Index: RTC.c
===================================================================
diff -u -r757a89d81eede6e9894a4c3199a64cb26bf94923 -r01f42c315442c887cf8050af4ecafa6fe7e7e93b
--- RTC.c	(.../RTC.c)	(revision 757a89d81eede6e9894a4c3199a64cb26bf94923)
+++ RTC.c	(.../RTC.c)	(revision 01f42c315442c887cf8050af4ecafa6fe7e7e93b)
@@ -7,8 +7,8 @@
 *
 * @file    RTC.c
 *
-* @author  (last)      Bill Bracken
-* @date    (last)      30-Jun-2023
+* @author  (last)      Michael Garthwaite
+* @date    (last)      14-Sep-2023
 *
 * @author  (original)  Dara Navaei
 * @date    (original)  11-Jan-2020
@@ -114,6 +114,7 @@
 #define FPGA_ACCURACY_TOLERANCE             12U                         ///< FPGA accuracy tolerance in ms
 #define RTC_PUBLISH_INTERVAL                18U                         ///< RTC publish interval in counts (18)
 #define RTC_REG_ERROR_TIMEOUT_MS            ( 3 * MS_PER_SECOND )       ///< RTC register error timeout in milliseconds.
+#define RTC_BATTERY_LOW_TIMEOUT_MS          ( 3 * MS_PER_SECOND )       ///< RTC battery low timeout in milliseconds.
 
 #define TIMER_COUNTER_TO_REQUEST_READ       18U                         ///< Timer counter for reading time from RTC (18)
 #define MAX_ALLOWED_FAILED_RTC_TRANSFERS    3U                          ///< Max allowed failed RTC transfers (3)
@@ -281,9 +282,11 @@
 
 #ifdef _DG_
     initPersistentAlarm( ALARM_ID_DG_RTC_CONFIG_ERROR, RTC_REG_ERROR_TIMEOUT_MS, RTC_REG_ERROR_TIMEOUT_MS );
+    initPersistentAlarm( ALARM_ID_DG_RTC_BATTERY_LOW, RTC_BATTERY_LOW_TIMEOUT_MS, RTC_BATTERY_LOW_TIMEOUT_MS );
 #endif
 #ifdef _HD_
     initPersistentAlarm( ALARM_ID_HD_RTC_CONFIG_ERROR, RTC_REG_ERROR_TIMEOUT_MS, RTC_REG_ERROR_TIMEOUT_MS );
+    initPersistentAlarm( ALARM_ID_HD_RTC_BATTERY_LOW, RTC_BATTERY_LOW_TIMEOUT_MS, RTC_BATTERY_LOW_TIMEOUT_MS );
 #endif
 }
 
@@ -325,10 +328,6 @@
     {
         isDataOk = FALSE;
     }
-    else if ( ( years - YEAR_2000 ) > MAX_ALLOWED_YEARS )
-    {
-        isDataOk = FALSE;
-    }
     else
     {
         hasWriteToRTCRequested         = TRUE;