blink the led very briefly every 5 secs while in light sleep

src/GPS.cpp

@@ -2,6 +2,7 @@
 #include "GPS.h"
 #include "time.h"
 #include <sys/time.h>
+#include "configuration.h"
 
 // stuff that really should be in in the instance instead...
 HardwareSerial _serial_gps(GPS_SERIAL_NUM);
@@ -12,7 +13,7 @@ RTC_DATA_ATTR bool timeSetFromGPS; // We only reset our time once per _boot_ aft
 
 GPS gps;
 bool hasValidLocation; // default to false, until we complete our first read
-bool wantNewLocation = true; 
+bool wantNewLocation = true;
 
 GPS::GPS() : PeriodicTask()
 {
@@ -98,12 +99,15 @@ void GPS::doTask()
     while (_serial_gps.available())
     {
         encode(_serial_gps.read());
+        // DEBUG_MSG("Got GPS response\n");
     }
 
     if (!timeSetFromGPS && time.isValid() && date.isValid())
     {
         struct timeval tv;
 
+        DEBUG_MSG("Got time from GPS\n");
+
         /* Convert to unix time 
         The Unix epoch (or Unix time or POSIX time or Unix timestamp) is the number of seconds that have elapsed since January 1, 1970 (midnight UTC/GMT), not counting leap seconds (in ISO 8601: 1970-01-01T00:00:00Z). 
         */
@@ -137,7 +141,7 @@ void GPS::doTask()
     setPeriod(hasValidLocation && !wantNewLocation ? 30 * 1000 : 100);
 }
 
-void GPS::startLock() 
+void GPS::startLock()
 {
     DEBUG_MSG("Looking for GPS lock\n");
     wantNewLocation = true;

src/PowerFSM.cpp

@@ -43,11 +43,27 @@ static void lsEnter()
 
 static void lsIdle()
 {
-    doLightSleep(radioConfig.preferences.ls_secs * 1000LL);
-    
-    // FIXME - blink led when we occasionally wake from timer, then go back to light sleep
+    uint32_t secsSlept = 0;
+    esp_sleep_source_t wakeCause = ESP_SLEEP_WAKEUP_UNDEFINED;
 
-    // Regardless of why we woke (for now) just transition to NB
+    while (secsSlept < radioConfig.preferences.ls_secs)
+    {
+        // Briefly come out of sleep long enough to blink the led once every few seconds
+        uint32_t sleepTime = 5;
+
+        setLed(false); // Never leave led on while in light sleep
+        wakeCause = doLightSleep(sleepTime * 1000LL);
+        if (wakeCause != ESP_SLEEP_WAKEUP_TIMER)
+            break;
+
+        setLed(true); // briefly turn on led
+        doLightSleep(1);
+        if (wakeCause != ESP_SLEEP_WAKEUP_TIMER)
+            break;
+    }
+    setLed(false);
+
+    // Regardless of why we woke (for now) just transition to NB (and that state will handle stuff like IRQs etc)
     powerFSM.trigger(EVENT_WAKE_TIMER);
 }
 

src/screen.cpp

@@ -651,13 +651,6 @@ void Screen::doTask()
                 nodeDB.updateGUI = false;
                 nodeDB.updateTextMessage = false;
             }
-
-/*
-            if (millis() - lastPressMs > SCREEN_SLEEP_MS)
-            {
-                DEBUG_MSG("screen timeout, turn it off for now...\n");
-                screen.setOn(false);
-            } */
         }
     }
 

src/sleep.cpp

@@ -209,11 +209,11 @@ void setBluetoothEnable(bool on)
  */
 esp_sleep_wakeup_cause_t doLightSleep(uint64_t sleepMsec) // FIXME, use a more reasonable default
 {
-  DEBUG_MSG("Enter light sleep\n");
+  //DEBUG_MSG("Enter light sleep\n");
   uint64_t sleepUsec = sleepMsec * 1000LL;
 
+  Serial.flush(); // send all our characters before we stop cpu clock
   setBluetoothEnable(false); // has to be off before calling light sleep
-  setLed(false);      // Never leave led on while in light sleep
 
   // NOTE! ESP docs say we must disable bluetooth and wifi before light sleep
 
@@ -228,7 +228,7 @@ esp_sleep_wakeup_cause_t doLightSleep(uint64_t sleepMsec) // FIXME, use a more r
   assert(esp_sleep_enable_gpio_wakeup() == ESP_OK);
   assert(esp_sleep_enable_timer_wakeup(sleepUsec) == ESP_OK);
   assert(esp_light_sleep_start() == ESP_OK);
-  DEBUG_MSG("Exit light sleep\n");
+  //DEBUG_MSG("Exit light sleep\n");
   return esp_sleep_get_wakeup_cause();
 }