Fix: Lillygo Tbeam 1W Fan Control and LNA Sequencing improvements

examples/companion_radio/main.cpp

@@ -229,4 +229,7 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
+#ifdef P_FAN_CTRL
+  update_fan_control();
+#endif
 }

examples/simple_repeater/MyMesh.cpp

@@ -888,6 +888,9 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
   _prefs.flood_max = 64;
   _prefs.interference_threshold = 0; // disabled
 
+  #ifdef DEFAULT_AGC_RESET_INTERVAL
+  _prefs.agc_reset_interval = DEFAULT_AGC_RESET_INTERVAL;
+  #endif
   // bridge defaults
   _prefs.bridge_enabled = 1;    // enabled
   _prefs.bridge_delay   = 500;  // milliseconds

examples/simple_repeater/main.cpp

@@ -153,7 +153,9 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
-
+  #ifdef P_FAN_CTRL
+  update_fan_control();
+  #endif
   if (the_mesh.getNodePrefs()->powersaving_enabled && !the_mesh.hasPendingWork()) {
     #if defined(NRF52_PLATFORM)
     board.sleep(1800); // nrf ignores seconds param, sleeps whenever possible

examples/simple_room_server/MyMesh.cpp

@@ -644,6 +644,9 @@ MyMesh::MyMesh(mesh::MainBoard &board, mesh::Radio &radio, mesh::MillisecondCloc
   _prefs.flood_advert_interval = 12; // 12 hours
   _prefs.flood_max = 64;
   _prefs.interference_threshold = 0; // disabled
+  #ifdef DEFAULT_AGC_RESET_INTERVAL
+  _prefs.agc_reset_interval = DEFAULT_AGC_RESET_INTERVAL;
+  #endif
 #ifdef ROOM_PASSWORD
   StrHelper::strncpy(_prefs.guest_password, ROOM_PASSWORD, sizeof(_prefs.guest_password));
 #endif

examples/simple_room_server/main.cpp

@@ -113,4 +113,7 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
+#ifdef P_FAN_CTRL
+  update_fan_control();
+#endif
 }

variants/lilygo_tbeam_1w/TBeam1WBoard.cpp

@@ -3,30 +3,49 @@
 void TBeam1WBoard::begin() {
   ESP32Board::begin();
 
-  // Power on radio module (must be done before radio init)
+  // Power on radio module (must be done before radio init).
+  // Drive LOW first to ensure a clean SX1262 reset — on soft reboot the ESP32
+  // GPIO glitch may be too brief to drain module capacitors, leaving the SX1262
+  // in a stuck state. Holding LOW for 50ms guarantees a full power cycle.
   pinMode(SX126X_POWER_EN, OUTPUT);
+  digitalWrite(SX126X_POWER_EN, LOW);
+  delay(50);
   digitalWrite(SX126X_POWER_EN, HIGH);
   radio_powered = true;
   delay(10);  // Allow radio to power up
 
-  // RF switch RXEN pin handled by RadioLib via setRfSwitchPins()
+  // Explicitly drive RXEN HIGH (LNA on) from boot, before RadioLib takes over.
+  // Without this the pin floats until the first startReceive() call.
+  pinMode(SX126X_RXEN, OUTPUT);
+  digitalWrite(SX126X_RXEN, HIGH);
 
   // Initialize LED
   pinMode(LED_PIN, OUTPUT);
   digitalWrite(LED_PIN, LOW);
 
-  // Initialize fan control (on by default - 1W PA can overheat)
+  // Fan starts off; onAfterTransmit() enables it with a 30s cooldown timer
   pinMode(FAN_CTRL_PIN, OUTPUT);
-  digitalWrite(FAN_CTRL_PIN, HIGH);
+  digitalWrite(FAN_CTRL_PIN, LOW);
 }
 
 void TBeam1WBoard::onBeforeTransmit() {
-  // RF switching handled by RadioLib via SX126X_DIO2_AS_RF_SWITCH and setRfSwitchPins()
-  digitalWrite(LED_PIN, HIGH);  // TX LED on
+  digitalWrite(SX126X_RXEN, LOW);  // disconnect LNA before PA ramps up
+  digitalWrite(LED_PIN, HIGH);
 }
 
 void TBeam1WBoard::onAfterTransmit() {
-  digitalWrite(LED_PIN, LOW);   // TX LED off
+  digitalWrite(SX126X_RXEN, HIGH); // re-enable LNA immediately after TX
+  digitalWrite(LED_PIN, LOW);
+  // Keep fan running for 10s after TX
+  setFanEnabled(true);
+  _fan_off_millis = millis() + 10000;
+}
+
+void TBeam1WBoard::updateFan() {
+  if (_fan_off_millis > 0 && (long)(millis() - _fan_off_millis) >= 0) {
+    setFanEnabled(false);
+    _fan_off_millis = 0;
+  }
 }
 
