Initial Arduino IDE based on Processing.

build/shared/lib/avrlib/rtc.c

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+/*! \file rtc.c \brief Real-time clock function library. */
+//*****************************************************************************
+//
+// File Name	: 'rtc.c'
+// Title		: Real-time clock function library
+// Author		: Pascal Stang - Copyright (C) 2002
+// Created		: 5/10/2002
+// Revised		: 9/30/2002
+// Version		: 0.6
+// Target MCU	: Atmel AVR Series
+// Editor Tabs	: 4
+//
+// NOTE: This code is currently below version 1.0, and therefore is considered
+// to be lacking in some functionality or documentation, or may not be fully
+// tested.  Nonetheless, you can expect most functions to work.
+//
+// This code is distributed under the GNU Public License
+//		which can be found at http://www.gnu.org/licenses/gpl.txt
+//
+//*****************************************************************************
+
+#ifndef WIN32
+	#include <avr/io.h>
+	#include <avr/signal.h>
+	#include <avr/interrupt.h>
+	#include <avr/pgmspace.h>
+#endif
+
+#include "global.h"
+// include timer support
+#ifdef __AVR_ATmega128__
+	#include "timer128.h"
+#else
+	#include "timer.h"
+#endif
+// include rtc header
+#include "rtc.h"
+
+// Program ROM constants
+static char __attribute__ ((progmem)) MonthDayTable[] = {31,28,31,30,31,30,31,31,30,31,30,31};
+
+// Global variables
+// time registers
+RtcTimeType RtcTime;
+
+void rtcInit(void)
+{
+	// set up timer for RTC operation
+	// initialize real-time registers
+	RtcTime.totaltics = 0;
+	RtcTime.tics = 0;
+	RtcTime.seconds = 0;
+	RtcTime.minutes = 0;
+	RtcTime.hours = 0;
+	RtcTime.day = 1;
+	RtcTime.month = 1;
+	RtcTime.year = 2000;
+
+	// select the correct RTC timer based on bit defines
+	#ifdef AS2
+		// use timer2 for most AVRs
+		// initialize timer 2
+		timer2Init();
+		// count with 32.768KHz/8
+		timer2SetPrescaler(TIMER_CLK_DIV8);
+		// switch to asynchronous input (32KHz crystal)
+		sbi(ASSR, AS2);
+		// attach service to real-time clock interrupt
+		// rtcService() will be called at ((32768/8)/256) = 16Hz
+		timerAttach(TIMER2OVERFLOW_INT, rtcService);
+	#else
+	#ifdef AS0
+		// use timer0 for ATmega103, ATmega128
+		// initialize timer 0
+		timer0Init();
+		// count with 32.768KHz/8
+		timer0SetPrescaler(TIMER_CLK_DIV8);
+		// switch to asynchronous input (32KHz crystal)
+		sbi(ASSR, AS0);
+		// attach service to real-time clock interrupt
+		// rtcService() will be called at ((32768/8)/256) = 16Hz
+		timerAttach(TIMER0OVERFLOW_INT, rtcService);
+	#endif
+	#endif
+}
+
+void rtcService(void)
+{
+	// update real-time clock registers
+	RtcTime.totaltics++;
+	RtcTime.tics++;
+	// check for overflows
+	if(RtcTime.tics == 16)							// tics
+	{
+		RtcTime.tics = 0;
+		RtcTime.seconds++;							// increment seconds
+		if(RtcTime.seconds > 59)					// check seconds overflow
+		{
+			RtcTime.seconds -= 60;
+			RtcTime.minutes++;						// increment minutes
+			if(RtcTime.minutes > 59)				// check minutes overflow
+			{
+				RtcTime.minutes -= 60;
+				RtcTime.hours++;					// increment hours
+				if(RtcTime.hours > 23)				// check hours overflow
+				{
+					RtcTime.hours -= 24;
+					RtcTime.day++;					// increment days
+					// check days overflow
+					if(RtcTime.day == pgm_read_byte(&MonthDayTable[RtcTime.month-1]))
+					{
+						RtcTime.day = 1;
+						RtcTime.month++;			// increment months
+						if(RtcTime.month == 13)		// check months overflow
+						{
+							RtcTime.month = 1;
+							RtcTime.year++;			// increment years
+						}
+					}
+				}
+			}
+		}
+	}
+}
+
+RtcTimeType* rtcGetTime(void)
+{
+	// return the real-time clock data
+	return &RtcTime;
+}
+