минор фиксы pcb

Пины и ШИМ для S3 (не проверено)
Добавлена разведенная PCB плата
2026-08-08 20:02:14 +03:00 · 2026-08-08 19:50:34 +03:00 · 2026-08-08 19:49:35 +03:00 · 2026-08-08 11:15:20 +03:00 · 2026-08-08 10:42:59 +03:00 · 2026-08-08 10:18:50 +03:00
40 changed files with 2254 additions and 219 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -1 +1,7 @@
 /tests/
+/PCB/Project Logs*/
+/*/__Previews
+/*/History
+/*/Project Logs*/
+
+
--- a/OpticalChannelTester/App.cpp
+++ b/OpticalChannelTester/App.cpp
@@ -1,9 +1,13 @@
 #include "App.h"
 #include "Config.h"
+#include "Config_Text.h"
 #include "Log.h"
 #include <WiFi.h>
 #include <esp_mac.h>
+#include <esp_sleep.h>
 #include <esp_system.h>
+#include <esp32-hal-cpu.h>
+#include <driver/gpio.h>
 #include <math.h>
 #include <string.h>

@@ -26,6 +30,51 @@ void formatErrorDuty(float duty, char *out, size_t size) {
  if (fabsf(duty - roundf(duty)) < 0.05f) snprintf(out, size, "%.0f%%", duty);
  else snprintf(out, size, "%.1f%%", duty);
 }
+
+size_t utf8CharacterCount(const char *text) {
+  size_t count = 0;
+  while (text && *text) {
+    const uint8_t byte = static_cast<uint8_t>(*text++);
+    // Continuation bytes (10xxxxxx) belong to the preceding UTF-8 character.
+    if ((byte & 0xC0U) != 0x80U) ++count;
+  }
+  return count;
+}
+
+const char *uiRoleName(Role role) {
+  const uint8_t index = static_cast<uint8_t>(role);
+  return index < sizeof(UiText::ROLE_NAMES) / sizeof(UiText::ROLE_NAMES[0])
+    ? UiText::ROLE_NAMES[index] : "?";
+}
+
+const char *uiFailName(FailReason reason) {
+  const uint8_t index = static_cast<uint8_t>(reason);
+  return index < sizeof(UiText::FAIL_NAMES) / sizeof(UiText::FAIL_NAMES[0])
+    ? UiText::FAIL_NAMES[index] : "UNKNOWN";
+}
+
+void formatMenuLine(const char *label, const char *value, char *out, size_t size) {
+  constexpr size_t OLED_TEXT_COLUMNS = 21;
+  const size_t labelLength = utf8CharacterCount(label);
+  const size_t valueLength = utf8CharacterCount(value);
+  const size_t usedColumns = labelLength + valueLength;
+  const int padding = static_cast<int>(
+    usedColumns < OLED_TEXT_COLUMNS ? OLED_TEXT_COLUMNS - usedColumns : 0U);
+  snprintf(out, size, "%s%*s%s", label, padding, "", value);
+}
+
+uint32_t overallProgress(uint32_t stageIndex, uint8_t step) {
+  if (step > MEASUREMENT_PROGRESS_STEPS) step = MEASUREMENT_PROGRESS_STEPS;
+  return stageIndex * MEASUREMENT_PROGRESS_STEPS + step;
+}
+
+uint32_t overallProgressTotal(uint32_t stageCount) {
+  return stageCount * MEASUREMENT_PROGRESS_STEPS;
+}
+
+uint32_t stageWallTimeMs(uint32_t testTimeMs, uint32_t frequencyHz) {
+  return static_cast<uint32_t>((nominalStageUs(frequencyHz, testTimeMs, PWM_SETTLE_CYCLES) + 999ULL) / 1000ULL);
+}
 }

 App::App() : startButton_(GPIO_BUTTON_START), modeButton_(GPIO_BUTTON_MODE), measurement_(receiver_) {}
@@ -53,12 +102,15 @@ void App::finishInitialization(bool factoryReset) {
  initialized_ = true;
  if (!receiver_.begin()) { Log::event("BOOT", "FATAL: capture peripheral init failed"); finish(false, FailReason::UNSUPPORTED); return; }
  Log::printf("BOOT", "capture initialized: %s", receiver_.highRateBackend() ? "RMT DMA" : "RMT ping-pong");
+  lastUserActivityMs_ = millis();
+  setActivePerformance(false);
  printConfiguration();
  if (static_cast<Role>(settings_.role) == Role::SLAVE) armSlave();
  else showIdle();
 }

 void App::update() {
+  serviceIdlePowerSave();
  const uint32_t now = millis();
  const ButtonEvent startEvent = startButton_.update(now);
  const ButtonEvent modeEvent = modeButton_.update(now);
@@ -66,6 +118,10 @@ void App::update() {
    Log::printf("INPUT", "START %s state=%s", buttonEventName(startEvent), appStateName(state_));
  if (modeEvent != ButtonEvent::NONE)
    Log::printf("INPUT", "MODE %s state=%s", buttonEventName(modeEvent), appStateName(state_));
+  if (startEvent != ButtonEvent::NONE || modeEvent != ButtonEvent::NONE) {
+    lastUserActivityMs_ = now;
+    leaveIdlePowerSave();
+  }
  if (!initialized_) {
    if (!startButton_.pressed() || !modeButton_.pressed()) finishInitialization(false);
    else if (now - bootCheckStartedMs_ >= FACTORY_RESET_HOLD_MS) finishInitialization(true);
@@ -103,7 +159,7 @@ void App::update() {
  }
  if (state_ == AppState::MENU) {
    if (modeEvent == ButtonEvent::SHORT) {
-      menuItem_ = (menuItem_ + 1U) % 7U; Log::printf("ACTION", "menu item selected index=%u", menuItem_); showMenu();
+      menuItem_ = (menuItem_ + 1U) % 5U; Log::printf("ACTION", "menu item selected index=%u", menuItem_); showMenu();
    }
    else if (modeEvent == ButtonEvent::LONG) {
      sanitizeRange(); const bool saved = store_.save(settings_); params_ = store_.params(settings_);
@@ -140,29 +196,26 @@ void App::update() {
 }

 void App::showIdle() {
-  char one[24]; snprintf(one, sizeof(one), "MODE: %s", roleName(static_cast<Role>(settings_.role)));
-  display_.show(one, "START=RUN");
+  setActivePerformance(false);
+  lastUserActivityMs_ = millis();
+  char one[64]; snprintf(one, sizeof(one), "%s%s", UiText::MODE_PREFIX,
+    uiRoleName(static_cast<Role>(settings_.role)));
+  display_.show(one, UiText::START_RUN);
 }

 void App::sanitizeRange() {
-  settings_.startIndex %= countOf(START_FREQ_OPTIONS_HZ); settings_.endIndex %= countOf(END_FREQ_OPTIONS_HZ);
-  if (END_FREQ_OPTIONS_HZ[settings_.endIndex] <= START_FREQ_OPTIONS_HZ[settings_.startIndex]) {
-    size_t i = 0;
-    while (i < countOf(END_FREQ_OPTIONS_HZ) && END_FREQ_OPTIONS_HZ[i] <= START_FREQ_OPTIONS_HZ[settings_.startIndex]) ++i;
-    if (i == countOf(END_FREQ_OPTIONS_HZ)) { settings_.startIndex = 0; i = countOf(END_FREQ_OPTIONS_HZ) - 1; }
-    settings_.endIndex = i;
-  }
+  settings_.startIndex %= countOf(START_FREQ_OPTIONS_HZ);
+  settings_.endIndex %= countOf(END_FREQ_OPTIONS_HZ);
 }

 void App::changeMenu(int d) {
+  sanitizeRange();
  uint8_t *value = nullptr; size_t count = 0;
  switch (menuItem_) {
    case 0: value = &settings_.startIndex; count = countOf(START_FREQ_OPTIONS_HZ); break;
    case 1: value = &settings_.endIndex; count = countOf(END_FREQ_OPTIONS_HZ); break;
-    case 2: value = &settings_.stepIndex; count = countOf(STEP_OPTIONS_HZ); break;
-    case 3: value = &settings_.accuracyIndex; count = countOf(ACCURACY_OPTIONS_PCT); break;
-    case 4: value = &settings_.timeIndex; count = countOf(TEST_TIME_OPTIONS_MS); break;
-    case 5: value = &settings_.repeatIndex; count = countOf(REPEAT_OPTIONS); break;
+    case 2: value = &settings_.accuracyIndex; count = countOf(ACCURACY_OPTIONS_PCT); break;
+    case 3: value = &settings_.timeIndex; count = countOf(TEST_TIME_OPTIONS_MS); break;
    default: value = &settings_.dutyIndex; count = countOf(DUTY_OPTIONS_PCT); break;
  }
  *value = static_cast<uint8_t>((*value + count + d) % count);
@@ -171,34 +224,53 @@ void App::changeMenu(int d) {
 }

 void App::showMenu() {
-  char one[22], two[22], all[12];
+  char one[64], value[24], total[64], all[12];
+  const char *label = nullptr;
  Display::formatDuration(actualNominalTotalUs(), all, sizeof(all));
  switch (menuItem_) {
-    case 0: snprintf(one, sizeof(one), "START FREQ"); Display::formatFrequency(params_.startHz, two, sizeof(two)); break;
-    case 1: snprintf(one, sizeof(one), "END FREQ"); Display::formatFrequency(params_.endHz, two, sizeof(two)); break;
-    case 2: snprintf(one, sizeof(one), "FREQ STEP"); Display::formatFrequency(params_.stepHz, two, sizeof(two)); break;
-    case 3: snprintf(one, sizeof(one), "ACCURACY"); snprintf(two, sizeof(two), "+/-%g%%", params_.accuracyPct); break;
-    case 4: snprintf(one, sizeof(one), "TEST TIME"); snprintf(two, sizeof(two), "%.1fs", params_.testTimeMs / 1000.0f); break;
-    case 5: snprintf(one, sizeof(one), "REPEATS"); snprintf(two, sizeof(two), "%ux", params_.repeats); break;
-    default: snprintf(one, sizeof(one), "PWM DUTY"); snprintf(two, sizeof(two), "%u%%", params_.dutyPct); break;
+    case 0:
+      Display::formatTestFrequency(params_.startHz, value, sizeof(value));
+      strncat(value, UiText::FREQUENCY_UNIT, sizeof(value) - strlen(value) - 1U);
+      label = UiText::MENU_START_FREQUENCY;
+      break;
+    case 1:
+      Display::formatTestFrequency(params_.endHz, value, sizeof(value));
+      strncat(value, UiText::FREQUENCY_UNIT, sizeof(value) - strlen(value) - 1U);
+      label = UiText::MENU_END_FREQUENCY;
+      break;
+    case 2:
+      snprintf(value, sizeof(value), "+/-%g%%", params_.accuracyPct);
+      label = UiText::MENU_ACCURACY;
+      break;
+    case 3:
+      snprintf(value, sizeof(value), "%.1fs", params_.testTimeMs / 1000.0f);
+      label = UiText::MENU_TEST_TIME;
+      break;
+    default:
+      snprintf(value, sizeof(value), "%u%%", params_.dutyPct);
+      label = UiText::MENU_PWM_DUTY;
+      break;
  }
-  const size_t used = strlen(two); snprintf(two + used, sizeof(two) - used, " ALL %s", all); display_.show(one, two);
+  formatMenuLine(label, value, one, sizeof(one));
+  formatMenuLine(UiText::MENU_TOTAL_TIME, all, total, sizeof(total));
+  display_.show(one, total);
 }

 void App::startTest() {
-  params_ = store_.params(settings_); stageCount_ = frequencyPointCount(params_.startHz, params_.endHz, params_.stepHz);
+  leaveIdlePowerSave();
+  setActivePerformance(true);
+  params_ = store_.params(settings_); stageCount_ = frequencyPointCount(params_.startHz, params_.endHz);
  stageIndex_ = 0; requestedHz_ = 0; pendingReason_ = FailReason::NONE;
  havePeer_ = false; lastHeartbeatMs_ = 0; lastPeerSeenMs_ = 0;
  if (!stageCount_) { finish(false, FailReason::UNSUPPORTED); return; }
  Log::printf("TEST", "starting role=%s stages=%lu", roleName(static_cast<Role>(settings_.role)), stageCount_);
  if (SERIAL_MINIMAL_LOG) {
-    char startText[12], endText[12], stepText[12];
+    char startText[12], endText[12];
    Display::formatFrequency(params_.startHz, startText, sizeof(startText));
    Display::formatFrequency(params_.endHz, endText, sizeof(endText));
-    Display::formatFrequency(params_.stepHz, stepText, sizeof(stepText));
-    Log::printf("CONFIG", "mode=%s range=%s..%s step=%s accuracy=%.2f%% time=%lums repeats=%u duty=%u%% stages=%lu",
-      roleName(static_cast<Role>(settings_.role)), startText, endText, stepText,
-      params_.accuracyPct, params_.testTimeMs, params_.repeats, params_.dutyPct, stageCount_);
+    Log::printf("CONFIG", "mode=%s range=%s..%s adjacent accuracy=%.2f%% time=%lums duty=%u%% stages=%lu",
+      roleName(static_cast<Role>(settings_.role)), startText, endText,
+      params_.accuracyPct, params_.testTimeMs, params_.dutyPct, stageCount_);
  }
  printConfiguration();
  const Role role = static_cast<Role>(settings_.role);
@@ -207,28 +279,31 @@ void App::startTest() {
    state_ = AppState::SOLO_MEASURE;
  } else if (!radio_.begin()) finish(false, FailReason::LINK_LOST);
  else if (role == Role::MASTER) startMasterDiscovery();
-  else { state_ = AppState::SLAVE_READY; Log::event("TEST", "Slave armed and waiting for Master"); display_.show("SLAVE READY", "WAIT MASTER"); }
+  else { state_ = AppState::SLAVE_READY; Log::event("TEST", "Slave armed and waiting for Master"); display_.show(UiText::SLAVE_READY, UiText::WAIT_MASTER); }
 }

 bool App::armSlave(bool preserveDisplay) {
+  setActivePerformance(false);
+  lastUserActivityMs_ = millis();
  params_ = store_.params(settings_);
-  stageIndex_ = 0; stageCount_ = frequencyPointCount(params_.startHz, params_.endHz, params_.stepHz);
+  stageIndex_ = 0; stageCount_ = frequencyPointCount(params_.startHz, params_.endHz);
  requestedHz_ = 0; session_ = 0; sequence_ = 0; havePeer_ = false;
  lastHeartbeatMs_ = 0; lastPeerSeenMs_ = 0; retries_ = 0; slaveRearmAtMs_ = 0;
  if (!radio_.begin()) {
    state_ = AppState::FINISHED; pendingReason_ = FailReason::LINK_LOST;
    slaveRearmAtMs_ = millis() + LINK_HEARTBEAT_TIMEOUT_MS;
-    display_.show("LINK FAILED", "RADIO ERROR");
+    display_.show(UiText::LINK_FAILED, UiText::RADIO_ERROR);
    return false;
  }
+  radio_.setWindowedReceive(true);
  radio_.flush(); state_ = AppState::SLAVE_READY;
  Log::event("TEST", "Slave automatically armed and waiting for Master");
-  if (!preserveDisplay) display_.show("SLAVE READY", "WAIT MASTER");
+  if (!preserveDisplay) display_.show(UiText::SLAVE_READY, UiText::WAIT_MASTER);
  return true;
 }

