Add an external watchdog module

examples/companion_radio/main.cpp

@@ -110,6 +110,10 @@ void setup() {
 
   board.begin();
 
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.begin();
+#endif
+
 #ifdef DISPLAY_CLASS
   DisplayDriver* disp = NULL;
   if (display.begin()) {
@@ -228,4 +232,7 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.loop();
+#endif
 }

examples/simple_repeater/main.cpp

@@ -29,6 +29,10 @@ void setup() {
 
   board.begin();
 
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.begin();
+#endif
+
   // For power saving
   lastActive = millis(); // mark last active time since boot
 
@@ -124,11 +128,17 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
-
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.loop();
+#endif
   if (the_mesh.getNodePrefs()->powersaving_enabled &&                     // To check if power saving is enabled
       the_mesh.millisHasNowPassed(lastActive + nextSleepinSecs * 1000)) { // To check if it is time to sleep
     if (!the_mesh.hasPendingWork()) { // No pending work. Safe to sleep
+#ifdef HAS_EX_WATCHDOG
+      board.sleep(ex_watchdog.getIntervalMs()>1800?1800:ex_watchdog.getIntervalMs());             // To sleep. Wake up after 30 minutes or when receiving a LoRa packet
+#else
       board.sleep(1800);             // To sleep. Wake up after 30 minutes or when receiving a LoRa packet
+#endif
       lastActive = millis();
       nextSleepinSecs = 5;  // Default: To work for 5s and sleep again
     } else {

examples/simple_room_server/main.cpp

@@ -24,6 +24,10 @@ void setup() {
 
   board.begin();
 
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.begin();
+#endif
+
 #ifdef DISPLAY_CLASS
   if (display.begin()) {
     display.startFrame();
@@ -111,4 +115,7 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.loop();
+#endif
 }

examples/simple_secure_chat/main.cpp

@@ -559,6 +559,10 @@ void setup() {
 
   board.begin();
 
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.begin();
+#endif
+
   if (!radio_init()) { halt(); }
 
   fast_rng.begin(radio_get_rng_seed());
@@ -588,4 +592,7 @@ void setup() {
 void loop() {
   the_mesh.loop();
   rtc_clock.tick();
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.loop();
+#endif
 }

examples/simple_sensor/main.cpp

@@ -58,6 +58,10 @@ void setup() {
 
   board.begin();
 
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.begin();
+#endif
+
 #ifdef DISPLAY_CLASS
   if (display.begin()) {
     display.startFrame();
@@ -145,4 +149,7 @@ void loop() {
   ui_task.loop();
 #endif
   rtc_clock.tick();
+#ifdef HAS_EX_WATCHDOG
+  ex_watchdog.loop();
+#endif
 }

src/helpers/ExWatchdogManager.h

@@ -0,0 +1,11 @@
+#pragma once
+
+class ExWatchdogManager {
+public:
+  unsigned long next_feed_watchdog;
+  ExWatchdogManager() { next_feed_watchdog = 0; }
+  virtual bool begin() { return false; }
+  virtual void loop() { }
+  virtual unsigned long getIntervalMs() const { return 0; }
+  virtual void feed() { }
+};

variants/heltec_mesh_solar/platformio.ini

@@ -14,6 +14,11 @@ build_flags =  ${nrf52_base.build_flags}
   -D LORA_TX_POWER=22
   -D SX126X_CURRENT_LIMIT=140
   -D SX126X_RX_BOOSTED_GAIN=1
+  -D HAS_EX_WATCHDOG
+  -D EX_WATCHDOG_DONE_PIN=9
+  -D EX_WATCHDOG_WAKE_PIN=10
+  -D EX_WATCHDOG_TIMEOUT_MS=480000 ;(6*60*1000) ; 6 minute watchdog
+
 build_src_filter = ${nrf52_base.build_src_filter}
   +<helpers/*.cpp>
   +<../variants/heltec_mesh_solar>

variants/heltec_mesh_solar/target.cpp

@@ -13,6 +13,7 @@ VolatileRTCClock fallback_clock;
 AutoDiscoverRTCClock rtc_clock(fallback_clock);
 MicroNMEALocationProvider nmea = MicroNMEALocationProvider(Serial1);
 SolarSensorManager sensors = SolarSensorManager(nmea);
+SolarExWatchdog ex_watchdog;
 
 #ifdef DISPLAY_CLASS
   DISPLAY_CLASS display;
@@ -121,3 +122,30 @@ bool SolarSensorManager::setSettingValue(const char* name, const char* value) {
   }
   return false;  // not supported
 }
+
+bool SolarExWatchdog::begin() {
+  next_feed_watchdog = 0;
+  pinMode(EX_WATCHDOG_WAKE_PIN, INPUT);
+  pinMode(EX_WATCHDOG_DONE_PIN, OUTPUT);
+  delay(1);
+  digitalWrite(EX_WATCHDOG_DONE_PIN, LOW);
+  delay(1);
+  feed();
+  return true;
+}
+void SolarExWatchdog::loop() {
+  if (millis() > next_feed_watchdog) {
+    feed();
+    next_feed_watchdog = millis() + EX_WATCHDOG_TIMEOUT_MS;
+  }
+}
+
+unsigned long SolarExWatchdog::getIntervalMs() const {
+    return next_feed_watchdog - millis();
+}
+
+void SolarExWatchdog::feed() {
+    digitalWrite(EX_WATCHDOG_DONE_PIN, HIGH);
+    delay(1);
+    digitalWrite(EX_WATCHDOG_DONE_PIN, LOW);
+}

variants/heltec_mesh_solar/target.h

@@ -8,6 +8,7 @@
 #include <helpers/AutoDiscoverRTCClock.h>
 #include <helpers/SensorManager.h>
 #include <helpers/sensors/LocationProvider.h>
+#include <helpers/ExWatchdogManager.h>
 #ifdef DISPLAY_CLASS
   #include <helpers/ui/ST7789Display.h>
 #endif
@@ -30,10 +31,20 @@ public:
   bool setSettingValue(const char* name, const char* value) override;
 };
 
+class SolarExWatchdog : public ExWatchdogManager {
+public:
+    SolarExWatchdog() {}
+    bool begin() override;
+    void loop() override;
+    unsigned long getIntervalMs() const override;
+    void feed() override;
+};
+
 extern MeshSolarBoard board;
 extern WRAPPER_CLASS radio_driver;
 extern AutoDiscoverRTCClock rtc_clock;
 extern SolarSensorManager sensors;
+extern SolarExWatchdog ex_watchdog;
 
 #ifdef DISPLAY_CLASS
   extern DISPLAY_CLASS display;

variants/heltec_mesh_solar/variant.h

@@ -34,8 +34,8 @@
 #define PIN_SERIAL1_RX          (37)
 #define PIN_SERIAL1_TX          (39)
 
-#define PIN_SERIAL2_RX          (9)
+#define PIN_SERIAL2_RX          (-1)
-#define PIN_SERIAL2_TX          (10)
+#define PIN_SERIAL2_TX          (-1)
 
 ////////////////////////////////////////////////////////////////////////////////
 // I2C pin definition