Update DST_Europe.ino with enhancd dstclock function

The DSTclock procedure is made visible so that it can be used to convert time from and to DST time. However, if the need exists to convert the actual time to standard time, this procedure did not function correctly. This is improved in this new version.

examples/DST_Europe/DST_Europe.ino

@@ -8,14 +8,16 @@
 RTC_DS3231 rtc; 
 //RTC_DS1307 rtc;
 
-#define USEDST  true // Use DST (true or false)
 #define BAUD   57600 // Baud rate for the serial monitor
-#define getclock() dstclock(rtc.now()) // Improve code readability: replace getclock() with dstclock(rtc.now())
+#define USEDST  true // Use DST (true or false)
+#define StoA       1 // Standard (stored) time to actual time
+#define AtoS       2 // Actual time to standard (stored) time
+#define getclock() dstclock(rtc.now(), 1) // Improve code readability: replace getclock() with dstclock(rtc.now(), StoA)
 
 DateTime now; 
 int lastsec;
 
-DateTime dstclock(DateTime n) { // Return the given (DST adjusted) date and time according to DST settings (for extensive date and time calculations)
+DateTime dstclock(DateTime n, int type) { // Return the given (DST adjusted) date and time according to DST settings (for extensive date and time calculations)
 
   DateTime b, e;
 
@@ -24,14 +26,15 @@ DateTime dstclock(DateTime n) { // Return the given (DST adjusted) date and time
   e = DateTime(n.year(), 10, 31, 2, 0, 0); // End of DST: set on October 31 2:00 (am)
   if (n.month() == 10) e = DateTime(n.year(), 10, 31 - e.dayOfTheWeek(), 2, 0, 0); // End of DST: adjusted to last sunday in October 2:00 (am) when actual month is October
 
-  if (USEDST && (n >= b) && (n < e)) n = n + TimeSpan(0,1,0,0); // adjust to standard time if DST is used and within summertime 
+  if (USEDST) {
+    if ((type == StoA) && (n >= b) && (n < e)) n = n + TimeSpan(0,1,0,0); else // adjust standard (winter) to actual time if DST is used and within summertime 
+      if ((type == AtoS) && (n >= b) && (n < e)) n = n - TimeSpan(0,1,0,0); // adjust actual to standard (winter) time if DST is used and within summertime 
+  }
   return n;
-}; 
+};  
 
 void setclock(DateTime n) { // if the clock is set during summertime then adjust the clock to standard time
-
-  if (USEDST && (n != dstclock(n))) n = n - TimeSpan(0,1,0,0); // if DST is used and within summertime then adjust to the standard time 
-  rtc.adjust(n); // Set the clock to standard time
+  rtc.adjust(dstclock(n, AtoS)); // Set the clock to standard time
 }; 
 
 void setup() {