 bool App::prepareStage(bool showProgress) {
-  requestedHz_ = frequencyAt(params_.startHz, params_.endHz, params_.stepHz, stageIndex_);
+  requestedHz_ = frequencyAt(params_.startHz, params_.endHz, stageIndex_);
  actual_ = {};
  const uint32_t maxHz = TARGET_IS_C3 ? C3_STRICT_MAX_HZ :
    (receiver_.highRateBackend() ? S3_STRICT_MAX_HZ : C3_STRICT_MAX_HZ);
@@ -239,11 +314,13 @@ bool App::prepareStage(bool showProgress) {
      GPIO_PWM, requestedHz_);
    finish(false, FailReason::RESOLUTION); return false;
  }
+  const uint32_t plannedRxHz = receiver_.plannedTickHz(actual_.actualHz, actual_.actualDutyPct);
  const FailReason resolution = validateResolution(actual_.actualHz, actual_.actualDutyPct, params_.accuracyPct,
-                                                   receiver_.tickHz(), actual_.bits);
+                                                   plannedRxHz, actual_.bits);
  if (resolution != FailReason::NONE) {
    Log::printf("PWM", "resolution rejected: actual=%luHz duty=%.3f%% bits=%u RXclock=%luHz tolerance=%.3f%%",
-      actual_.actualHz, actual_.actualDutyPct, actual_.bits, receiver_.tickHz(), params_.accuracyPct);
+      actual_.actualHz, actual_.actualDutyPct, actual_.bits, plannedRxHz,
+      effectiveTolerancePct(params_.accuracyPct));
    finish(false, resolution); return false;
  }
  Log::printf("PWM", "stage=%lu/%lu requested=%luHz actual=%luHz duty=%.2f%% bits=%u STARTED",
@@ -256,9 +333,10 @@ bool App::prepareStage(bool showProgress) {
 }

 bool App::startLocalMeasurement(float hz, float duty) {
-  Log::printf("MEASURE", "arming expected=%.3fHz duty=%.3f%% tolerance=%.3f%% settle=%u cycles window=%lums x%u; per-pulse logging suspended",
-    hz, duty, params_.accuracyPct, PWM_SETTLE_CYCLES, params_.testTimeMs, params_.repeats);
-  const bool ok = measurement_.start(hz, duty, params_.accuracyPct, params_.testTimeMs, params_.repeats, PWM_SETTLE_CYCLES);
+  Log::printf("MEASURE", "arming expected=%.3fHz duty=%.3f%% tolerance=%.3f%% RX=%luHz settle=%u cycles window=%lums; per-pulse logging suspended",
+    hz, duty, effectiveTolerancePct(params_.accuracyPct), receiver_.plannedTickHz(static_cast<uint32_t>(hz + 0.5f), duty),
+    PWM_SETTLE_CYCLES, params_.testTimeMs);
+  const bool ok = measurement_.start(hz, duty, params_.accuracyPct, params_.testTimeMs, PWM_SETTLE_CYCLES);
  Log::printf("MEASURE", "receiver start %s, RMT chunk=%u symbols", ok ? "OK" : "FAILED",
    receiver_.receiveChunkSymbols());
  return ok;
@@ -270,7 +348,7 @@ void App::stagePassed() {
  if (++stageIndex_ >= stageCount_) { finish(true, FailReason::NONE); return; }
  if (static_cast<Role>(settings_.role) == Role::SOLO) { if (prepareStage()) state_ = AppState::SOLO_MEASURE; }
  else if (static_cast<Role>(settings_.role) == Role::MASTER) {
-    requestedHz_ = frequencyAt(params_.startHz, params_.endHz, params_.stepHz, stageIndex_);
+    requestedHz_ = frequencyAt(params_.startHz, params_.endHz, stageIndex_);
    actual_ = {};
    stageStartConfirmed_ = false;
    pendingPacket_ = makePacket(MessageType::PREPARE); sendCurrent(MessageType::PREPARE);
@@ -284,7 +362,7 @@ void App::startMasterDiscovery() {
  pendingPacket_ = makePacket(MessageType::DISCOVER); radio_.sendBroadcast(pendingPacket_);
  lastSendMs_ = millis(); retries_ = 0;
  state_ = AppState::MASTER_DISCOVER; Log::printf("ESP-NOW", "discovery started session=%08lX", session_);
-  display_.show("MASTER SEARCH", "HOLD START=STOP");
+  display_.show(UiText::MASTER_SEARCH, UiText::HOLD_START_STOP);
 }

 ProtocolPacket App::makePacket(MessageType type) const {
@@ -294,7 +372,7 @@ ProtocolPacket App::makePacket(MessageType type) const {
  p.requestedHz = requestedHz_; p.actualHz = actual_.actualHz;
  const float packetDuty = actual_.actualDutyPct > 0.0f ? actual_.actualDutyPct : params_.dutyPct;
  p.actualDutyX100 = static_cast<uint16_t>(packetDuty * 100.0f + 0.5f);
-  p.testTimeMs = params_.testTimeMs; p.repeats = params_.repeats;
+  p.testTimeMs = params_.testTimeMs;
  p.accuracyX100 = static_cast<uint16_t>(params_.accuracyPct * 100.0f + 0.5f); p.settleCycles = PWM_SETTLE_CYCLES;
  return p;
 }
@@ -342,14 +420,17 @@ void App::handleRadio() {
        messageName(type), r.packet.session, r.packet.stage, r.packet.sequence);
    if ((state_ == AppState::SLAVE_READY || state_ == AppState::SLAVE_WAIT_START) &&
        type == MessageType::DISCOVER && (!havePeer_ || !memcmp(peer_, r.mac, 6))) {
+      leaveIdlePowerSave();
+      setActivePerformance(true);
+      radio_.setWindowedReceive(false);
      memcpy(peer_, r.mac, 6); havePeer_ = true; session_ = r.packet.session; stageIndex_ = 0; sequence_ = r.packet.sequence;
      lastPeerSeenMs_ = millis();
      ProtocolPacket ack = makePacket(MessageType::DISCOVER_ACK); ack.sequence = r.packet.sequence; sendLinked(ack);
-      state_ = AppState::SLAVE_WAIT_START; display_.show("MASTER SEEN", "ACK SENT"); continue;
+      state_ = AppState::SLAVE_WAIT_START; display_.show(UiText::MASTER_SEEN, UiText::ACK_SENT); continue;
    }
    if (state_ == AppState::MASTER_DISCOVER && type == MessageType::DISCOVER_ACK && r.packet.session == session_) {
      memcpy(peer_, r.mac, 6); havePeer_ = true; lastPeerSeenMs_ = lastHeartbeatMs_ = millis();
-      requestedHz_ = frequencyAt(params_.startHz, params_.endHz, params_.stepHz, stageIndex_);
+      requestedHz_ = frequencyAt(params_.startHz, params_.endHz, stageIndex_);
      sendCurrent(MessageType::PREPARE); state_ = AppState::MASTER_WAIT_READY; retries_ = 0; deadlineMs_ = millis() + LINK_REPLY_TIMEOUT_MS;
      char mac[20]; Radio::macText(peer_, mac, sizeof(mac)); Log::printf("ESP-NOW", "Slave selected %s", mac); continue;
    }
@@ -374,7 +455,7 @@ void App::handleRadio() {
        stageIndex_ = r.packet.stage;
        sequence_ = r.packet.sequence;
        state_ = AppState::SLAVE_WAIT_START;
-        params_.testTimeMs = r.packet.testTimeMs; params_.repeats = r.packet.repeats;
+        params_.testTimeMs = r.packet.testTimeMs;
        params_.accuracyPct = r.packet.accuracyX100 / 100.0f; requestedHz_ = r.packet.requestedHz;
        stageCount_ = r.packet.stageCount;
        actual_ = {};
@@ -402,11 +483,12 @@ void App::handleRadio() {
               r.packet.sequence == pendingPacket_.sequence) {
      if (!stageStartConfirmed_) showStageProgress();
      stageStartConfirmed_ = true;
-      deadlineMs_ = millis() + params_.testTimeMs * params_.repeats + LINK_REPLY_TIMEOUT_MS +
-        (1000UL * PWM_SETTLE_CYCLES / actual_.actualHz) + 20;
+      deadlineMs_ = millis() + stageWallTimeMs(params_.testTimeMs, actual_.actualHz) +
+        LINK_REPLY_TIMEOUT_MS + 20;
    } else if (state_ == AppState::MASTER_WAIT_RESULT && type == MessageType::PROGRESS) {
      stageStartConfirmed_ = true;
-      deadlineMs_ = millis() + params_.testTimeMs * params_.repeats + LINK_REPLY_TIMEOUT_MS;
+      deadlineMs_ = millis() + stageWallTimeMs(params_.testTimeMs, actual_.actualHz) +
+        LINK_REPLY_TIMEOUT_MS;
      showRemoteResult(r.packet);
    } else if (state_ == AppState::MASTER_WAIT_RESULT && type == MessageType::RESULT) {
      ProtocolPacket ack = makePacket(MessageType::ACK); ack.sequence = r.packet.sequence;
@@ -428,7 +510,8 @@ void App::handleRadio() {
      actual_.actualHz = r.packet.actualHz; actual_.actualDutyPct = r.packet.actualDutyX100 / 100.0f;
      if (!startLocalMeasurement(actual_.actualHz, actual_.actualDutyPct)) { finish(false, FailReason::UNSUPPORTED); continue; }
      showStageProgress();
-      state_ = AppState::SLAVE_MEASURE; deadlineMs_ = millis() + params_.testTimeMs * params_.repeats + LINK_REPLY_TIMEOUT_MS;
+      state_ = AppState::SLAVE_MEASURE;
+      deadlineMs_ = millis() + stageWallTimeMs(params_.testTimeMs, actual_.actualHz) + LINK_REPLY_TIMEOUT_MS;
      ProtocolPacket started = makePacket(MessageType::READY);
      started.sequence = r.packet.sequence; sendLinked(started);
    } else if (state_ == AppState::SLAVE_MEASURE && type == MessageType::START_STAGE) {
@@ -440,7 +523,7 @@ void App::handleRadio() {
      if (pendingPacket_.passed) {
        if (r.packet.passed) {
          radio_.end(); pendingReason_ = FailReason::NONE;
-          if (armSlave(true)) display_.show("SLAVE PASS", "WAIT MASTER");
+          if (armSlave(true)) display_.show(UiText::PASS_WORD, UiText::WAIT_MASTER);
        } else {
          stageIndex_ = static_cast<uint32_t>(r.packet.stage) + 1U;
          state_ = AppState::SLAVE_WAIT_START;
@@ -454,8 +537,9 @@ void App::handleRadio() {
 void App::updateMaster() {
  const uint32_t now = millis();
  if (state_ == AppState::MASTER_DISCOVER) {
-    if (now - lastSendMs_ >= LINK_RETRY_INTERVAL_MS) {
-      Log::event("ESP-NOW", "DISCOVER retry"); radio_.sendBroadcast(pendingPacket_);
+    if (now - lastSendMs_ >= DISCOVERY_RETRY_INTERVAL_MS) {
+      if (++retries_ % 50U == 0U) Log::event("ESP-NOW", "DISCOVER burst continues");
+      radio_.sendBroadcast(pendingPacket_);
      lastSendMs_ = now;
    }
    return;
@@ -475,7 +559,7 @@ void App::updateMaster() {
  Log::printf("ESP-NOW", "%s retry=%u", messageName(static_cast<MessageType>(pendingPacket_.type)), retries_ + 1);
  sendLinked(pendingPacket_); ++retries_;
  deadlineMs_ = now + (state_ == AppState::MASTER_WAIT_RESULT ?
-    (stageStartConfirmed_ ? params_.testTimeMs * params_.repeats + LINK_REPLY_TIMEOUT_MS : LINK_RETRY_INTERVAL_MS) :
+    (stageStartConfirmed_ ? stageWallTimeMs(params_.testTimeMs, actual_.actualHz) + LINK_REPLY_TIMEOUT_MS : LINK_RETRY_INTERVAL_MS) :
    LINK_REPLY_TIMEOUT_MS);
 }

