diff --git a/src/main.c b/src/main.c
--- a/src/main.c
+++ b/src/main.c
@@ -33,7 +33,7 @@ enum _state
 };
 
 static void __calc_gridloc(char *dst, double lat, double lon);
-static void ledpulse(void);
+static void __ledpulse(void);
 static void __sleep_enter_stop(void);
 
 uint32_t statled_ontime = 0;
@@ -61,8 +61,8 @@ int main(void)
 //    state = SYSTEM_IDLE;
 
     uint32_t gps_polltimer = 0;
-    uint32_t fix_acq_starttime = 0;
-    uint32_t nextwspr_time = 0;
+    uint64_t fix_acq_starttime = 0;
+    uint64_t nextwspr_time = 0;
     uint8_t nextwspr_time_valid = 0;
     uint64_t last_wspr_tx_time = 0;
     uint64_t idle_blink_last = 0;
@@ -78,18 +78,22 @@ int main(void)
 //    __DBGMCU_CLK_ENABLE() ; // (RCC->APB2ENR |= (RCC_APB2ENR_DBGMCUEN))
 //    HAL_EnableDBGStopMode();  //  SET_BIT(DBGMCU->CR, DBGMCU_CR_DBG_STOP);
 
-
+////////////////////////////////////////////
+///// TODO: MUST synchro RTC to start of 1PPS second to make sure we actually start wspr on time with 1s granularity
+/////////////////////////////////////////
     while (1)
     {
     	// Every 10 minutes, wake up and try to wspr
-    	if(state == SYSTEM_IDLE && (rtc_timestamp() - last_wspr_tx_time > 60000 * 10))
+    	if(state == SYSTEM_IDLE && (rtc_timestamp_seconds() - last_wspr_tx_time >= 60 * 10))
     	{
     		state = SYSTEM_GPSACQ;
     	}
 
         // Update fix status every 2 seconds, only if the GPS is powered on
-        if(HAL_GetTick() - gps_polltimer > 2000)
+        if(rtc_timestamp_seconds() - gps_polltimer >= 3)
         {
+            gps_polltimer = rtc_timestamp_seconds();
+
             if(gps_ison())
             {
             	HAL_GPIO_WritePin(LED_BLUE, 1);
@@ -103,7 +107,7 @@ int main(void)
             	if(gps_getdata()->minute % 2)
             	{
             		// Wait until even minute plus one second, coming soon
-            		nextwspr_time = HAL_GetTick() + (60000 - (gps_getdata()->second * 1000));
+            		nextwspr_time = rtc_timestamp_seconds() + (60 - (gps_getdata()->second * 1));
                     nextwspr_time_valid = 1;
 
             	}
@@ -111,11 +115,10 @@ int main(void)
             	else
             	{
             		// Wait until odd minute, one minute and some change away
-            		nextwspr_time = HAL_GetTick() + 60000 + (60000 - (gps_getdata()->second * 1000));
+            		nextwspr_time = rtc_timestamp_seconds() + 60 + (60 - (gps_getdata()->second * 1));
                     nextwspr_time_valid = 1;
             	}
             }
-            gps_polltimer = HAL_GetTick();
         }
 
 
@@ -153,7 +156,7 @@ int main(void)
 
                 if(!gps_ison())
                 {
-                	fix_acq_starttime = HAL_GetTick();
+                	fix_acq_starttime = rtc_timestamp_seconds();
                     gps_poweron(); // power on and initialize GPS module
                 }
 
@@ -176,13 +179,13 @@ int main(void)
                     adc_start();
                 }
                 // If no decent fix in 3 minutes
-                else if(HAL_GetTick() - fix_acq_starttime > 60000 * 3)
+                else if(rtc_timestamp_seconds() - fix_acq_starttime >= 60 * 3)
                 {
                 	// Flash error code and go to idle, try again next time
                 	led_blink(4);
                     gps_poweroff();
                     fix_acq_starttime = 0;
-                    last_wspr_tx_time = rtc_timestamp(); // repeat acq/tx cycle after big time delay
+                    last_wspr_tx_time = rtc_timestamp_seconds(); // repeat acq/tx cycle after big time delay
                 	state = SYSTEM_IDLE;
                 }
                 else
@@ -203,9 +206,9 @@ int main(void)
 
 
             	// If we're after the minute but not more than 2s after the minute, start tx
-            	if(HAL_GetTick() >= nextwspr_time)
+            	if(rtc_timestamp_seconds() >= nextwspr_time)
             	{
-            		if(HAL_GetTick() < nextwspr_time + 2000)
+            		if(rtc_timestamp_seconds() < nextwspr_time + 2)
             		{
             			volatile double latitude_flt = (double)gps_getdata()->latitude / 10000000.0;
             			volatile double longitude_flt = (double)gps_getdata()->longitude / 10000000.0;
@@ -216,14 +219,14 @@ int main(void)
                         // TODO: Switch between alternate and standard packet
 						wspr_transmit(grid_locator, packet_type);
                         packet_type = !packet_type; // alternate packet type
-						last_wspr_tx_time = rtc_timestamp();
+						last_wspr_tx_time = rtc_timestamp_seconds();
 						state = SYSTEM_IDLE;
                         adc_stop();
             		}
             		else
             		{
             			// Window was missed, go back to idle, and try again after time delay
-						last_wspr_tx_time = rtc_timestamp();
+						last_wspr_tx_time = rtc_timestamp_seconds();
             			state = SYSTEM_IDLE;
                         adc_stop();
             		}
@@ -250,7 +253,7 @@ int main(void)
 		#ifndef LED_DISABLE
 			if((blink_rate != BLINK_DISABLE) && (HAL_GetTick() - led_timer > blink_rate))
 			{
-				ledpulse();
+				__ledpulse();
 				led_timer = HAL_GetTick();
 			}
 
@@ -285,7 +288,7 @@ static void __sleep_enter_stop(void)
 	__HAL_PWR_CLEAR_FLAG(PWR_FLAG_WU);
 }
 
-static void ledpulse(void)
+static void __ledpulse(void)
 {
     HAL_GPIO_WritePin(LED_BLUE, 1);
 	statled_ontime = HAL_GetTick();