average(0U, ch1_avg);
             if (cfg.channel_count > 1U) {
                 tty_do1_noise_state.push_noise_average(1U, ch2_avg);
@@ -1960,7 +1960,8 @@ int run(const Config& cfg) {
             append_tty_group_step();
             tty_group_state.clear_step();
         } else if (tty_do1_noise_subtract) {
-            // Keep only complete programmed DO1 steps. Partial steps are dropped on packet close.
+            // Finalize the last DI1 run in packet, drop only incomplete channel tuples.
+            append_tty_do1_subtracted_step();
             tty_do1_noise_state.clear_step();
         }
 
@@ -2343,6 +2344,13 @@ int run(const Config& cfg) {
             if (tty_di1_group_average && di1_changed) {
                 append_tty_group_step();
                 tty_group_state.clear_step();
+            } else if (tty_do1_noise_subtract) {
+                if (!tty_do1_noise_state.step_level_initialized) {
+                    tty_do1_noise_state.start_new_step(di1_level);
+                } else if (di1_changed) {
+                    append_tty_do1_subtracted_step();
+                    tty_do1_noise_state.start_new_step(di1_level);
+                }
             }
 
             if (!fast_tty_avg_stream_mode &&
@@ -2356,9 +2364,6 @@ int run(const Config& cfg) {
                 if (fast_packet_frames < target_frames) {
                     if (tty_do1_noise_subtract) {
                         tty_do1_noise_state.add_sample(lch, adc_raw_value);
-                        if (tty_do1_noise_state.advance_tick()) {
-                            append_tty_do1_subtracted_step();
-                        }
                     } else {
                         tty_group_state.add_sample(lch, adc_raw_value);
                     }