@@ -488,10 +572,9 @@ void App::updateSlave() {
      StageStats live = {};
      if (measurement_.statsSnapshot(live)) {
        ProtocolPacket progress = makePacket(MessageType::PROGRESS);
+        progress.progressStep = measurement_.progressStep();
        fillMeasuredResult(progress, live);
        progress.sequence = sequence_; sendLinked(progress);
-        // oled.display() is synchronous. Resume capture only after the full
-        // framebuffer has reached the display.
        showStageResult(live);
      }
      measurement_.continueAfterDisplay();
@@ -503,6 +586,8 @@ void App::updateSlave() {
    printStageStats(measurement_.stats(), actual_.actualHz);
    showStageResult(measurement_.stats());
    pendingPacket_ = makePacket(MessageType::RESULT);
+    pendingPacket_.progressStep = ms == MeasureState::PASS ?
+      MEASUREMENT_PROGRESS_STEPS : measurement_.progressStep();
    pendingPacket_.passed = ms == MeasureState::PASS && measurement_.reason() == FailReason::NONE;
    pendingPacket_.reason = static_cast<uint8_t>(measurement_.reason()); pendingPacket_.periods = measurement_.stats().periods;
    fillMeasuredResult(pendingPacket_, measurement_.stats());
@@ -552,31 +637,94 @@ void App::finish(bool pass, FailReason reason, bool preserveDisplay) {
  if (!pass && masterActive && havePeer_ && reason != FailReason::ABORTED) sendAbort(reason);
  if (state_ != AppState::IDLE && state_ != AppState::MENU) radio_.end();
  state_ = AppState::FINISHED; pendingReason_ = reason;
+  setActivePerformance(false);
+  lastUserActivityMs_ = millis();
  if (slaveLinkLost) {
-    char target[12], one[24];
+    char target[12], one[64];
    Display::formatTestFrequency(actual_.actualHz ? actual_.actualHz : requestedHz_, target, sizeof(target));
-    snprintf(one, sizeof(one), "FAIL %s %.0f%%", target,
+    snprintf(one, sizeof(one), UiText::FAIL_FORMAT, target,
      actual_.actualDutyPct > 0.0f ? actual_.actualDutyPct : params_.dutyPct);
-    display_.show(one, failName(reason), stageIndex_ + 1, stageCount_);
+    display_.show(one, uiFailName(reason), stageIndex_ + 1, stageCount_);
    armSlave(true);
    return;
  }
  if (static_cast<Role>(settings_.role) == Role::SLAVE) slaveRearmAtMs_ = millis() + 2000;
  if (preserveDisplay) return;
-  char one[24];
+  char one[64];
  if (pass) {
    const Role role = static_cast<Role>(settings_.role);
-    snprintf(one, sizeof(one), "%s PASS", roleName(role));
-    display_.show(one, role == Role::SLAVE ? "WAIT MASTER" : "START=REPEAT");
+    snprintf(one, sizeof(one), "%s %s", uiRoleName(role), UiText::PASS_WORD);
+    display_.show(one, role == Role::SLAVE ? UiText::WAIT_MASTER : UiText::START_AGAIN);
  }
  else if (requestedHz_) {
    char frequency[12];
    Display::formatTestFrequency(actual_.actualHz ? actual_.actualHz : requestedHz_, frequency, sizeof(frequency));
-    snprintf(one, sizeof(one), "FAIL %s %.0f%%", frequency,
+    snprintf(one, sizeof(one), UiText::FAIL_FORMAT, frequency,
      actual_.actualDutyPct > 0.0f ? actual_.actualDutyPct : params_.dutyPct);
-    display_.show(one, failName(reason), stageIndex_ + 1, stageCount_);
+    display_.show(one, uiFailName(reason), stageIndex_ + 1, stageCount_);
  } else {
-    display_.show("TEST FAILED", failName(reason));
+    display_.show(UiText::TEST_FAILED, uiFailName(reason));
+  }
+}
+
+bool App::idlePowerSaveAllowed() const {
+  return initialized_ && (state_ == AppState::IDLE || state_ == AppState::MENU ||
+    state_ == AppState::FINISHED || state_ == AppState::SLAVE_READY);
+}
+
+void App::setActivePerformance(bool active) {
+  const uint32_t targetMhz = active ? 160U : 80U;
+  if (getCpuFrequencyMhz() != targetMhz && !setCpuFrequencyMhz(targetMhz))
+    Log::printf("POWER", "CPU frequency change to %luMHz FAILED", targetMhz);
+}
+
+void App::leaveIdlePowerSave(bool wakeDisplay) {
+  if (!idlePowerSave_) {
+    if (wakeDisplay) display_.setPower(true);
+    return;
+  }
+  idlePowerSave_ = false;
+  lastUserActivityMs_ = millis();
+  if (wakeDisplay) display_.setPower(true);
+  Log::event("POWER", "idle light sleep ended");
+}
+
+void App::serviceIdlePowerSave() {
+  if (!idlePowerSaveAllowed()) {
+    leaveIdlePowerSave(false);
+    return;
+  }
+
+  const uint32_t now = millis();
+  if (!idlePowerSave_) {
+    if (now - lastUserActivityMs_ < IDLE_POWER_SAVE_TIMEOUT_MS) {
+      delay(1); // allow the FreeRTOS idle task to halt the CPU between UI polls
+      return;
+    }
+    idlePowerSave_ = true;
+    display_.setPower(false);
+    Log::event("POWER", "idle timeout; OLED off and light sleep started");
+  }
+
+  gpio_wakeup_enable(static_cast<gpio_num_t>(GPIO_BUTTON_START),
+    BUTTON_ACTIVE_LEVEL == LOW ? GPIO_INTR_LOW_LEVEL : GPIO_INTR_HIGH_LEVEL);
+  gpio_wakeup_enable(static_cast<gpio_num_t>(GPIO_BUTTON_MODE),
+    BUTTON_ACTIVE_LEVEL == LOW ? GPIO_INTR_LOW_LEVEL : GPIO_INTR_HIGH_LEVEL);
+  esp_sleep_enable_gpio_wakeup();
+  esp_sleep_enable_timer_wakeup(IDLE_LIGHT_SLEEP_SLICE_US);
+  const esp_err_t result = esp_light_sleep_start();
+  if (result != ESP_OK) {
+    delay(1);
+    return;
+  }
+
+  if (esp_sleep_get_wakeup_cause() == ESP_SLEEP_WAKEUP_GPIO) {
+    // The wake-up press is deliberately consumed. Holding or releasing it
+    // must not later turn into a SHORT, LONG, or REPEAT event.
+    startButton_.suppressUntilRelease();
+    modeButton_.suppressUntilRelease();
+    leaveIdlePowerSave();
+    Log::event("POWER", "button wake consumed; next press will perform the action");
  }
 }

@@ -588,11 +736,11 @@ void App::printConfiguration() {
  Serial.printf("MAC=%02X:%02X:%02X:%02X:%02X:%02X\n", mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
  Serial.printf("GPIO PWM=%u RX=%u START=%u MODE=%u SDA=%u SCL=%u\n", GPIO_PWM, GPIO_RX,
    GPIO_BUTTON_START, GPIO_BUTTON_MODE, GPIO_SDA, GPIO_SCL);
-  Serial.printf("Test %lu..%lu step %lu Hz, accuracy %.2f%%, %lums x%u, duty %u%%\n",
-    params_.startHz, params_.endHz, params_.stepHz, params_.accuracyPct, params_.testTimeMs, params_.repeats, params_.dutyPct);
-  stageCount_ = frequencyPointCount(params_.startHz, params_.endHz, params_.stepHz);
+  Serial.printf("Test %lu..%lu Hz (adjacent exact frequencies), accuracy %.2f%%, %lums, duty %u%%\n",
+    params_.startHz, params_.endHz, params_.accuracyPct, params_.testTimeMs, params_.dutyPct);
+  stageCount_ = frequencyPointCount(params_.startHz, params_.endHz);
  Serial.printf("Frequencies (%lu): ", stageCount_);
-  for (uint32_t i = 0; i < stageCount_; ++i) Serial.printf("%lu%s", frequencyAt(params_.startHz, params_.endHz, params_.stepHz, i), i + 1 == stageCount_ ? "\n" : ",");
+  for (uint32_t i = 0; i < stageCount_; ++i) Serial.printf("%lu%s", frequencyAt(params_.startHz, params_.endHz, i), i + 1 == stageCount_ ? "\n" : ",");
  Serial.printf("ALL nominal: %llu us | RX=%s\n", actualNominalTotalUs(), receiver_.highRateBackend() ? "RMT DMA" : "RMT ping-pong");
 }

@@ -617,64 +765,69 @@ void App::printStageStats(const StageStats &s, uint32_t hz) {
 }

 void App::showStageResult(const StageStats &s) {
-  char one[24], two[24];
+  char one[64], two[64];
  char target[12]; Display::formatTestFrequency(actual_.actualHz, target, sizeof(target));
  if (s.reason != FailReason::NONE) {
-    snprintf(one, sizeof(one), "FAIL %s %.0f%%", target, actual_.actualDutyPct);
+    snprintf(one, sizeof(one), UiText::FAIL_FORMAT, target, actual_.actualDutyPct);
    if (s.reason == FailReason::PERIOD_OUT && s.badFrequency > 0.0f) {
      char frequency[12];
      Display::formatTestFrequency(static_cast<uint32_t>(lroundf(s.badFrequency)), frequency, sizeof(frequency));
-      snprintf(two, sizeof(two), "PERIOD OUT %s", frequency);
+      snprintf(two, sizeof(two), UiText::PERIOD_OUT_FORMAT, frequency);
    } else if (s.reason == FailReason::DUTY_OUT && s.badFrequency > 0.0f) {
      char duty[10]; formatErrorDuty(s.badDuty, duty, sizeof(duty));
-      snprintf(two, sizeof(two), "DUTY OUT %s", duty);
+      snprintf(two, sizeof(two), UiText::DUTY_OUT_FORMAT, duty);
    } else {
-      snprintf(two, sizeof(two), "%s", failName(s.reason));
+      snprintf(two, sizeof(two), "%s", uiFailName(s.reason));
    }
-    display_.show(one, two, stageIndex_ + 1, stageCount_);
+    display_.show(one, two, overallProgress(stageIndex_, measurement_.progressStep()),
+      overallProgressTotal(stageCount_));
    return;
  }
-  snprintf(one, sizeof(one), "Test:%-6s %2.0f%% %2lu/%2lu",
-    target, actual_.actualDutyPct, stageIndex_ + 1, stageCount_);
+  char stage[12]; snprintf(stage, sizeof(stage), "%lu/%lu", stageIndex_ + 1, stageCount_);
+  snprintf(one, sizeof(one), UiText::TEST_FORMAT, target, actual_.actualDutyPct, stage);
  if (!s.periods || !s.periodSum) {
-    display_.show(one, "F:---      D:---%", stageIndex_ + 1, stageCount_);
+    display_.show(one, UiText::NO_MEASUREMENT, overallProgress(stageIndex_, measurement_.progressStep()),
+      overallProgressTotal(stageCount_));
    return;
  }
  const float measuredHz = static_cast<float>(receiver_.tickHz()) * s.periods / s.periodSum;
  const float measuredDuty = 100.0f * s.activeSum / s.periodSum;
  char frequency[12]; Display::formatFrequency(measuredHz, frequency, sizeof(frequency));
  snprintf(two, sizeof(two), "F:%-8s D:%4.1f%%", frequency, measuredDuty);
-  display_.show(one, two, stageIndex_ + 1, stageCount_);
+  display_.show(one, two, overallProgress(stageIndex_, measurement_.progressStep()),
+    overallProgressTotal(stageCount_));
 }

 void App::showRemoteResult(const ProtocolPacket &packet) {
  const FailReason reason = packet.reason <= static_cast<uint8_t>(FailReason::ABORTED)
    ? static_cast<FailReason>(packet.reason) : FailReason::UNSUPPORTED;
-  char target[12], one[24], two[24];
+  char target[12], one[64], two[64];
  Display::formatTestFrequency(packet.actualHz ? packet.actualHz : packet.requestedHz,
    target, sizeof(target));
  if (reason == FailReason::NONE) {
-    snprintf(one, sizeof(one), "Test:%-6s %2.0f%% %2lu/%2lu",
-      target, packet.actualDutyX100 / 100.0f, stageIndex_ + 1, stageCount_);
+    char stage[12]; snprintf(stage, sizeof(stage), "%lu/%lu", stageIndex_ + 1, stageCount_);
+    snprintf(one, sizeof(one), UiText::TEST_FORMAT,
+      target, packet.actualDutyX100 / 100.0f, stage);
    if (packet.measuredHzX10) {
      char measured[12];
      Display::formatFrequency(packet.measuredHzX10 / 10.0f, measured, sizeof(measured));
      snprintf(two, sizeof(two), "F:%-8s D:%4.1f%%", measured, packet.measuredDutyX10 / 10.0f);
-    } else snprintf(two, sizeof(two), "F:---      D:---%%");
+    } else snprintf(two, sizeof(two), "%s", UiText::NO_MEASUREMENT);
  } else if (reason == FailReason::PERIOD_OUT && packet.measuredHzX10) {
-    snprintf(one, sizeof(one), "FAIL %s %.0f%%", target, packet.actualDutyX100 / 100.0f);
+    snprintf(one, sizeof(one), UiText::FAIL_FORMAT, target, packet.actualDutyX100 / 100.0f);
    char measured[12];
    Display::formatTestFrequency((packet.measuredHzX10 + 5U) / 10U, measured, sizeof(measured));
-    snprintf(two, sizeof(two), "PERIOD OUT %s", measured);
+    snprintf(two, sizeof(two), UiText::PERIOD_OUT_FORMAT, measured);
  } else if (reason == FailReason::DUTY_OUT && packet.measuredDutyX10) {
-    snprintf(one, sizeof(one), "FAIL %s %.0f%%", target, packet.actualDutyX100 / 100.0f);
+    snprintf(one, sizeof(one), UiText::FAIL_FORMAT, target, packet.actualDutyX100 / 100.0f);
    char duty[10]; formatErrorDuty(packet.measuredDutyX10 / 10.0f, duty, sizeof(duty));
-    snprintf(two, sizeof(two), "DUTY OUT %s", duty);
+    snprintf(two, sizeof(two), UiText::DUTY_OUT_FORMAT, duty);
  } else {
-    snprintf(one, sizeof(one), "FAIL %s %.0f%%", target, packet.actualDutyX100 / 100.0f);
-    snprintf(two, sizeof(two), "%s", failName(reason));
+    snprintf(one, sizeof(one), UiText::FAIL_FORMAT, target, packet.actualDutyX100 / 100.0f);
+    snprintf(two, sizeof(two), "%s", uiFailName(reason));
  }
-  display_.show(one, two, stageIndex_ + 1, stageCount_);
+  display_.show(one, two, overallProgress(stageIndex_, packet.progressStep),
+    overallProgressTotal(stageCount_));
 }

 void App::fillMeasuredResult(ProtocolPacket &packet, const StageStats &stats) const {
@@ -691,9 +844,10 @@ void App::fillMeasuredResult(ProtocolPacket &packet, const StageStats &stats) co
 }

 void App::showStageProgress() {
-  char target[12], one[24];
+  char target[12], one[64], stage[12];
  Display::formatTestFrequency(actual_.actualHz, target, sizeof(target));
-  snprintf(one, sizeof(one), "Test:%-6s %2.0f%% %2lu/%2lu",
-    target, actual_.actualDutyPct, stageIndex_ + 1, stageCount_);
-  display_.show(one, "F:---      D:---%", stageIndex_ + 1, stageCount_);
+  snprintf(stage, sizeof(stage), "%lu/%lu", stageIndex_ + 1, stageCount_);
+  snprintf(one, sizeof(one), UiText::TEST_FORMAT, target, actual_.actualDutyPct, stage);
+  display_.show(one, UiText::NO_MEASUREMENT, overallProgress(stageIndex_, 0),
+    overallProgressTotal(stageCount_));
 }
--- a/OpticalChannelTester/App.h
+++ b/OpticalChannelTester/App.h
@@ -47,6 +47,10 @@ class App {
  void sendCurrent(MessageType type);
  void updateHeartbeat();
  bool packetForCurrent(const ProtocolPacket &p) const;
+  void serviceIdlePowerSave();
+  void leaveIdlePowerSave(bool wakeDisplay = true);
+  bool idlePowerSaveAllowed() const;
+  void setActivePerformance(bool active);

  Button startButton_, modeButton_;
  Display display_;
@@ -75,4 +79,6 @@ class App {
  uint32_t bootCheckStartedMs_ = 0;
  uint32_t slaveRearmAtMs_ = 0;
  bool stageStartConfirmed_ = false;
+  uint32_t lastUserActivityMs_ = 0;
+  bool idlePowerSave_ = false;
 };
--- a/OpticalChannelTester/Buttons.cpp
+++ b/OpticalChannelTester/Buttons.cpp
@@ -7,8 +7,21 @@ void Button::begin() {
  changedAt_ = millis();
 }

