com.dalsemi.system
Class Clock

java.lang.Object
  |
  +--com.dalsemi.system.Clock

public class Clock

extends Object

This class provides access to the TINI Real-Time clock. The methods support setting and getting the clock values. The Real-Time clock on TINI is an 8 byte register that stores the year, month, date, day, hour, minute, second, and hundredth-second in BCD format.

Usage

There are two basic ways to access TINI's Real-Time clock. The faster method is to directly use the values year, month, etc.

      ...
      com.dalsemi.system.Clock C = new com.dalsemi.system.Clock();
      C.getRTC();
      System.out.println("The date is : " + C.getDate() + "/" +
                          C.getMonth() + "/" + C.getYear());
      System.out.println("The time is : " + C.getHour() + ":" +
                         C.getMinute() + ":" + C.getSecond() +
                         "." + C.getHundredth() + C.getPm() ? " PM" : " AM"));
      ...
 

The other method is slower, but provides a mean to translate between the TINI Real-Time clock and the Java timekeeping methods which require a long value of milliseconds that have passed since January 1, 1970. This method is slower, since the Clock class must convert from its internal fields into an amount of milliseconds.

      ...
      com.dalsemi.system.Clock C = new com.dalsemi.system.Clock();
      long time = C.getTickCount();
      System.out.println(new java.util.Date(time));
      ...
 

This class also provides means to set the Real-Time Clock settings. The methods for setting Clock values are analogous to the methods for getting, except that after all fields have been set as desired, programs should call setRTC(). The following code sets the TINI Real-Time clock to October 4, 2000 at 1:43 in the afternoon.

      C.setYear(2000);
      C.setMonth(10);
      C.setDate(4);

      C.setHour(13);
      C.setPm(true);
      C.setMinute(43);

      C.setRTC();
      System.out.println(new java.util.Date(C.getTickCount()));
 

Note that the time printed will probably not be 1:43 PM. The time stored is for GMT. On a TINI with Central Standard Time as the default TimeZone, this program prints out:

    TINI /> java clockdemo.tini
    Wed Oct 4 08:43:59 CST 2000
 

which is correct because CST during Daylight Savings Time (CDT) is 5 hours behind GMT. Also note that getRTC() is not called in the above code example. It is called internally by getTickCount(). Any other 'get' accesses should call getRTC() first.

Field Summary

protected int	date Stores the day of the month.
protected int	day Stores the day of the week (1-7).
protected int	hour Stores the hour (1-12 or 0-23).
protected int	hundredth Stores the hundredth-second.
protected boolean	is12Hour This flag signifies if the value stored in hour is for a 1-12 hour clock that uses AM and PM settings or a 0-23 hour clock that does not use AM and PM settings.
protected int	minute Stores the minute.
protected int	month Stores the month (1-12).
protected boolean	pm Stores the AM/PM selection.
protected int	second Stores the second.
protected int	year Stores the year mod 100.

Constructor Summary

Clock()
Creates a new Clock instance for accessing TINI's Real-Time clock.

Method Summary

static int	bcdToInt(int bcdVal) Converts a BCD integer byte to its binary integer value.
static int	calculateDayOfWeek(int month, int date, int fullYear) Calculates the correct day of the week given the month, day of the month, and year.
boolean	get12Hour() Get the 12/24 Hour mode for the Real-Time Clock.
int	getDate() Get the date (day of month) value for the Real-Time Clock.
int	getDay() Get the day of the week value for the Real-Time Clock.
int	getHour() Get the hour value for the Real-Time Clock.
int	getHundredth() Get the hundredth-second value for the Real-Time Clock.
int	getMinute() Get the minute value for the Real-Time Clock.
int	getMonth() Get the month value for the Real-Time Clock.
boolean	getPm() Get the AM/PM value for the Real Time Clock.
void	getRTC() Reads Real time clock values from hardware clock and places them into Clock instance fields.
int	getSecond() Get the second value for the Real-Time Clock.
long	getTickCount() Get the current time in milliseconds since midnight Jan 1, 1970, UTC.
int	getYear() Get the year value for the Real-Time Clock.
static byte	intToBCD(int intVal) Converts a binary integer byte to its BCD value.
void	set12Hour(boolean is12Hour) Sets the 12/24 hour mode of the Real-Time Clock.
void	setDate(int date) Sets the date (day of the month) value of the Real-Time Clock.
void	setDay(int day) Sets the day of the week value of the Real-Time Clock.
void	setHour(int hour) Sets the hour value of the Real-Time Clock.
void	setHundredth(int hundredth) Sets the hundredth-second value of the Real-Time Clock.
void	setMinute(int minute) Sets the minute value of the Real-Time Clock.
void	setMonth(int month) Sets the month value of the Real-Time Clock.
void	setPm(boolean pm) Sets the AM/PM value of the Real Time Clock.
void	setRTC() Reads the stored values year, month, date, etc.
void	setSecond(int second) Sets the second value of the Real-Time Clock.
void	setTickCount(long millis) Set the current time from a value in milliseconds since Jan 1, 1970, UTC.
void	setYear(int year) Sets the year value of the Real-Time Clock.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

