Diff: rtc.c

Revision:

17:927fc1eceb9d

Parent:

0:33686e88f09a

Child:

18:207dd1474cd9

--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/rtc.c	Thu Jan 11 17:39:36 2018 +0000
@@ -0,0 +1,40 @@
+#include <time.h>
+#include "peripherals.h"
+
+int  RtcIsSet() { return !(LPC_RTC->RTC_AUX & 0x10); } //27.6.2.5 RTC Auxiliary control register - RTC Oscillator Fail detect flag
+
+void RtcGetTm(struct tm* ptm)
+{
+    ptm->tm_sec    = LPC_RTC->SEC;
+    ptm->tm_min    = LPC_RTC->MIN;
+    ptm->tm_hour   = LPC_RTC->HOUR;
+    ptm->tm_mday   = LPC_RTC->DOM;
+    ptm->tm_mon    = LPC_RTC->MONTH - 1;
+    ptm->tm_year   = LPC_RTC->YEAR  - 1900;
+    ptm->tm_wday   = LPC_RTC->DOW;
+    ptm->tm_yday   = LPC_RTC->DOY   - 1;
+    ptm->tm_isdst  = -1; // -ve should signify that dst data is not available but it is used here to denote UTC
+}
+void RtcSetTm(struct tm* ptm)
+{
+    LPC_RTC->CCR     = 2;                   //Stop and reset the divider (CTCRST bit 1 = 1)
+    LPC_RTC->SEC     = ptm->tm_sec;         // 0 --> 59
+    LPC_RTC->MIN     = ptm->tm_min;         // 0 --> 59
+    LPC_RTC->HOUR    = ptm->tm_hour;        // 0 --> 23
+    LPC_RTC->DOM     = ptm->tm_mday;        // 1 --> 31
+    LPC_RTC->MONTH   = ptm->tm_mon  + 1;    // rtc    1 -->   12; tm 0 -->  11
+    LPC_RTC->YEAR    = ptm->tm_year + 1900; // rtc 1900 --> 2100; tm 0 --> 200
+    LPC_RTC->DOW     = ptm->tm_wday;        // 0 --> 6 where 0 == Sunday
+    LPC_RTC->DOY     = ptm->tm_yday + 1;    // rtc 1 --> 366;     tm 0 --> 365 
+    LPC_RTC->RTC_AUX = 0x10;                //27.6.2.5 RTC Auxiliary control register - RTC Oscillator Fail detect flag - Writing a 1 to this bit clears the flag.
+    LPC_RTC->CCR     = 1;                   //Release the divider (CTCRST bit 1 = 0)
+}
+void RtcInit()
+{
+    LPC_RTC->CCR       =    1;    //27.6.2.2 Clock Control Register - enable the time counters (CLKEN bit 0 = 1); no reset (CTCRST bit 1 = 0); enable calibration counter (CCALEN bit 4 = 0)
+    LPC_RTC->CIIR      =    0;    //27.6.2.3 Counter Increment Interrupt Register - set to not interrupt
+    LPC_RTC->AMR       = 0xFF;    //27.6.2.4 Alarm Mask Register - mask all alarms
+    LPC_RTC->RTC_AUXEN =    0;    //27.6.2.6 RTC Auxiliary Enable register - mask the oscillator stopped interrupt
+    LPC_RTC->ILR       =    3;    //27.6.2.1 Interrupt Location Register - Clear all interrupts
+
+}