+void Button::suppressUntilRelease() {
+  suppressed_ = true;
+  raw_ = stable_ = (digitalRead(pin_) == BUTTON_ACTIVE_LEVEL);
+  changedAt_ = millis();
+  longSent_ = true;
+}
+
 ButtonEvent Button::update(uint32_t now) {
  const bool sample = (digitalRead(pin_) == BUTTON_ACTIVE_LEVEL);
+  if (suppressed_) {
+    raw_ = stable_ = sample;
+    changedAt_ = now;
+    if (!sample) { suppressed_ = false; longSent_ = false; }
+    return ButtonEvent::NONE;
+  }
  if (sample != raw_) { raw_ = sample; changedAt_ = now; }
  if (raw_ != stable_ && now - changedAt_ >= BUTTON_DEBOUNCE_MS) {
    stable_ = raw_;
--- a/OpticalChannelTester/Buttons.h
+++ b/OpticalChannelTester/Buttons.h
@@ -8,10 +8,12 @@ class Button {
  explicit Button(uint8_t pin) : pin_(pin) {}
  void begin();
  ButtonEvent update(uint32_t nowMs);
+  void suppressUntilRelease();
  bool pressed() const { return stable_; }
 private:
  uint8_t pin_;
  bool raw_ = false, stable_ = false, longSent_ = false;
+  bool suppressed_ = false;
  uint32_t changedAt_ = 0, pressedAt_ = 0, nextRepeat_ = 0;
 };

--- a/OpticalChannelTester/Config.h
+++ b/OpticalChannelTester/Config.h
@@ -3,23 +3,43 @@
 #include <Arduino.h>

 // ------------------------- Hardware configuration -------------------------
+// Uncomment for the hand-wired prototype. The production PCB assignments
+// below follow the physical header positions shown in the schematic.
+// #define MAKETKA
+
 #if CONFIG_IDF_TARGET_ESP32C3
 constexpr bool TARGET_IS_C3 = true;
 constexpr uint8_t GPIO_PWM = 3;
 constexpr uint8_t GPIO_RX = 4;
+#ifdef MAKETKA
 constexpr uint8_t GPIO_BUTTON_MODE = 0;
 constexpr uint8_t GPIO_BUTTON_START = 1;
+#else
+constexpr uint8_t GPIO_BUTTON_MODE = 1;
+constexpr uint8_t GPIO_BUTTON_START = 0;
+#endif
 constexpr uint8_t GPIO_SDA = 6;
 constexpr uint8_t GPIO_SCL = 7;
 #elif CONFIG_IDF_TARGET_ESP32S3
 constexpr bool TARGET_IS_C3 = false;
+#ifdef MAKETKA
 constexpr uint8_t GPIO_PWM = 4;
 constexpr uint8_t GPIO_RX = 5;
-constexpr uint8_t GPIO_BUTTON_MODE = 6;
-constexpr uint8_t GPIO_BUTTON_START = 7;
+constexpr uint8_t GPIO_BUTTON_MODE = 0;
+constexpr uint8_t GPIO_BUTTON_START = 1;
 constexpr uint8_t GPIO_SDA = 8;
 constexpr uint8_t GPIO_SCL = 9;
 #else
+// The S3 SuperMini is fitted so its 5V and GND pins occupy the same PCB
+// contacts as on the C3 SuperMini. Signals therefore follow header position.
+constexpr uint8_t GPIO_PWM = 12;
+constexpr uint8_t GPIO_RX = 13;
+constexpr uint8_t GPIO_BUTTON_MODE = 10;
+constexpr uint8_t GPIO_BUTTON_START = 9;
+constexpr uint8_t GPIO_SDA = 44;
+constexpr uint8_t GPIO_SCL = 1;
+#endif
+#else
 #error "Only ESP32-C3 and ESP32-S3 are supported"
 #endif

@@ -38,7 +58,7 @@ constexpr bool SERIAL_MINIMAL_LOG = true;
 #define PWM_SETTLE_CYCLES 5U

 constexpr uint32_t BUTTON_DEBOUNCE_MS = 30;
-constexpr uint32_t BUTTON_LONG_PRESS_MS = 800;
+constexpr uint32_t BUTTON_LONG_PRESS_MS = 500;
 constexpr uint32_t BUTTON_REPEAT_DELAY_MS = 600;
 constexpr uint32_t BUTTON_REPEAT_MS = 180;
 constexpr uint32_t FACTORY_RESET_HOLD_MS = 1500;
@@ -46,6 +66,7 @@ constexpr uint32_t FACTORY_RESET_HOLD_MS = 1500;
 constexpr uint32_t LINK_REPLY_TIMEOUT_MS = 1500;
 constexpr uint8_t LINK_PACKET_RETRIES = 10;
 constexpr uint32_t LINK_RETRY_INTERVAL_MS = 1000;
+constexpr uint32_t DISCOVERY_RETRY_INTERVAL_MS = 20;
 constexpr uint32_t LINK_HEARTBEAT_INTERVAL_MS = 500;
 constexpr uint32_t LINK_HEARTBEAT_TIMEOUT_MS = 2500;
 constexpr uint32_t FINAL_ACK_RETRY_INTERVAL_MS = 50;
@@ -57,28 +78,51 @@ constexpr uint32_t RMT_TARGET_CHUNK_US = 5000;
 constexpr uint8_t RMT_QUEUE_BLOCKS = 8;
 constexpr uint16_t PERIOD_BATCH_SIZE = 128;
 constexpr uint8_t MEASUREMENT_PROGRESS_STEPS = 10;
+constexpr uint32_t OLED_PROGRESS_UPDATE_MS = 15;
+
+constexpr uint32_t IDLE_POWER_SAVE_TIMEOUT_MS = 60000;
+constexpr uint32_t IDLE_LIGHT_SLEEP_SLICE_US = 10000;
+constexpr uint16_t SLAVE_LISTEN_INTERVAL_MS = 100;
+constexpr uint16_t SLAVE_LISTEN_WINDOW_MS = 20;
+static_assert(SLAVE_LISTEN_WINDOW_MS < SLAVE_LISTEN_INTERVAL_MS,
+  "Slave listen window must be shorter than its interval");
+// Conservative sustained validation rate calibrated from real C3 logs.
+constexpr uint32_t RX_PROCESSING_PERIODS_PER_SECOND = 300000;

 constexpr uint32_t C3_STRICT_MAX_HZ = 1000000;
 constexpr uint32_t S3_STRICT_MAX_HZ = 1000000;
-// RMT stores each HIGH/LOW duration in 15 bits. At 80 MHz that limits a
-// single level to about 409 us, so even a 1 kHz signal with 50% duty cannot
-// be captured. 20 MHz still provides 20 ticks at 1 MHz (5% resolution),
-// while allowing level durations up to about 1.64 ms for the 1 kHz/90% case.
-constexpr uint32_t CAPTURE_RESOLUTION_HZ = 20000000;
-// Arduino-ESP32 uses the 40 MHz crystal as the default LEDC clock on C3/S3.
+// RMT stores each HIGH/LOW duration in 15 bits. Select the fastest clock that
+// still fits both levels of the current PWM signal: 20, 40 or 80 MHz.
+constexpr uint32_t CAPTURE_RESOLUTION_OPTIONS_HZ[] = {20000000, 40000000, 80000000};
+constexpr uint32_t RMT_MAX_LEVEL_TICKS = 32766;
+// C3 uses the 40 MHz crystal as the LEDC clock.
 // Keep this explicit so the resolution calculation never asks LEDC for an
 // impossible frequency/resolution combination.
 constexpr uint32_t LEDC_SOURCE_CLOCK_HZ = 40000000;
 constexpr uint8_t LEDC_CHANNEL = 0;
 constexpr uint8_t LEDC_MAX_BITS = 14;
+// S3 uses the dedicated MCPWM peripheral. A 40 MHz timer clock keeps the
+// longest 1 kHz period within the S3's 16-bit MCPWM counter and makes every
+// frequency in TEST_FREQUENCIES_HZ exact.
+constexpr uint32_t MCPWM_RESOLUTION_HZ = 40000000;
+constexpr uint32_t MCPWM_MAX_PERIOD_TICKS = 65535;

 // -------------------------- Menu value arrays -----------------------------
-constexpr uint32_t START_FREQ_OPTIONS_HZ[] = {1000, 2000, 5000, 10000, 20000, 50000};
-constexpr uint32_t END_FREQ_OPTIONS_HZ[] = {100000, 200000, 500000, 750000, 1000000};
-constexpr uint32_t STEP_OPTIONS_HZ[] = {1000, 2000, 5000, 10000, 20000, 50000, 100000};
+// START and END deliberately have separate, independently cycling menu lists.
+// Every value is exactly achievable from a 40 MHz timer clock. The test walks
+// TEST_FREQUENCIES_HZ between the selected endpoints, so there is no
+// separately configurable step.
+constexpr uint32_t START_FREQ_OPTIONS_HZ[] = {1000, 10000, 100000};
+constexpr uint32_t END_FREQ_OPTIONS_HZ[] = {100000, 500000, 1000000};
+
+// All achievable whole-number frequencies in the supported 1 kHz..1 MHz
+// range, used for adjacent test stages rather than direct menu selection.
+constexpr uint32_t TEST_FREQUENCIES_HZ[] = {
+  1000, 2000, 5000, 10000, 25000, 50000,
+  100000, 200000, 312500, 400000, 500000, 625000, 800000, 1000000
+};
 constexpr float ACCURACY_OPTIONS_PCT[] = {1.0f, 2.0f, 5.0f, 10.0f};
 constexpr uint32_t TEST_TIME_OPTIONS_MS[] = {100, 250, 500, 1000, 2000, 5000};
-constexpr uint8_t REPEAT_OPTIONS[] = {1, 2, 3, 5, 10};
 constexpr uint8_t DUTY_OPTIONS_PCT[] = {10, 25, 50, 75, 90};

 template <typename T, size_t N> constexpr size_t countOf(const T (&)[N]) { return N; }
--- a/OpticalChannelTester/Config_Text.h
+++ b/OpticalChannelTester/Config_Text.h
@@ -0,0 +1,118 @@
+#pragma once
+
+// Select the language used by the OLED interface.
+// Build with UI_LANGUAGE_EN for English or UI_LANGUAGE_RU for Russian.
+#define UI_LANGUAGE_EN 0
+#define UI_LANGUAGE_RU 1
+
+#ifndef UI_LANGUAGE
+#define UI_LANGUAGE UI_LANGUAGE_RU
+#endif
+
+namespace UiText {
+
+#if UI_LANGUAGE == UI_LANGUAGE_RU
+
+constexpr const char *ROLE_NAMES[] = {
+  "СОЛО", "МАСТЕР", "СЛЕЙВ"
+};
+
+constexpr const char *FAIL_NAMES[] = {
+  "НЕТ ОШИБКИ",
+  "НЕТ СИГНАЛА",
+  "ПЕРИОД ВНЕ ДОПУСКА",
+  "ЗАПОЛН. ВНЕ ДОПУСКА",
+  "ЛИШНИЙ ФРОНТ",
+  "ИМПУЛЬСНАЯ ПОМЕХА",
+  "ПРОПУЩЕН ФРОНТ",
+  "ОШИБКА ПОТЕРИ ДАННЫХ",
+  "СВЯЗЬ ПОТЕРЯНА",
+  "РЕЖИМ НЕ ПОДДЕРЖИВ.",
+  "НЕ ХВАТАЕТ ТОЧНОСТИ",
+  "ТЕСТ ОСТАНОВЛЕН"
+};
+
+constexpr const char *MODE_PREFIX = "РЕЖИМ: ";
+constexpr const char *START_RUN = "ГОТОВ К ЗАПУСКУ";
+
+constexpr const char *MENU_START_FREQUENCY = "ЧАСТОТА ОТ:";
+constexpr const char *MENU_END_FREQUENCY = "ЧАСТОТА ДО:";
+constexpr const char *MENU_ACCURACY = "ТОЧНОСТЬ:";
+constexpr const char *MENU_TEST_TIME = "ВРЕМЯ ВЫБОРКИ:";
+constexpr const char *MENU_PWM_DUTY = "ЗАПОЛНЕНИЕ:";
+constexpr const char *MENU_TOTAL_TIME = "ОБЩЕЕ ВРЕМЯ:";
+constexpr const char *FREQUENCY_UNIT = " Гц";
+
+constexpr const char *SLAVE_READY = "СЛЕЙВ ГОТОВ";
+constexpr const char *WAIT_MASTER = "ОЖИДАНИЕ МАСТЕРА";
+constexpr const char *LINK_FAILED = "СВЯЗЬ НЕ УСТАНОВЛЕНА";
+constexpr const char *RADIO_ERROR = "ОШИБКА СВЯЗИ";
+constexpr const char *MASTER_SEARCH = "ПОИСК СЛЕЙВА";
+constexpr const char *HOLD_START_STOP = "УДЕРЖ. START ДЛЯ СТОП";
+constexpr const char *MASTER_SEEN = "МАСТЕР ОБНАРУЖЕН";
+constexpr const char *ACK_SENT = "ОТВЕТ ОТПРАВЛЕН";
+constexpr const char *START_AGAIN = "ГОТОВ К ЗАПУСКУ";
+constexpr const char *TEST_FAILED = "ТЕСТ НЕ ПРОЙДЕН";
+
+constexpr const char *PASS_WORD = "ТЕСТ ПРОЙДЕН";
+constexpr const char *FAIL_FORMAT = "СБОЙ %s %.0f%%";
+constexpr const char *TEST_FORMAT = "Тест:%-6s %2.0f%% %5s";
+constexpr const char *PERIOD_OUT_FORMAT = "ОШИБКА ЧАСТОТЫ %s";
+constexpr const char *DUTY_OUT_FORMAT = "ОШИБКА ЗАПОЛН. %s";
+constexpr const char *NO_MEASUREMENT = "F:---      D:---%";
+
+#elif UI_LANGUAGE == UI_LANGUAGE_EN
+
+constexpr const char *ROLE_NAMES[] = {
+  "SOLO", "MASTER", "SLAVE"
+};
+
+constexpr const char *FAIL_NAMES[] = {
+  "NONE",
+  "NO SIGNAL",
+  "PERIOD OUT",
+  "DUTY OUT",
+  "EXTRA EDGE",
+  "GLITCH",
+  "LOST EDGE",
+  "DATA LOSS ERROR",
+  "LINK LOST",
+  "UNSUPPORTED",
+  "RESOLUTION",
+  "ABORTED"
+};
+
+constexpr const char *MODE_PREFIX = "MODE: ";
+constexpr const char *START_RUN = "READY TO START";
+
+constexpr const char *MENU_START_FREQUENCY = "START FREQ:";
+constexpr const char *MENU_END_FREQUENCY = "END FREQ:";
+constexpr const char *MENU_ACCURACY = "ACCURACY:";
+constexpr const char *MENU_TEST_TIME = "TEST TIME:";
+constexpr const char *MENU_PWM_DUTY = "PWM DUTY:";
+constexpr const char *MENU_TOTAL_TIME = "TOTAL TIME:";
+constexpr const char *FREQUENCY_UNIT = " Hz";
+
+constexpr const char *SLAVE_READY = "SLAVE READY";
+constexpr const char *WAIT_MASTER = "WAIT MASTER";
+constexpr const char *LINK_FAILED = "LINK FAILED";
+constexpr const char *RADIO_ERROR = "RADIO ERROR";
+constexpr const char *MASTER_SEARCH = "MASTER SEARCH";
+constexpr const char *HOLD_START_STOP = "HOLD START TO STOP";
+constexpr const char *MASTER_SEEN = "MASTER SEEN";
+constexpr const char *ACK_SENT = "ACK SENT";
+constexpr const char *START_AGAIN = "READY TO START";
+constexpr const char *TEST_FAILED = "TEST FAILED";
+
+constexpr const char *PASS_WORD = "TEST PASS";
+constexpr const char *FAIL_FORMAT = "FAIL %s %.0f%%";
+constexpr const char *TEST_FORMAT = "Test:%-6s %2.0f%% %5s";
+constexpr const char *PERIOD_OUT_FORMAT = "PERIOD OUT %s";
+constexpr const char *DUTY_OUT_FORMAT = "DUTY OUT %s";
+constexpr const char *NO_MEASUREMENT = "F:---      D:---%";
+
+#else
+#error "UI_LANGUAGE must be UI_LANGUAGE_EN or UI_LANGUAGE_RU"
+#endif
+
+}  // namespace UiText
--- a/OpticalChannelTester/Core.cpp
+++ b/OpticalChannelTester/Core.cpp
@@ -1,4 +1,5 @@
 #include "Core.h"
+#include "Config.h"
 #include <math.h>
 #include <string.h>

