Andrew Boyson / clock

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Dependents:   oldheating gps motorhome heating

rtc.c@17:927fc1eceb9d, 2018-01-11 (annotated)

Committer:
andrewboyson
Date:
Thu Jan 11 17:39:36 2018 +0000
Revision:
17:927fc1eceb9d
Parent:
rtc.cpp@0:33686e88f09a
Child:
18:207dd1474cd9
Removed dependence on Mbed OS

Who changed what in which revision?

UserRevisionLine numberNew contents of line
andrewboyson 17:927fc1eceb9d 1 #include <time.h>
andrewboyson 17:927fc1eceb9d 2 #include "peripherals.h"
andrewboyson 0:33686e88f09a 3
andrewboyson 17:927fc1eceb9d 4 int RtcIsSet() { return !(LPC_RTC->RTC_AUX & 0x10); } //27.6.2.5 RTC Auxiliary control register - RTC Oscillator Fail detect flag
andrewboyson 0:33686e88f09a 5
andrewboyson 0:33686e88f09a 6 void RtcGetTm(struct tm* ptm)
andrewboyson 0:33686e88f09a 7 {
andrewboyson 0:33686e88f09a 8 ptm->tm_sec = LPC_RTC->SEC;
andrewboyson 0:33686e88f09a 9 ptm->tm_min = LPC_RTC->MIN;
andrewboyson 0:33686e88f09a 10 ptm->tm_hour = LPC_RTC->HOUR;
andrewboyson 0:33686e88f09a 11 ptm->tm_mday = LPC_RTC->DOM;
andrewboyson 0:33686e88f09a 12 ptm->tm_mon = LPC_RTC->MONTH - 1;
andrewboyson 0:33686e88f09a 13 ptm->tm_year = LPC_RTC->YEAR - 1900;
andrewboyson 0:33686e88f09a 14 ptm->tm_wday = LPC_RTC->DOW;
andrewboyson 0:33686e88f09a 15 ptm->tm_yday = LPC_RTC->DOY - 1;
andrewboyson 0:33686e88f09a 16 ptm->tm_isdst = -1; // -ve should signify that dst data is not available but it is used here to denote UTC
andrewboyson 0:33686e88f09a 17 }
andrewboyson 0:33686e88f09a 18 void RtcSetTm(struct tm* ptm)
andrewboyson 0:33686e88f09a 19 {
andrewboyson 0:33686e88f09a 20 LPC_RTC->CCR = 2; //Stop and reset the divider (CTCRST bit 1 = 1)
andrewboyson 0:33686e88f09a 21 LPC_RTC->SEC = ptm->tm_sec; // 0 --> 59
andrewboyson 0:33686e88f09a 22 LPC_RTC->MIN = ptm->tm_min; // 0 --> 59
andrewboyson 0:33686e88f09a 23 LPC_RTC->HOUR = ptm->tm_hour; // 0 --> 23
andrewboyson 0:33686e88f09a 24 LPC_RTC->DOM = ptm->tm_mday; // 1 --> 31
andrewboyson 0:33686e88f09a 25 LPC_RTC->MONTH = ptm->tm_mon + 1; // rtc 1 --> 12; tm 0 --> 11
andrewboyson 0:33686e88f09a 26 LPC_RTC->YEAR = ptm->tm_year + 1900; // rtc 1900 --> 2100; tm 0 --> 200
andrewboyson 0:33686e88f09a 27 LPC_RTC->DOW = ptm->tm_wday; // 0 --> 6 where 0 == Sunday
andrewboyson 0:33686e88f09a 28 LPC_RTC->DOY = ptm->tm_yday + 1; // rtc 1 --> 366; tm 0 --> 365
andrewboyson 0:33686e88f09a 29 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.
andrewboyson 0:33686e88f09a 30 LPC_RTC->CCR = 1; //Release the divider (CTCRST bit 1 = 0)
andrewboyson 0:33686e88f09a 31 }
andrewboyson 0:33686e88f09a 32 void RtcInit()
andrewboyson 0:33686e88f09a 33 {
andrewboyson 0:33686e88f09a 34 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)
andrewboyson 0:33686e88f09a 35 LPC_RTC->CIIR = 0; //27.6.2.3 Counter Increment Interrupt Register - set to not interrupt
andrewboyson 0:33686e88f09a 36 LPC_RTC->AMR = 0xFF; //27.6.2.4 Alarm Mask Register - mask all alarms
andrewboyson 0:33686e88f09a 37 LPC_RTC->RTC_AUXEN = 0; //27.6.2.6 RTC Auxiliary Enable register - mask the oscillator stopped interrupt
andrewboyson 0:33686e88f09a 38 LPC_RTC->ILR = 3; //27.6.2.1 Interrupt Location Register - Clear all interrupts
andrewboyson 0:33686e88f09a 39
andrewboyson 0:33686e88f09a 40 }