year

protected int year

Stores the year mod 100. This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock. used by the setRTC() method to set the Real-Time Clock.

See Also:

setYear(int), getYear()

month

protected int month

Stores the month (1-12). This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setMonth(int), getMonth()

day

protected int day

Stores the day of the week (1-7). This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setDay(int), getDay()

date

protected int date

Stores the day of the month. This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setDate(int), getDate()

hour

protected int hour

Stores the hour (1-12 or 0-23). This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setHour(int), getHour()

minute

protected int minute

Stores the minute. This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setMinute(int), getMinute()

second

protected int second

Stores the second. This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setSecond(int), getSecond()

hundredth

protected int hundredth

Stores the hundredth-second. This field is set by getRTC() and used by the setRTC() method to set the Real-Time Clock.

See Also:

setHundredth(int), getHundredth()

pm

protected boolean pm

Stores the AM/PM selection. The hour is interpreted based on the value of this flag if the is12Hour flag is set.

See Also:

setPm(boolean), getPm()

is12Hour

protected boolean is12Hour

This flag signifies if the value stored in hour is for a 1-12 hour clock that uses AM and PM settings or a 0-23 hour clock that does not use AM and PM settings.

See Also:

set12Hour(boolean), get12Hour()

Constructor Detail

Clock

public Clock()

Creates a new Clock instance for accessing TINI's Real-Time clock. Also performs a call to getRTC() so the fields of this Clock object initially have valid values.

See Also:

getRTC()

Method Detail

setYear

public void setYear(int year)

Sets the year value of the Real-Time Clock. The clock will only store the value of year mod 100. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock.

Parameters:

year - the year to be set

See Also:

getYear(), setRTC()

getYear

public int getYear()

Get the year value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the year as reported by TINI's Real-Time Clock

See Also:

getRTC(), setYear(int)

setMonth

public void setMonth(int month)

Sets the month value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock.

Parameters:

month - the month to be set

See Also:

getMonth(), setRTC()

getMonth

public int getMonth()

Get the month value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the month as reported by TINI's Real-Time Clock

See Also:

getRTC(), setMonth(int)

setDay

public void setDay(int day)

Sets the day of the week value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock. To facilitate setting the correct day of the week, first call calculateDayOfWeek which calculates the day of the week depending on the year, month, and date.

Parameters:

day - the day of the week to be set

See Also:

calculateDayOfWeek(int,int,int), getDay(), setRTC()

getDay

public int getDay()

Get the day of the week value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the day of the week as reported by TINI's Real-Time Clock

See Also:

getRTC(), setDay(int)

setDate

public void setDate(int date)

Sets the date (day of the month) value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock.

Parameters:

date - the day of the month to be set

See Also:

getDate(), setRTC()

getDate

public int getDate()

Get the date (day of month) value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the day of the month as reported by TINI's Real-Time Clock

See Also:

getRTC(), setDate(int)

setHour

public void setHour(int hour)

Sets the hour value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock. The value actually stored in TINI's Real-Time Clock is also determined by the is12Hour flag and the pm flag.