@@ -10,7 +11,7 @@ const char *roleName(Role r) {

 const char *failName(FailReason r) {
  static const char *names[] = {"NONE", "NO SIGNAL", "PERIOD OUT", "DUTY OUT",
-    "EXTRA EDGE", "GLITCH", "LOST EDGE", "TOO FEW PERIODS", "LINK LOST",
+    "EXTRA EDGE", "GLITCH", "LOST EDGE", "DATA LOSS ERROR", "LINK LOST",
    "UNSUPPORTED", "RESOLUTION", "ABORTED"};
  const uint8_t i = static_cast<uint8_t>(r);
  return i < (sizeof(names) / sizeof(names[0])) ? names[i] : "UNKNOWN";
@@ -30,28 +31,52 @@ uint32_t settingsChecksum(const Settings &s) {
  return hash;
 }

-uint32_t frequencyPointCount(uint32_t startHz, uint32_t endHz, uint32_t stepHz) {
-  if (!startHz || !stepHz || endHz <= startHz) return 0;
-  const uint64_t span = static_cast<uint64_t>(endHz) - startHz;
-  return static_cast<uint32_t>(span / stepHz + 1U + ((span % stepHz) ? 1U : 0U));
+uint32_t frequencyPointCount(uint32_t startHz, uint32_t endHz) {
+  if (!startHz || endHz <= startHz) return 0;
+  uint32_t count = 0;
+  for (size_t i = 0; i < countOf(TEST_FREQUENCIES_HZ); ++i)
+    if (TEST_FREQUENCIES_HZ[i] >= startHz && TEST_FREQUENCIES_HZ[i] <= endHz) ++count;
+  return count;
 }

-uint32_t frequencyAt(uint32_t startHz, uint32_t endHz, uint32_t stepHz, uint32_t index) {
-  const uint32_t count = frequencyPointCount(startHz, endHz, stepHz);
-  if (!count || index >= count) return 0;
-  if (index == count - 1) return endHz;
-  const uint64_t v = static_cast<uint64_t>(startHz) + static_cast<uint64_t>(stepHz) * index;
-  return v < endHz ? static_cast<uint32_t>(v) : endHz;
+uint32_t frequencyAt(uint32_t startHz, uint32_t endHz, uint32_t index) {
+  for (size_t i = 0; i < countOf(TEST_FREQUENCIES_HZ); ++i) {
+    const uint32_t frequency = TEST_FREQUENCIES_HZ[i];
+    if (frequency < startHz || frequency > endHz) continue;
+    if (!index--) return frequency;
+  }
+  return 0;
+}
+
+uint64_t nominalStageUs(uint32_t frequencyHz, uint32_t sampleTimeMs, uint32_t settleCycles) {
+  if (!frequencyHz || !sampleTimeMs) return 0;
+  const uint64_t sampleUs = static_cast<uint64_t>(sampleTimeMs) * 1000ULL;
+  // At high frequency the CPU needs longer than the requested sample window
+  // to validate every captured period. Use the measured sustained C3 rate.
+  const uint64_t processingUs =
+    (static_cast<uint64_t>(frequencyHz) * sampleTimeMs * 1000ULL +
+      RX_PROCESSING_PERIODS_PER_SECOND - 1U) / RX_PROCESSING_PERIODS_PER_SECOND;
+  const uint64_t samplingWallUs = processingUs > sampleUs ? processingUs : sampleUs;
+
+  uint64_t chunkSymbols =
+    (static_cast<uint64_t>(frequencyHz) * RMT_TARGET_CHUNK_US + 999999ULL) / 1000000ULL;
+  if (chunkSymbols < RMT_MIN_RECEIVE_SYMBOLS) chunkSymbols = RMT_MIN_RECEIVE_SYMBOLS;
+  if (chunkSymbols > RMT_MAX_RECEIVE_SYMBOLS) chunkSymbols = RMT_MAX_RECEIVE_SYMBOLS;
+  const uint64_t batchWaitUs =
+    ((chunkSymbols * 1000000ULL + frequencyHz - 1U) / frequencyHz) * MEASUREMENT_PROGRESS_STEPS;
+  const uint64_t settleUs =
+    (1000000ULL * settleCycles * MEASUREMENT_PROGRESS_STEPS + frequencyHz - 1U) / frequencyHz;
+  // Initial stage screen, nine intermediate screens and the final result.
+  const uint64_t displayUs = static_cast<uint64_t>(OLED_PROGRESS_UPDATE_MS) * 1000ULL *
+    (MEASUREMENT_PROGRESS_STEPS + 1U);
+  return samplingWallUs + batchWaitUs + settleUs + displayUs;
 }

 uint64_t nominalTotalUs(const TestParams &p, uint32_t settleCycles) {
  uint64_t total = 0;
-  const uint32_t count = frequencyPointCount(p.startHz, p.endHz, p.stepHz);
-  for (uint32_t i = 0; i < count; ++i) {
-    const uint32_t f = frequencyAt(p.startHz, p.endHz, p.stepHz, i);
-    total += (1000000ULL * settleCycles + f - 1) / f;
-    total += static_cast<uint64_t>(p.testTimeMs) * 1000ULL * p.repeats;
-  }
+  const uint32_t count = frequencyPointCount(p.startHz, p.endHz);
+  for (uint32_t i = 0; i < count; ++i)
+    total += nominalStageUs(frequencyAt(p.startHz, p.endHz, i), p.testTimeMs, settleCycles);
  return total;
 }

@@ -63,6 +88,10 @@ bool dutyWithin(float measured, float expected, float tolerance) {
  return fabsf(measured - expected) <= tolerance + 0.0001f;
 }

+float effectiveTolerancePct(float configured) {
+  return configured > 0.0f && configured <= 1.0001f ? 1.25f : configured;
+}
+
 uint8_t choosePwmResolution(uint32_t frequencyHz, uint32_t sourceClockHz,
                            uint8_t maxBits) {
  if (!frequencyHz || !sourceClockHz || !maxBits) return 0;
@@ -148,7 +177,8 @@ FailReason validateResolution(uint32_t frequencyHz, float dutyPct, float accurac
  // Measurement uses the duty actually programmed into LEDC. A coarse PWM
  // step is not itself an error when the requested value (e.g. 50%) is exactly
  // representable; only the selected value's actual quantization matters.
-  return (timerPeriodError > accuracyPct || timerDutyError > accuracyPct)
+  const float effectiveAccuracy = effectiveTolerancePct(accuracyPct);
+  return (timerPeriodError > effectiveAccuracy || timerDutyError > effectiveAccuracy)
    ? FailReason::RESOLUTION : FailReason::NONE;
 }

--- a/OpticalChannelTester/Core.h
+++ b/OpticalChannelTester/Core.h
@@ -6,7 +6,7 @@
 enum class Role : uint8_t { SOLO, MASTER, SLAVE };
 enum class FailReason : uint8_t {
  NONE, NO_SIGNAL, PERIOD_OUT, DUTY_OUT, EXTRA_EDGE, GLITCH, LOST_EDGE,
-  TOO_FEW_PERIODS, LINK_LOST, UNSUPPORTED, RESOLUTION, ABORTED
+  DATA_LOSS, LINK_LOST, UNSUPPORTED, RESOLUTION, ABORTED
 };

 const char *roleName(Role role);
@@ -17,10 +17,8 @@ struct Settings {
  uint8_t role;
  uint8_t startIndex;
  uint8_t endIndex;
-  uint8_t stepIndex;
  uint8_t accuracyIndex;
  uint8_t timeIndex;
-  uint8_t repeatIndex;
  uint8_t dutyIndex;
  uint32_t checksum;
 };
@@ -28,10 +26,8 @@ struct Settings {
 struct TestParams {
  uint32_t startHz;
  uint32_t endHz;
-  uint32_t stepHz;
  float accuracyPct;
  uint32_t testTimeMs;
-  uint8_t repeats;
  uint8_t dutyPct;
 };

@@ -72,11 +68,13 @@ struct IntegerPwmConfig {
 };

 uint32_t settingsChecksum(const Settings &s);
-uint32_t frequencyPointCount(uint32_t startHz, uint32_t endHz, uint32_t stepHz);
-uint32_t frequencyAt(uint32_t startHz, uint32_t endHz, uint32_t stepHz, uint32_t index);
+uint32_t frequencyPointCount(uint32_t startHz, uint32_t endHz);
+uint32_t frequencyAt(uint32_t startHz, uint32_t endHz, uint32_t index);
+uint64_t nominalStageUs(uint32_t frequencyHz, uint32_t sampleTimeMs, uint32_t settleCycles);
 uint64_t nominalTotalUs(const TestParams &p, uint32_t settleCycles);
 bool periodWithin(float measuredHz, float expectedHz, float tolerancePct);
 bool dutyWithin(float measuredPct, float expectedPct, float tolerancePct);
+float effectiveTolerancePct(float configuredPct);
 uint8_t choosePwmResolution(uint32_t frequencyHz, uint32_t sourceClockHz,
                            uint8_t maxBits);
 uint8_t chooseStablePwmResolution(uint32_t frequencyHz, uint32_t sourceClockHz,
--- a/OpticalChannelTester/Display.cpp
+++ b/OpticalChannelTester/Display.cpp
@@ -1,14 +1,31 @@
 #include "Display.h"
 #include "Config.h"
+#include "Font_Cyrillic.h"
 #include "Log.h"
 #include <Wire.h>
 #include <esp_log.h>
 #include <string.h>

+namespace {
+uint32_t nextUtf8Codepoint(const char *&text) {
+  const uint8_t first = static_cast<uint8_t>(*text++);
+  if (first < 0x80U) return first;
+  if ((first & 0xE0U) == 0xC0U) {
+    const uint8_t second = static_cast<uint8_t>(*text);
+    if ((second & 0xC0U) == 0x80U) {
+      ++text;
+      return ((first & 0x1FU) << 6) | (second & 0x3FU);
+    }
+  }
+  return '?';
+}
+}
+
 Display::Display() : oled_(128, 32, &Wire, -1) {}

 bool Display::begin() {
  Wire.begin(GPIO_SDA, GPIO_SCL);
+  Wire.setClock(400000); // keeps a full 128x32 framebuffer update near 15 ms
  // An absent optional OLED produces a large burst of ESP-IDF NACK messages.
  // Probe it once and keep the I2C driver quiet when no display is connected.
  esp_log_level_set("i2c.master", ESP_LOG_NONE);
@@ -23,29 +40,51 @@ bool Display::begin() {
    oled_.setRotation(OLED_ROTATION);
    oled_.setTextColor(SSD1306_WHITE);
    oled_.setTextSize(1);
+    powered_ = true;
  }
  Log::printf("OLED", "initialization %s, I2C address=0x%02X", ok_ ? "OK" : "FAILED", OLED_ADDRESS);
  return ok_;
 }