 uint16_t TBeam1WBoard::getBattMilliVolts() {
@@ -68,4 +87,4 @@ void TBeam1WBoard::setFanEnabled(bool enabled) {
 
 bool TBeam1WBoard::isFanEnabled() const {
   return digitalRead(FAN_CTRL_PIN) == HIGH;
-}
+}

variants/lilygo_tbeam_1w/TBeam1WBoard.h

@@ -30,6 +30,7 @@
 class TBeam1WBoard : public ESP32Board {
 private:
   bool radio_powered = false;
+  unsigned long _fan_off_millis = 0;  // 0 = no pending fan-off
 
 public:
   void begin();
@@ -39,7 +40,9 @@ class TBeam1WBoard : public ESP32Board {
   const char* getManufacturerName() const override;
   void powerOff() override;
 
-  // Fan control methods
+  // Called each main loop iteration to manage fan cooldown after TX
+  void updateFan();
+
   void setFanEnabled(bool enabled);
   bool isFanEnabled() const;
-};
+};

variants/lilygo_tbeam_1w/platformio.ini

@@ -1,6 +1,7 @@
 [LilyGo_TBeam_1W]
 extends = esp32_base
 board = t_beam_1w
+board_build.partitions = default_16MB.csv
 build_flags =
   ${esp32_base.build_flags}
   -I variants/lilygo_tbeam_1w
@@ -27,13 +28,20 @@ build_flags =
   -D SX126X_DIO3_TCXO_VOLTAGE=3.0
   -D SX126X_CURRENT_LIMIT=140
   -D SX126X_RX_BOOSTED_GAIN=1
+  -D SX126X_REGISTER_PATCH=1       ; Patch register 0x8B5 for improved RX with external PA+LNA FEM
 
   ; TX power: 22dBm to SX1262, PA module adds ~10dB for 32dBm total
   -D LORA_TX_POWER=22
 
+  ; AGC reset interval default: 60 seconds (value * 4000ms).
+  ; Periodically recalibrates the SX1262 frontend to prevent progressive
+  ; deafness caused by the receiver getting stuck in a high-attenuation state
+  ; after repeated TX/RX transitions with the external PA+LNA module.
+  -D DEFAULT_AGC_RESET_INTERVAL=15
+
   ; Battery - 2S 7.4V LiPo (6.0V min, 8.4V max)
   -D BATT_MIN_MILLIVOLTS=6000
-  -D BATT_MAX_MILLIVOLTS=8400
+  -D BATT_MAX_MILLIVOLTS=8200
 
   ; Display - SH1106 OLED at 0x3C
   -D DISPLAY_CLASS=SH1106Display
@@ -154,8 +162,8 @@ build_flags =
   -I examples/companion_radio/ui-new
   -D MAX_CONTACTS=350
   -D MAX_GROUP_CHANNELS=40
-  -D OFFLINE_QUEUE_SIZE=256
   -D WIFI_DEBUG_LOGGING=1
+  -D OFFLINE_QUEUE_SIZE=256
   -D WIFI_SSID='"myssid"'
   -D WIFI_PWD='"mypwd"'
   -D PERSISTANT_GPS=1
@@ -191,4 +199,4 @@ build_src_filter = ${LilyGo_TBeam_1W.build_src_filter}
   +<../examples/simple_repeater>
 lib_deps =
   ${LilyGo_TBeam_1W.lib_deps}
-  ${esp32_ota.lib_deps}
+  ${esp32_ota.lib_deps}

variants/lilygo_tbeam_1w/target.cpp

@@ -63,3 +63,6 @@ mesh::LocalIdentity radio_new_identity() {
   return mesh::LocalIdentity(&rng);
 }
 
+void update_fan_control() {
+  board.updateFan();
+}

variants/lilygo_tbeam_1w/target.h

@@ -25,4 +25,4 @@ uint32_t radio_get_rng_seed();
 void radio_set_params(float freq, float bw, uint8_t sf, uint8_t cr);
 void radio_set_tx_power(int8_t dbm);
 mesh::LocalIdentity radio_new_identity();
-
+void update_fan_control();

variants/lilygo_tbeam_1w/variant.h

@@ -82,6 +82,7 @@
 
 // Fan control
 #define FAN_CTRL_PIN 41
+#define P_FAN_CTRL FAN_CTRL_PIN  // enables update_fan_control() in main loop
 
 // PA Ramp Time - T-Beam 1W requires >800us stabilization (default is 200us)
 // Value 0x05 = RADIOLIB_SX126X_PA_RAMP_800U
@@ -93,4 +94,4 @@
 #define OLED_HEIGHT 64
 
 // 32768 Hz crystal present
-#define HAS_32768HZ 1
+#define HAS_32768HZ 1