Diff: TimeUtilities.cpp

Revision:

5:fbbdf57675c3

Parent:

3:524ad47afdc7

Child:

6:a517fee06e2e

--- a/TimeUtilities.cpp	Sat Jul 16 16:57:22 2011 +0000
+++ b/TimeUtilities.cpp	Sun Oct 30 23:42:43 2011 +0000
@@ -15,19 +15,13 @@
 ///
 /// @author David Smart, Smartware Computing
 ///
-/// Version History
-/// 20110616
-/// \li minor documentation changes
-/// 20110601
-/// \li discovered the CCALEN flag to enable calibration
-/// 20110529
-/// \li original version
-///
 #ifndef WIN32
 // embedded build
 #include "mbed.h"
 #endif
 
+#define VERSION "1.03"
+
 #include "TimeUtilities.h"
 #include <time.h>
 #include <string.h>
@@ -38,7 +32,8 @@
 // Fake it out for Win32 development and testing
 struct LPC {
     unsigned long CCR;          // Clock Control register
-    unsigned long GPREG0;       // General Purpose Register - Battery backed
+    unsigned long GPREG0;       // General Purpose Register #0 - 32-bit Battery backed
+    unsigned long GPREG1;       // General Purpose Register #1 - 32-bit Battery backed
     unsigned long CALIBRATION;  // Calibration Register
 };
 struct LPC X;
@@ -48,6 +43,10 @@
 
 static int tzOffsetHr = 0;       ///!< time zone offset hours to print time in local time
 static int tzOffsetMin = 0;      ///!< time zone offset minutes to print time in local time
+static time_t timeWhenLastSet = 0;
+
+
+static const char ver[] = VERSION;
 
 static int SignOf(const int i) {
     return (i >= 0) ? 1 : -1;
@@ -56,12 +55,25 @@
 
 RealTimeClock::RealTimeClock() {
     GetTimeOffsetStore();
+    GetTimeLastSetStore();
 }
 
 
 RealTimeClock::~RealTimeClock() {
 }
 
+const char * RealTimeClock::GetVersion() {
+    return ver;
+}
+
+time_t RealTimeClock::GetTimeValue() {
+    return time(NULL);
+}
+
+time_t RealTimeClock::GetTimeValueWhenSet() {
+    return timeWhenLastSet;
+}
+
 
 void RealTimeClock::GetTimeString(char *buf, time_t tValue) {
     GetTimeOffsetStore();       // Load the time zone offset values from the battery ram
@@ -126,6 +138,13 @@
     tzOffsetMin = (LPC_RTC->GPREG0 & 0xFF);
 }
 
+void RealTimeClock::SetTimeLastSetStore() {
+    LPC_RTC->GPREG1 = timeWhenLastSet;
+}
+
+void RealTimeClock::GetTimeLastSetStore() {
+    timeWhenLastSet = LPC_RTC->GPREG1;
+}
 
 // MM/DD/YYYY HH:MM:SS [(+/-hh:mm)]
 bool RealTimeClock::SetTime(char * timestring) {
@@ -168,6 +187,8 @@
                             seconds = mktime(t);
                             seconds = seconds - (time_t)(tzOffsetHr * 3600 + tzOffsetMin * 60);
                             set_time(seconds);
+                            timeWhenLastSet = seconds;
+                            SetTimeLastSetStore();
                         }
                     }
                 }
@@ -177,3 +198,34 @@
     return success;
 }
 
+bool RealTimeClock::AdjustBySeconds(int32_t adjustSeconds) {
+    if (timeWhenLastSet != 0) {
+        time_t seconds = time(NULL);    // get "now" according to the rtc
+        int32_t delta = seconds - timeWhenLastSet;
+        int32_t curCal = GetTimeCalibration();
+        int32_t calMAX = 131071;
+        int32_t secPerDay = 86400;
+        float errSecPerDay;
+                
+        // Make the clock correct
+        seconds = seconds + adjustSeconds;
+        set_time(seconds);
+        
+        // Convert the current calibration and the adjustment into
+        // the new calibration value
+        // assume it is +10sec and it has been 2days, then the adjustment
+        // needs to be +5 sec per day, or one adjustment every 1/5th 
+        // of a day, or 1 adjustment every 86400/5 counts.
+        // delta = now - then (number of elapsed seconds)
+        if (adjustSeconds != 0 && delta != 0) {
+            int32_t calFactor;
+            errSecPerDay = (float)adjustSeconds / ((float)(delta)/secPerDay);
+            calFactor = (int32_t)((float)secPerDay/errSecPerDay);
+            if (abs(calFactor) < calMAX)
+                SetTimeCalibration(calFactor);
+        }
+        return true;
+    } else {
+        return false;
+    }
+}
\ No newline at end of file