-void Display::fit(char *s) {
-  int16_t x, y; uint16_t w, h;
-  while (*s) {
-    oled_.getTextBounds(s, 0, 0, &x, &y, &w, &h);
-    if (w <= 128) break;
-    s[strlen(s) - 1] = '\0';
+void Display::setPower(bool enabled) {
+  if (!ok_ || powered_ == enabled) return;
+  oled_.ssd1306_command(enabled ? SSD1306_DISPLAYON : SSD1306_DISPLAYOFF);
+  powered_ = enabled;
+  Log::printf("OLED", "display power %s", enabled ? "ON" : "OFF");
+}
+
+void Display::drawTextLine(const char *text, int16_t y) {
+  int16_t x = 0;
+  while (text && *text && x + CyrillicFont::WIDTH <= oled_.width()) {
+    const uint32_t codepoint = nextUtf8Codepoint(text);
+    const uint8_t *glyph = CyrillicFont::glyph(codepoint);
+    if (glyph) {
+      for (uint8_t row = 0; row < CyrillicFont::HEIGHT; ++row) {
+        const uint8_t pixels = pgm_read_byte(glyph + row);
+        for (uint8_t column = 0; column < CyrillicFont::WIDTH; ++column)
+          if (pixels & (1U << (CyrillicFont::WIDTH - 1U - column)))
+            oled_.drawPixel(x + column, y + row, SSD1306_WHITE);
+      }
+    } else if (codepoint < 0x100U) {
+      oled_.drawChar(x, y, static_cast<unsigned char>(codepoint),
+        SSD1306_WHITE, SSD1306_BLACK, 1);
+    } else {
+      oled_.drawChar(x, y, '?', SSD1306_WHITE, SSD1306_BLACK, 1);
+    }
+    x += CyrillicFont::ADVANCE;
  }
 }

 void Display::show(const char *a, const char *b, uint32_t progress, uint32_t progressTotal) {
-  char one[32], two[32];
+  char one[64], two[64];
  snprintf(one, sizeof(one), "%s", a ? a : ""); snprintf(two, sizeof(two), "%s", b ? b : "");
  // Serial is the primary UI mirror and remains available when OLED is absent.
  Log::printf("UI", "%s | %s", one, two);
  if (!ok_) return;
-  fit(one); fit(two);
-  oled_.clearDisplay(); oled_.setCursor(0, 3); oled_.print(one);
-  oled_.setCursor(0, 19); oled_.print(two);
+  setPower(true);
+  oled_.clearDisplay();
+  drawTextLine(one, 3);
+  drawTextLine(two, 19);
  if (progressTotal) {
    if (progress > progressTotal) progress = progressTotal;
    const uint16_t width = static_cast<uint16_t>(
@@ -81,7 +120,8 @@ void Display::formatTestFrequency(uint32_t hz, char *out, size_t n) {
 }

 void Display::formatDuration(uint64_t us, char *out, size_t n) {
-  const uint64_t minutes = us / 60000000ULL;
-  if (minutes < 60) snprintf(out, n, "%02llu:%02llu", minutes, (us / 1000000ULL) % 60ULL);
+  const uint64_t totalSeconds = (us + 999999ULL) / 1000000ULL;
+  const uint64_t minutes = totalSeconds / 60ULL;
+  if (minutes < 60) snprintf(out, n, "%02llu:%02llu", minutes, totalSeconds % 60ULL);
  else snprintf(out, n, "%llu:%02llu", minutes / 60ULL, minutes % 60ULL);
 }
--- a/OpticalChannelTester/Display.h
+++ b/OpticalChannelTester/Display.h
@@ -9,12 +9,15 @@ class Display {
  bool begin();
  void show(const char *line1, const char *line2,
            uint32_t progress = 0, uint32_t progressTotal = 0);
+  void setPower(bool enabled);
  bool available() const { return ok_; }
+  bool powered() const { return powered_; }
  static void formatFrequency(float hz, char *out, size_t size);
  static void formatTestFrequency(uint32_t hz, char *out, size_t size);
-  static void formatDuration(uint64_t us, char *out, size_t size);
+ static void formatDuration(uint64_t us, char *out, size_t size);
 private:
-  void fit(char *text);
+  void drawTextLine(const char *text, int16_t y);
  Adafruit_SSD1306 oled_;
  bool ok_ = false;
+  bool powered_ = false;
 };
--- a/OpticalChannelTester/Font_Cyrillic.h
+++ b/OpticalChannelTester/Font_Cyrillic.h
@@ -0,0 +1,57 @@
+#pragma once
+
+#include <Arduino.h>
+
+// Compact 5x7 uppercase Cyrillic font. Lowercase UTF-8 letters are deliberately
+// rendered with the same uppercase glyphs: at 5x7 pixels this is considerably
+// clearer than trying to preserve lowercase shapes.
+namespace CyrillicFont {
+
+constexpr uint8_t WIDTH = 5;
+constexpr uint8_t HEIGHT = 7;
+constexpr uint8_t ADVANCE = 6;
+
+// Rows are stored top-to-bottom; the low five bits are pixels left-to-right.
+const uint8_t GLYPHS[][HEIGHT] PROGMEM = {
+  {0x0E, 0x11, 0x11, 0x1F, 0x11, 0x11, 0x11}, // А
+  {0x1F, 0x10, 0x10, 0x1E, 0x11, 0x11, 0x1E}, // Б
+  {0x1E, 0x11, 0x11, 0x1E, 0x11, 0x11, 0x1E}, // В
+  {0x1F, 0x10, 0x10, 0x10, 0x10, 0x10, 0x10}, // Г
+  {0x0E, 0x0A, 0x0A, 0x0A, 0x11, 0x1F, 0x11}, // Д
+  {0x1F, 0x10, 0x10, 0x1E, 0x10, 0x10, 0x1F}, // Е
+  {0x15, 0x15, 0x0E, 0x04, 0x0E, 0x15, 0x15}, // Ж
+  {0x0E, 0x11, 0x01, 0x06, 0x01, 0x11, 0x0E}, // З
+  {0x11, 0x13, 0x15, 0x15, 0x19, 0x11, 0x11}, // И
+  {0x0A, 0x11, 0x13, 0x15, 0x19, 0x11, 0x11}, // Й
+  {0x11, 0x12, 0x14, 0x18, 0x14, 0x12, 0x11}, // К
+  {0x07, 0x09, 0x09, 0x09, 0x11, 0x11, 0x11}, // Л
+  {0x11, 0x1B, 0x15, 0x15, 0x11, 0x11, 0x11}, // М
+  {0x11, 0x11, 0x11, 0x1F, 0x11, 0x11, 0x11}, // Н
+  {0x0E, 0x11, 0x11, 0x11, 0x11, 0x11, 0x0E}, // О
+  {0x1F, 0x11, 0x11, 0x11, 0x11, 0x11, 0x11}, // П
+  {0x1E, 0x11, 0x11, 0x1E, 0x10, 0x10, 0x10}, // Р
+  {0x0F, 0x10, 0x10, 0x10, 0x10, 0x10, 0x0F}, // С
+  {0x1F, 0x04, 0x04, 0x04, 0x04, 0x04, 0x04}, // Т
+  {0x11, 0x11, 0x11, 0x0F, 0x01, 0x11, 0x0E}, // У
+  {0x04, 0x0E, 0x15, 0x15, 0x0E, 0x04, 0x04}, // Ф
+  {0x11, 0x11, 0x0A, 0x04, 0x0A, 0x11, 0x11}, // Х
+  {0x12, 0x12, 0x12, 0x12, 0x12, 0x1E, 0x01}, // Ц
+  {0x11, 0x11, 0x11, 0x0F, 0x01, 0x01, 0x01}, // Ч
+  {0x15, 0x15, 0x15, 0x15, 0x15, 0x15, 0x1F}, // Ш
+  {0x15, 0x15, 0x15, 0x15, 0x15, 0x1E, 0x01}, // Щ
+  {0x18, 0x08, 0x08, 0x0E, 0x09, 0x09, 0x0E}, // Ъ
+  {0x11, 0x11, 0x11, 0x1D, 0x15, 0x15, 0x1D}, // Ы
+  {0x10, 0x10, 0x10, 0x1E, 0x11, 0x11, 0x1E}, // Ь
+  {0x0E, 0x11, 0x01, 0x07, 0x01, 0x11, 0x0E}, // Э
+  {0x12, 0x15, 0x15, 0x1D, 0x15, 0x15, 0x12}, // Ю
+  {0x0F, 0x11, 0x11, 0x0F, 0x05, 0x09, 0x11}  // Я
+};
+
+inline const uint8_t *glyph(uint32_t codepoint) {
+  if (codepoint >= 0x0430U && codepoint <= 0x044FU) codepoint -= 0x20U;
+  if (codepoint == 0x0401U || codepoint == 0x0451U) codepoint = 0x0415U; // Ё -> Е
+  if (codepoint < 0x0410U || codepoint > 0x042FU) return nullptr;
+  return GLYPHS[codepoint - 0x0410U];
+}
+
+}  // namespace CyrillicFont
--- a/OpticalChannelTester/Measurement.cpp
+++ b/OpticalChannelTester/Measurement.cpp
@@ -3,24 +3,26 @@
 #include <string.h>

 bool Measurement::start(float hz, float duty, float tolerance, uint32_t timeMs,
-                        uint8_t repeats, uint8_t settleCycles) {
+                        uint8_t settleCycles) {
  if (!task_ && xTaskCreate(taskEntry, "optical-rx", 4096, this, 4, &task_) != pdPASS) return false;
  expectedHz_ = static_cast<uint32_t>(hz + 0.5f);
-  if (!expectedHz_ || !timeMs || !repeats || repeats > 10 ||
-      !makePeriodLimits(expectedHz_, duty, tolerance, receiver_.tickHz(), limits_) ||
-      !receiver_.start(expectedHz_)) return false;
-  repeats_ = repeats; settleCycles_ = settleCycles; settleLeft_ = settleCycles;
+  expectedDutyPct_ = duty;
+  tolerance = effectiveTolerancePct(tolerance);
+  if (!expectedHz_ || !timeMs ||
+      !receiver_.start(expectedHz_, expectedDutyPct_)) return false;
+  if (!makePeriodLimits(expectedHz_, duty, tolerance, receiver_.tickHz(), limits_)) {
+    receiver_.stop(); return false;
+  }
+  settleCycles_ = settleCycles; settleLeft_ = settleCycles;
  stepTimeMs_ = (timeMs + MEASUREMENT_PROGRESS_STEPS - 1U) / MEASUREMENT_PROGRESS_STEPS;
  stepTicks_ = static_cast<uint64_t>(receiver_.tickHz()) * timeMs /
    (1000ULL * MEASUREMENT_PROGRESS_STEPS);
  if (!stepTicks_) stepTicks_ = 1;
-  totalSteps_ = repeats * MEASUREMENT_PROGRESS_STEPS;
-  currentStep_ = currentRepeat_ = 0;
-  stats_.reset(); memset(repeatPeriods_, 0, sizeof(repeatPeriods_));
+  currentStep_ = 0;
+  stats_.reset();
  publishStats();
  measurementStartTick_ = deadlineTick_ = 0; startedMs_ = millis();
  measurementStartMs_ = lastPeriodMs_ = 0;
-  currentRepeat_ = 0;
  expectedPeriodMs_ = static_cast<uint32_t>((1000ULL + expectedHz_ - 1U) / expectedHz_);
  if (!expectedPeriodMs_) expectedPeriodMs_ = 1;
  state_ = MeasureState::SETTLING;
@@ -45,18 +47,17 @@ void Measurement::fail(FailReason reason) {
  receiver_.stop(); state_ = MeasureState::FAIL;
 }

-void Measurement::completeStep() {
+void Measurement::completeMeasurement() {
  receiver_.stop();
  stats_.droppedItems += receiver_.takeDroppedItems();
  if (receiver_.overflowed()) { fail(FailReason::GLITCH); return; }
-  ++currentStep_;
  publishStats();
-  if (currentStep_ < totalSteps_) {
+  if (++currentStep_ < MEASUREMENT_PROGRESS_STEPS) {
    state_ = MeasureState::STEP_READY;
    return;
  }
-  for (uint8_t i = 0; i < repeats_; ++i) if (!repeatPeriods_[i]) {
-    fail(FailReason::TOO_FEW_PERIODS); return;
+  if (!stats_.periods) {
+    fail(FailReason::DATA_LOSS); return;
  }
  state_ = MeasureState::PASS;
 }
@@ -91,16 +92,14 @@ MeasureState Measurement::processOnce() {
        if (!settleLeft_) {
          measurementStartTick_ = period.startTick + period.periodTicks;
          deadlineTick_ = measurementStartTick_ + stepTicks_;
-          currentRepeat_ = currentStep_ / MEASUREMENT_PROGRESS_STEPS;
          measurementStartMs_ = lastPeriodMs_ = millis(); state_ = MeasureState::RUNNING;
        }
        continue;
      }
      const uint64_t endTick = period.startTick + period.periodTicks;
      if (period.startTick < measurementStartTick_) continue; // leading incomplete period
-      if (endTick > deadlineTick_) { completeStep(); return state_; } // trailing incomplete period
-      ++repeatPeriods_[currentRepeat_];
-      const FailReason r = evaluatePeriodFast(period, receiver_.tickHz(), limits_, currentRepeat_ + 1, stats_);
+      if (endTick > deadlineTick_) { completeMeasurement(); return state_; } // trailing incomplete period
+      const FailReason r = evaluatePeriodFast(period, receiver_.tickHz(), limits_, 1, stats_);
      if (r != FailReason::NONE) { fail(r); return state_; }
    }
  }
@@ -113,11 +112,18 @@ MeasureState Measurement::processOnce() {
  if (state_ == MeasureState::SETTLING && millis() - startedMs_ > settleTimeout) fail(FailReason::NO_SIGNAL);
  if (state_ == MeasureState::RUNNING && measurementStartTick_) {
    const uint32_t now = millis();
-    const uint32_t edgeTimeoutMs = expectedPeriodMs_ * NO_SIGNAL_TIMEOUT_PERIODS + 2;
-    if (now - measurementStartMs_ < stepTimeMs_ && now - lastPeriodMs_ > edgeTimeoutMs) {
+    // RMT reports a block only after its user buffer has filled. At 1 kHz the
+    // minimum 48-symbol C3 block contains roughly 48 PWM periods and therefore
+    // arrives much later than the old 8-period timeout. Do not call that
+    // normal batching delay a lost edge.
+    const uint32_t batchPeriods = receiver_.receiveChunkSymbols();
+    const uint32_t batchTimeoutMs = expectedPeriodMs_ * (batchPeriods + NO_SIGNAL_TIMEOUT_PERIODS) + 2U;
+    const uint32_t edgeTimeoutMs = expectedPeriodMs_ * NO_SIGNAL_TIMEOUT_PERIODS + 2U;
+    const uint32_t receiveTimeoutMs = batchTimeoutMs > edgeTimeoutMs ? batchTimeoutMs : edgeTimeoutMs;
+    if (now - measurementStartMs_ < stepTimeMs_ && now - lastPeriodMs_ > receiveTimeoutMs) {
      fail(FailReason::LOST_EDGE); return state_;
    }
-    if (now - measurementStartMs_ > stepTimeMs_ + expectedPeriodMs_ + 2) completeStep();
+    if (now - measurementStartMs_ > stepTimeMs_ + expectedPeriodMs_ + 2) completeMeasurement();
  }
  return state_;
 }
@@ -126,7 +132,7 @@ MeasureState Measurement::update() { return state_; }

 bool Measurement::continueAfterDisplay() {
  if (state_ != MeasureState::STEP_READY) return false;
-  if (!receiver_.start(expectedHz_)) {
+  if (!receiver_.start(expectedHz_, expectedDutyPct_)) {
    fail(FailReason::UNSUPPORTED);
    return false;
  }
--- a/OpticalChannelTester/Measurement.h
+++ b/OpticalChannelTester/Measurement.h
@@ -7,20 +7,21 @@ class Measurement {
 public:
  explicit Measurement(PulseReceiver &receiver) : receiver_(receiver) {}
  bool start(float expectedHz, float expectedDuty, float tolerancePct,
-             uint32_t testTimeMs, uint8_t repeats, uint8_t settleCycles);
+             uint32_t testTimeMs, uint8_t settleCycles);
  MeasureState update();
  bool continueAfterDisplay();
  void abort();
  MeasureState state() const { return state_; }
  FailReason reason() const { return stats_.reason; }
  const StageStats &stats() const { return stats_; }
+  uint8_t progressStep() const { return currentStep_; }
  bool statsSnapshot(StageStats &out) const;
 private:
  static void taskEntry(void *context);
  void taskLoop();
  MeasureState processOnce();
  void fail(FailReason reason);
-  void completeStep();
+  void completeMeasurement();
  void publishStats();
  PulseReceiver &receiver_;
  volatile MeasureState state_ = MeasureState::IDLE;
@@ -30,11 +31,11 @@ class Measurement {
  mutable portMUX_TYPE statsMux_ = portMUX_INITIALIZER_UNLOCKED;
  PeriodLimits limits_ = {};
  uint32_t expectedHz_ = 0;
-  uint8_t repeats_ = 0, settleCycles_ = 0, settleLeft_ = 0;
-  uint8_t currentRepeat_ = 0, currentStep_ = 0, totalSteps_ = 0;
+  float expectedDutyPct_ = 0.0f;
+  uint8_t settleCycles_ = 0, settleLeft_ = 0;
  uint64_t measurementStartTick_ = 0, deadlineTick_ = 0, stepTicks_ = 0;
  uint32_t startedMs_ = 0, measurementStartMs_ = 0, lastPeriodMs_ = 0;
  uint32_t stepTimeMs_ = 1, expectedPeriodMs_ = 1;
-  uint32_t repeatPeriods_[10] = {};
+  volatile uint8_t currentStep_ = 0;
  PulsePeriod periodBatch_[PERIOD_BATCH_SIZE] = {};
 };
--- a/OpticalChannelTester/Protocol.h
+++ b/OpticalChannelTester/Protocol.h
@@ -2,7 +2,7 @@
 #include "Core.h"

 constexpr uint16_t PROTOCOL_MAGIC = 0x4F43;
-constexpr uint8_t PROTOCOL_VERSION = 6;
+constexpr uint8_t PROTOCOL_VERSION = 8;

 enum class MessageType : uint8_t {
  DISCOVER, DISCOVER_ACK, PREPARE, READY, START_STAGE, RESULT, ACK, ABORT,
@@ -24,9 +24,9 @@ struct ProtocolPacket {
  uint32_t actualHz;
  uint16_t actualDutyX100;
  uint32_t testTimeMs;
-  uint8_t repeats;
  uint16_t accuracyX100;
  uint8_t settleCycles;
+  uint8_t progressStep;
  uint8_t passed;
  uint8_t reason;
  uint32_t periods;
--- a/OpticalChannelTester/Pwm.cpp
+++ b/OpticalChannelTester/Pwm.cpp
@@ -1,9 +1,14 @@
 #include "Pwm.h"
 #include "Config.h"
 #include "Core.h"
+#if CONFIG_IDF_TARGET_ESP32C3
 #include <hal/ledc_ll.h>
+#elif CONFIG_IDF_TARGET_ESP32S3
+#include <driver/mcpwm_prelude.h>
+#endif

 namespace {
+#if CONFIG_IDF_TARGET_ESP32C3
 constexpr ledc_mode_t PWM_SPEED_MODE = LEDC_LOW_SPEED_MODE;
 constexpr ledc_timer_t PWM_TIMER = LEDC_TIMER_0;

@@ -22,16 +27,90 @@ bool integerDividerIsSet(uint16_t expected) {
  ledc_ll_get_clock_divider(LEDC_LL_GET_HW(), PWM_SPEED_MODE, PWM_TIMER, &rawDivider);
  return rawDivider == (static_cast<uint32_t>(expected) << LEDC_LL_FRACTIONAL_BITS);
 }
+#elif CONFIG_IDF_TARGET_ESP32S3
+mcpwm_timer_handle_t mcpwmTimer = nullptr;
+mcpwm_oper_handle_t mcpwmOperator = nullptr;
+mcpwm_cmpr_handle_t mcpwmComparator = nullptr;
+mcpwm_gen_handle_t mcpwmGenerator = nullptr;
+uint32_t mcpwmFrequencyHz = 0;
+
+void releaseMcpwm() {
+  if (mcpwmGenerator) {
+    mcpwm_del_generator(mcpwmGenerator);
+    mcpwmGenerator = nullptr;
+  }
+  if (mcpwmComparator) {
+    mcpwm_del_comparator(mcpwmComparator);
+    mcpwmComparator = nullptr;
+  }
+  if (mcpwmOperator) {
+    mcpwm_del_operator(mcpwmOperator);
+    mcpwmOperator = nullptr;
+  }
+  if (mcpwmTimer) {
+    mcpwm_timer_disable(mcpwmTimer);
+    mcpwm_del_timer(mcpwmTimer);
+    mcpwmTimer = nullptr;
+  }
+}
+
+uint8_t periodResolutionBits(uint32_t periodTicks) {
+  uint8_t bits = 0;
+  while (periodTicks > 1U) {
+    periodTicks >>= 1U;
+    ++bits;
+  }
+  return bits ? bits : 1U;
+}
+#endif
 }

 void PwmGenerator::begin() {
+#if CONFIG_IDF_TARGET_ESP32C3
  // Match LEDC_SOURCE_CLOCK_HZ and make the timer calculation deterministic.
  ledcSetClockSource(LEDC_USE_XTAL_CLK);
  pinMode(GPIO_PWM, OUTPUT);
  stop();
+#elif CONFIG_IDF_TARGET_ESP32S3
+  mcpwm_timer_config_t timerConfig = {};
+  timerConfig.group_id = 0;
+  timerConfig.clk_src = MCPWM_TIMER_CLK_SRC_PLL160M;
+  timerConfig.resolution_hz = MCPWM_RESOLUTION_HZ;
+  timerConfig.count_mode = MCPWM_TIMER_COUNT_MODE_UP;
+  timerConfig.period_ticks = MCPWM_RESOLUTION_HZ / 1000U;
+
+  mcpwm_operator_config_t operatorConfig = {};
+  operatorConfig.group_id = 0;
+  mcpwm_comparator_config_t comparatorConfig = {};
+  mcpwm_generator_config_t generatorConfig = {};
+  generatorConfig.gen_gpio_num = GPIO_PWM;
+
+  bool ok = mcpwm_new_timer(&timerConfig, &mcpwmTimer) == ESP_OK;
+  ok = ok && mcpwm_new_operator(&operatorConfig, &mcpwmOperator) == ESP_OK;
+  ok = ok && mcpwm_operator_connect_timer(mcpwmOperator, mcpwmTimer) == ESP_OK;
+  ok = ok && mcpwm_new_comparator(mcpwmOperator, &comparatorConfig, &mcpwmComparator) == ESP_OK;
+  ok = ok && mcpwm_new_generator(mcpwmOperator, &generatorConfig, &mcpwmGenerator) == ESP_OK;
+  ok = ok && mcpwm_comparator_set_compare_value(mcpwmComparator,
+    timerConfig.period_ticks / 2U) == ESP_OK;
+  ok = ok && mcpwm_generator_set_action_on_timer_event(mcpwmGenerator,
+    MCPWM_GEN_TIMER_EVENT_ACTION(MCPWM_TIMER_DIRECTION_UP,
+      MCPWM_TIMER_EVENT_EMPTY, MCPWM_GEN_ACTION_HIGH)) == ESP_OK;
+  ok = ok && mcpwm_generator_set_action_on_compare_event(mcpwmGenerator,
+    MCPWM_GEN_COMPARE_EVENT_ACTION(MCPWM_TIMER_DIRECTION_UP,
+      mcpwmComparator, MCPWM_GEN_ACTION_LOW)) == ESP_OK;
+  ok = ok && mcpwm_timer_enable(mcpwmTimer) == ESP_OK;
+  if (!ok) {
+    releaseMcpwm();
+    pinMode(GPIO_PWM, OUTPUT);
+    digitalWrite(GPIO_PWM, PWM_SAFE_LEVEL);
+    return;
+  }
+  mcpwm_generator_set_force_level(mcpwmGenerator, PWM_SAFE_LEVEL, true);
+#endif
 }

 bool PwmGenerator::start(uint32_t hz, uint8_t dutyPct, ActualPwm &a) {
+#if CONFIG_IDF_TARGET_ESP32C3
  IntegerPwmConfig config = {};
  if (!chooseIntegerPwmConfig(hz, LEDC_SOURCE_CLOCK_HZ, LEDC_MAX_BITS, dutyPct, config)) return false;
  const uint8_t bits = config.bits;
@@ -64,10 +143,44 @@ bool PwmGenerator::start(uint32_t hz, uint8_t dutyPct, ActualPwm &a) {
  }
  pinMode(GPIO_PWM, OUTPUT); digitalWrite(GPIO_PWM, PWM_SAFE_LEVEL);
  return false;
+#elif CONFIG_IDF_TARGET_ESP32S3
+  if (!mcpwmTimer || !mcpwmComparator || !mcpwmGenerator || !hz || dutyPct > 100U ||
+      MCPWM_RESOLUTION_HZ % hz) return false;
+  const uint32_t periodTicks = MCPWM_RESOLUTION_HZ / hz;
+  if (periodTicks < 2U || periodTicks > MCPWM_MAX_PERIOD_TICKS) return false;
+  uint32_t activeTicks = (static_cast<uint64_t>(periodTicks) * dutyPct + 50U) / 100U;
+  if (activeTicks == 0U) activeTicks = 1U;
+  if (activeTicks >= periodTicks) activeTicks = periodTicks - 1U;
+
+  stop();
+  bool ok = mcpwm_timer_set_period(mcpwmTimer, periodTicks) == ESP_OK;
+  ok = ok && mcpwm_comparator_set_compare_value(mcpwmComparator, activeTicks) == ESP_OK;
+  ok = ok && mcpwm_generator_set_force_level(mcpwmGenerator, -1, false) == ESP_OK;
+  ok = ok && mcpwm_timer_start_stop(mcpwmTimer, MCPWM_TIMER_START_NO_STOP) == ESP_OK;
+  if (!ok) {
+    mcpwm_generator_set_force_level(mcpwmGenerator, PWM_SAFE_LEVEL, true);
+    return false;
+  }
+
+  a = {hz, hz, 100.0f * activeTicks / periodTicks, periodResolutionBits(periodTicks)};
+  mcpwmFrequencyHz = hz;
+  running_ = true;
+  return true;
+#endif
 }

 void PwmGenerator::stop() {
+#if CONFIG_IDF_TARGET_ESP32C3
  if (running_) ledcDetach(GPIO_PWM);
  pinMode(GPIO_PWM, OUTPUT); digitalWrite(GPIO_PWM, PWM_SAFE_LEVEL);
+#elif CONFIG_IDF_TARGET_ESP32S3
+  if (mcpwmGenerator) mcpwm_generator_set_force_level(mcpwmGenerator, PWM_SAFE_LEVEL, true);
+  if (running_ && mcpwmTimer) {
+    mcpwm_timer_start_stop(mcpwmTimer, MCPWM_TIMER_STOP_EMPTY);
+    const uint32_t waitUs = mcpwmFrequencyHz ? (1000000U / mcpwmFrequencyHz + 2U) : 2U;
+    delayMicroseconds(waitUs);
+  }
+  mcpwmFrequencyHz = 0;
+#endif
  running_ = false;
 }
--- a/OpticalChannelTester/Radio.cpp
+++ b/OpticalChannelTester/Radio.cpp
@@ -55,9 +55,39 @@ void Radio::end() {
  if (queue_) xQueueReset(queue_);
  if (heartbeatQueue_) xQueueReset(heartbeatQueue_);
  if (instance_ == this) instance_ = nullptr;
+  windowedReceive_ = false;
  Log::event("ESP-NOW", "stopped");
 }

+bool Radio::setWindowedReceive(bool enabled) {
+  if (!active_) return false;
+  if (windowedReceive_ == enabled) return true;
+
+  const uint16_t window = enabled ? SLAVE_LISTEN_WINDOW_MS : UINT16_MAX;
+  const uint16_t interval = enabled ? SLAVE_LISTEN_INTERVAL_MS :
+    ESP_WIFI_CONNECTIONLESS_INTERVAL_DEFAULT_MODE;
+  const esp_err_t windowResult = esp_now_set_wake_window(window);
+  const esp_err_t intervalResult = esp_wifi_connectionless_module_set_wake_interval(interval);
+  const bool sleepResult = WiFi.setSleep(enabled);
+  const bool ok = windowResult == ESP_OK && intervalResult == ESP_OK && sleepResult;
+
+  bool continuousRestored = true;
+  if (!ok) {
+    continuousRestored = esp_now_set_wake_window(UINT16_MAX) == ESP_OK;
+    continuousRestored =
+      esp_wifi_connectionless_module_set_wake_interval(
+        ESP_WIFI_CONNECTIONLESS_INTERVAL_DEFAULT_MODE) == ESP_OK && continuousRestored;
+    continuousRestored = WiFi.setSleep(false) && continuousRestored;
+    windowedReceive_ = false;
+  } else windowedReceive_ = enabled;
+
+  Log::printf("ESP-NOW", "RX power-save %s window=%ums interval=%ums %s%s",
+    enabled ? "ON" : "OFF", window, interval,
+    ok ? "OK" : "FAILED; continuous RX restore ",
+    ok ? "" : (continuousRestored ? "OK" : "FAILED"));
+  return ok;
+}
+
 bool Radio::ensurePeer(const uint8_t mac[6]) {
  if (esp_now_is_peer_exist(mac)) return true;
  esp_now_peer_info_t peer = {};
@@ -80,7 +110,8 @@ bool Radio::sendTo(const uint8_t mac[6], ProtocolPacket p) {
  finalizePacket(p);
  const bool ok = esp_now_send(mac, reinterpret_cast<const uint8_t *>(&p), sizeof(p)) == ESP_OK;
  const MessageType type = static_cast<MessageType>(p.type);
-  if (type != MessageType::HEARTBEAT && type != MessageType::HEARTBEAT_ACK && type != MessageType::PROGRESS)
+  if (type != MessageType::DISCOVER && type != MessageType::HEARTBEAT &&
+      type != MessageType::HEARTBEAT_ACK && type != MessageType::PROGRESS)
    Log::printf("ESP-NOW", "TX %s to %s session=%08lX stage=%u seq=%u %s",
      messageName(type), peer, p.session, p.stage, p.sequence, ok ? "QUEUED" : "FAILED");
  return ok;
--- a/OpticalChannelTester/Radio.h
+++ b/OpticalChannelTester/Radio.h
@@ -12,6 +12,7 @@ class Radio {
  bool sendBroadcast(ProtocolPacket packet);
  bool sendTo(const uint8_t mac[6], ProtocolPacket packet);
  bool receive(ReceivedPacket &received);
+  bool setWindowedReceive(bool enabled);
  void flush();
  uint32_t lastReceiveMs() const { return __atomic_load_n(&lastValidRxMs_, __ATOMIC_RELAXED); }
  static void macText(const uint8_t mac[6], char *out, size_t size);
@@ -28,5 +29,6 @@ class Radio {
  volatile bool active_ = false;
  volatile uint32_t lastValidRxMs_ = 0;
  uint32_t lastChannelCheckMs_ = 0;
+  bool windowedReceive_ = false;
 };

--- a/OpticalChannelTester/Receiver.cpp
+++ b/OpticalChannelTester/Receiver.cpp
@@ -8,17 +8,55 @@

 uint32_t PulseReceiver::tickHz() const {
 #if OPTICAL_USE_RMT_DMA
-  return CAPTURE_RESOLUTION_HZ;
+  return captureResolutionHz_;
 #else
  return cpuTickHz_;
 #endif
 }

+uint32_t PulseReceiver::plannedTickHz(uint32_t expectedHz, float expectedDutyPct) const {
+#if OPTICAL_USE_RMT_DMA
+  if (!expectedHz || expectedDutyPct <= 0.0f || expectedDutyPct >= 100.0f)
+    return CAPTURE_RESOLUTION_OPTIONS_HZ[0];
+  uint32_t dutyX100 = static_cast<uint32_t>(expectedDutyPct * 100.0f + 0.5f);
+  if (dutyX100 < 5000U) dutyX100 = 10000U - dutyX100;
+  for (int i = static_cast<int>(countOf(CAPTURE_RESOLUTION_OPTIONS_HZ)) - 1; i >= 0; --i) {
+    const uint32_t resolution = CAPTURE_RESOLUTION_OPTIONS_HZ[i];
+    const uint64_t levelTicksX100 = static_cast<uint64_t>(resolution) * dutyX100;
+    const uint64_t limitX100 = static_cast<uint64_t>(expectedHz) * 10000ULL * RMT_MAX_LEVEL_TICKS;
+    if (levelTicksX100 <= limitX100) return resolution;
+  }
+  return CAPTURE_RESOLUTION_OPTIONS_HZ[0];
+#else
+  (void)expectedHz; (void)expectedDutyPct;
+  return cpuTickHz_;
+#endif
+}
+
 bool PulseReceiver::begin() {
 #if OPTICAL_USE_RMT_DMA
  queue_ = xQueueCreate(RMT_QUEUE_BLOCKS, sizeof(SymbolBlock));
+  return queue_ && configureRmt(CAPTURE_RESOLUTION_OPTIONS_HZ[0]);
+#else
+  queue_ = xQueueCreate(256, sizeof(Edge));
+  if (!queue_) return false;
+  pinMode(GPIO_RX, INPUT);
+  cpuTickHz_ = getCpuFrequencyMhz() * 1000000UL;
+  attachInterruptArg(GPIO_RX, onGpio, this, CHANGE);
+  return cpuTickHz_ != 0;
+#endif
+}
+
+#if OPTICAL_USE_RMT_DMA
+bool PulseReceiver::configureRmt(uint32_t resolutionHz) {
+  if (channel_ && captureResolutionHz_ == resolutionHz) return true;
+  stop();
+  if (channel_) {
+    if (rmt_del_channel(channel_) != ESP_OK) return false;
+    channel_ = nullptr;
+  }
  rmt_rx_channel_config_t cfg = {};
-  cfg.clk_src = RMT_CLK_SRC_DEFAULT; cfg.resolution_hz = CAPTURE_RESOLUTION_HZ;
+  cfg.clk_src = RMT_CLK_SRC_DEFAULT; cfg.resolution_hz = resolutionHz;
  cfg.gpio_num = static_cast<gpio_num_t>(GPIO_RX);
  cfg.flags.invert_in = RX_SIGNAL_INVERTED;
 #if CONFIG_IDF_TARGET_ESP32S3
@@ -30,20 +68,23 @@ bool PulseReceiver::begin() {
  cfg.mem_block_symbols = RMT_MIN_RECEIVE_SYMBOLS;
  cfg.flags.with_dma = false; // C3 uses hardware RMT ping-pong partial reception
 #endif
-  if (!queue_ || rmt_new_rx_channel(&cfg, &channel_) != ESP_OK) return false;
+  if (rmt_new_rx_channel(&cfg, &channel_) != ESP_OK) return false;
  rmt_rx_event_callbacks_t callbacks = {}; callbacks.on_recv_done = onRmt;
-  return rmt_rx_register_event_callbacks(channel_, &callbacks, this) == ESP_OK;
-#else
-  queue_ = xQueueCreate(256, sizeof(Edge));
-  if (!queue_) return false;
-  pinMode(GPIO_RX, INPUT);
-  cpuTickHz_ = getCpuFrequencyMhz() * 1000000UL;
-  attachInterruptArg(GPIO_RX, onGpio, this, CHANGE);
-  return cpuTickHz_ != 0;
-#endif
+  if (rmt_rx_register_event_callbacks(channel_, &callbacks, this) != ESP_OK) {
+    rmt_del_channel(channel_); channel_ = nullptr; return false;
+  }
+  captureResolutionHz_ = resolutionHz;
+  return true;
 }
+#endif

-bool PulseReceiver::start(uint32_t expectedHz) {
+bool PulseReceiver::start(uint32_t expectedHz, float expectedDutyPct) {
+#if OPTICAL_USE_RMT_DMA
+  const uint32_t resolutionHz = plannedTickHz(expectedHz, expectedDutyPct);
+  if (!configureRmt(resolutionHz)) return false;
+#else
+  (void)expectedHz; (void)expectedDutyPct;
+#endif
  resetStream();
 #if OPTICAL_USE_RMT_DMA
  // In partial RX mode the callback is delivered when this user buffer fills.
@@ -54,19 +95,17 @@ bool PulseReceiver::start(uint32_t expectedHz) {
  receiveChunkSymbols_ = static_cast<uint16_t>(symbols);
  if (rmt_enable(channel_) != ESP_OK) return false;
  rmt_receive_config_t cfg = {};
-  cfg.signal_range_min_ns = 1000000000UL / CAPTURE_RESOLUTION_HZ;
+  cfg.signal_range_min_ns = 1000000000UL / captureResolutionHz_;
  const uint64_t maxNs = 4000000000ULL / (expectedHz ? expectedHz : 1);
  // A duration field is 15 bits. Keep the driver's end-of-signal threshold
  // strictly below that hardware limit (IDF rejects larger values).
-  const uint64_t hardwareMaxNs = 32766ULL * 1000000000ULL / CAPTURE_RESOLUTION_HZ;
+  const uint64_t hardwareMaxNs = static_cast<uint64_t>(RMT_MAX_LEVEL_TICKS) * 1000000000ULL / captureResolutionHz_;
  cfg.signal_range_max_ns = static_cast<uint32_t>(maxNs > hardwareMaxNs ? hardwareMaxNs : maxNs);
  cfg.flags.en_partial_rx = true;
  if (rmt_receive(channel_, receiveBuffer_,
                  receiveChunkSymbols_ * sizeof(receiveBuffer_[0]), &cfg) != ESP_OK) {
    rmt_disable(channel_); return false;
  }
-#else
-  (void)expectedHz;
 #endif
  running_ = true; return true;
 }
--- a/OpticalChannelTester/Receiver.h
+++ b/OpticalChannelTester/Receiver.h
@@ -15,13 +15,14 @@
 class PulseReceiver {
 public:
  bool begin();
-  bool start(uint32_t expectedHz);
+  bool start(uint32_t expectedHz, float expectedDutyPct);
  void stop();
  void resetStream();
  size_t readPeriods(PulsePeriod *periods, size_t capacity, TickType_t waitTicks = 0);
  bool overflowed();
  uint32_t takeDroppedItems();
  uint32_t tickHz() const;
+  uint32_t plannedTickHz(uint32_t expectedHz, float expectedDutyPct) const;
  uint16_t receiveChunkSymbols() const { return receiveChunkSymbols_; }
  bool highRateBackend() const {
 #if OPTICAL_USE_RMT_DMA && CONFIG_IDF_TARGET_ESP32S3
@@ -38,8 +39,10 @@ class PulseReceiver {
  static constexpr size_t BLOCK_SYMBOLS = RMT_MAX_RECEIVE_SYMBOLS;
  struct SymbolBlock { uint16_t count; rmt_symbol_word_t symbols[BLOCK_SYMBOLS]; };
  static bool IRAM_ATTR onRmt(rmt_channel_handle_t, const rmt_rx_done_event_data_t *, void *);
+  bool configureRmt(uint32_t resolutionHz);
  bool nextRmtEdge(Edge &edge, TickType_t waitTicks);
  rmt_channel_handle_t channel_ = nullptr;
+  uint32_t captureResolutionHz_ = 0;
  rmt_symbol_word_t receiveBuffer_[RMT_MAX_RECEIVE_SYMBOLS];
  uint16_t receiveChunkSymbols_ = 0;
  SymbolBlock isrBlock_ = {};
--- a/OpticalChannelTester/SettingsStore.cpp
+++ b/OpticalChannelTester/SettingsStore.cpp
@@ -3,19 +3,19 @@
 #include "Log.h"
 #include <Preferences.h>

-namespace { constexpr uint16_t SETTINGS_VERSION = 1; constexpr char NAMESPACE[] = "opt-test"; }
+namespace { constexpr uint16_t SETTINGS_VERSION = 4; constexpr char NAMESPACE[] = "opt-test"; }

 void SettingsStore::defaults(Settings &s) const {
-  s = {SETTINGS_VERSION, static_cast<uint8_t>(Role::SOLO), 0, 4, 1, 2, 3, 2, 2, 0};
+  s = {SETTINGS_VERSION, static_cast<uint8_t>(Role::SOLO), 0, 4, 2, 3, 2, 0};
  s.checksum = settingsChecksum(s);
 }

 bool SettingsStore::valid(const Settings &s) const {
  return s.version == SETTINGS_VERSION && s.role <= static_cast<uint8_t>(Role::SLAVE) &&
    s.startIndex < countOf(START_FREQ_OPTIONS_HZ) && s.endIndex < countOf(END_FREQ_OPTIONS_HZ) &&
-    s.stepIndex < countOf(STEP_OPTIONS_HZ) && s.accuracyIndex < countOf(ACCURACY_OPTIONS_PCT) &&
-    s.timeIndex < countOf(TEST_TIME_OPTIONS_MS) && s.repeatIndex < countOf(REPEAT_OPTIONS) &&
-    s.dutyIndex < countOf(DUTY_OPTIONS_PCT) && s.checksum == settingsChecksum(s) &&
+    s.accuracyIndex < countOf(ACCURACY_OPTIONS_PCT) &&
+    s.timeIndex < countOf(TEST_TIME_OPTIONS_MS) && s.dutyIndex < countOf(DUTY_OPTIONS_PCT) &&
+    s.checksum == settingsChecksum(s) &&
    END_FREQ_OPTIONS_HZ[s.endIndex] > START_FREQ_OPTIONS_HZ[s.startIndex];
 }

@@ -40,7 +40,6 @@ bool SettingsStore::save(Settings &s) {

 TestParams SettingsStore::params(const Settings &s) const {
  return {START_FREQ_OPTIONS_HZ[s.startIndex], END_FREQ_OPTIONS_HZ[s.endIndex],
-    STEP_OPTIONS_HZ[s.stepIndex], ACCURACY_OPTIONS_PCT[s.accuracyIndex],
-    TEST_TIME_OPTIONS_MS[s.timeIndex], REPEAT_OPTIONS[s.repeatIndex],
+    ACCURACY_OPTIONS_PCT[s.accuracyIndex], TEST_TIME_OPTIONS_MS[s.timeIndex],
    DUTY_OPTIONS_PCT[s.dutyIndex]};
 }
--- a/PCB/Libs/ESP32-C3-SuperMini.PcbLib
+++ b/PCB/Libs/ESP32-C3-SuperMini.PcbLib
--- a/PCB/Libs/ESP32-C3-SuperMini.SchLib
+++ b/PCB/Libs/ESP32-C3-SuperMini.SchLib
--- a/PCB/Libs/ESP32-S3-SuperMini.PcbLib
+++ b/PCB/Libs/ESP32-S3-SuperMini.PcbLib
--- a/PCB/Libs/ESP32-S3-SuperMini.SchLib
+++ b/PCB/Libs/ESP32-S3-SuperMini.SchLib
--- a/PCB/Libs/HFBR-1528Z_HFBR-2528Z.PcbLib
+++ b/PCB/Libs/HFBR-1528Z_HFBR-2528Z.PcbLib
--- a/PCB/Libs/J_ARK2.Schlib
+++ b/PCB/Libs/J_ARK2.Schlib
--- a/PCB/Libs/J_ARK2_2.54.PcbLib
+++ b/PCB/Libs/J_ARK2_2.54.PcbLib
--- a/PCB/Libs/MOD_OLED_0.91_128x32.PcbLib
+++ b/PCB/Libs/MOD_OLED_0.91_128x32.PcbLib
--- a/PCB/Libs/MOD_OLED_0.91_128x32.SchLib
+++ b/PCB/Libs/MOD_OLED_0.91_128x32.SchLib
--- a/PCB/Libs/SN75451BP.PcbLib
+++ b/PCB/Libs/SN75451BP.PcbLib
--- a/PCB/Libs/SN75451BP.SchLib
+++ b/PCB/Libs/SN75451BP.SchLib
--- a/PCB/Libs/Sensor
+++ b/PCB/Libs/Sensor
--- a/PCB/Libs/Switch
+++ b/PCB/Libs/Switch
--- a/PCB/Libs/Switch
+++ b/PCB/Libs/Switch
--- a/PCB/OptoTest.PcbDoc
+++ b/PCB/OptoTest.PcbDoc
--- a/PCB/OptoTest.PrjPcb
+++ b/PCB/OptoTest.PrjPcb
--- a/PCB/OptoTest.PrjPcbStructure
+++ b/PCB/OptoTest.PrjPcbStructure
@@ -0,0 +1 @@
+Record=TopLevelDocument|FileName=OptoTest.SchDoc
--- a/PCB/OptoTest.SchDoc
+++ b/PCB/OptoTest.SchDoc
--- a/README.md
+++ b/README.md
Author	SHA1	Message	Date
Razvalyaev	61d3aeaba6	минор фиксы pcb	2026-08-08 20:02:14 +03:00
Razvalyaev	34581913ff	Пины и ШИМ для S3 (не проверено)	2026-08-08 19:50:34 +03:00
Razvalyaev	be1a90afac	Добавлена разведенная PCB плата	2026-08-08 19:49:35 +03:00
Razvalyaev	70fe3566b4	Сделан русский текст	2026-08-08 11:15:20 +03:00
Razvalyaev	c952c165f8	Добавлено энергосбережение для увеличения работы от аккума: - через 60 сек экран выключается и есп уходит в сон - слейв в ожидании мастера прослушивает не постоянно 20мс/100мс	2026-08-08 10:42:59 +03:00
Razvalyaev	21f8fe8e13	Улучшения - улушчено отображение на OLED - убраны настройки шага частоты и количества повторов - сделан перебор только реализуемых частот - увеличена точность, на 1МГц 1.25%, в остальных до 1% - точное измерение TOTAL TIME	2026-08-08 10:18:50 +03:00
				`@@ -0,0 +1 @@`
				`Record=TopLevelDocument\|FileName=OptoTest.SchDoc`