Parameters:

hour - the hour to be set

See Also:

set12Hour(boolean), setPm(boolean), getHour(), setRTC()

getHour

public int getHour()

Get the hour value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock. The methods get12Hour() and getPm() should also be called to find the exact meaning of the hour value.

Returns:

the hour as reported by TINI's Real-Time Clock

See Also:

getPm(), get12Hour(), getRTC(), setHour(int)

setMinute

public void setMinute(int minute)

Sets the minute value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock.

Parameters:

minute - the minute to be set

See Also:

getMinute(), setRTC()

getMinute

public int getMinute()

Get the minute value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the minute as reported by TINI's Real-Time Clock

See Also:

getRTC(), setMinute(int)

setSecond

public void setSecond(int second)

Sets the second value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock.

Parameters:

second - the second to be set

See Also:

getSecond(), setRTC()

getSecond

public int getSecond()

Get the second value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the second as reported by TINI's Real-Time Clock

See Also:

getRTC(), setSecond(int)

setHundredth

public void setHundredth(int hundredth)

Sets the hundredth-second value of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC() should be performed to actually set the Real-Time Clock.

Parameters:

hundredth - the hundredth-second to be set

See Also:

getHundredth(), setRTC()

getHundredth

public int getHundredth()

Get the hundredth-second value for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock.

Returns:

the hundredth-second as reported by TINI's Real-Time Clock

See Also:

getRTC(), setHundredth(int)

setPm

public void setPm(boolean pm)

Sets the AM/PM value of the Real Time Clock. This only sets the instance variable for this object. A call to setRTC should be performed to actually set the real time clock. Note that the value pf pm only matters if is12Hour is true.

Parameters:

pm - true for PM, false for AM

See Also:

getPm(), setRTC(), set12Hour(boolean)

getPm

public boolean getPm()

Get the AM/PM value for the Real Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock. The value of the pm flag is only relevant if the is12Hour flag is set. If the is12Hour flag is not set, the value for hour will range between 0 and 23, and the pm flag is irrelevant.

Returns:

true for PM, false for AM

See Also:

getRTC(), setPm(boolean), get12Hour(), getHour()

set12Hour

public void set12Hour(boolean is12Hour)

Sets the 12/24 hour mode of the Real-Time Clock. This only sets the instance variable for this object. A call to setRTC should be performed to actually set the real time clock. If the argument is true, then the value of the flag pm matters when setRTC() is called.

Parameters:

is12Hour - true for 12 hour clock, false for 24 hour clock

See Also:

setRTC(), get12Hour(), #setPm()

get12Hour

public boolean get12Hour()

Get the 12/24 Hour mode for the Real-Time Clock. To get the latest value, getRTC() should be called before this method to refresh the value from TINI's Real-Time Clock. If the is12Hour flag is not set, the value for hour will range between 0 and 23, and the pm flag is irrelevant. If the is12Hour flag is set, the value for hour will range between 1 and 12, and the pm flag will be relevant.

Returns:

true for 12 hour clock, false for 24 hour clock

See Also:

getRTC(), getPm(), set12Hour(boolean), getHour()

getRTC

public void getRTC()

Reads Real time clock values from hardware clock and places them into Clock instance fields. This method should be called to refresh the Clock instance fields, and before any 'get' methods are called.

See Also:

setRTC()

getTickCount

public long getTickCount()

Get the current time in milliseconds since midnight Jan 1, 1970, UTC. This method calls getRTC(), so it is unnecessary for callers to do so. The value returned is suitable to be used in calls to Java classes such as java.util.Date and java.util.Calendar.

Note: This method assumes the current year is the year 2000 or later. Since the Real-Time Clock only stores the 2 least significant digits of the year, this method assumes that the clock represents a time after midnight, January 1, 2000.

Returns:

number of milliseconds since midnight, Jan 1, 1970 UTC

See Also:

setTickCount(long)

setTickCount

public void setTickCount(long millis)

Set the current time from a value in milliseconds since Jan 1, 1970, UTC. This method calls setRTC() before exiting. This method must parse the millisecond value into fields for the year, month, date, and so on. This is more time consuming than setting the fields individually.

This method is not written to handle negative values for millis. Also note that this method will only store the 2 least significant digits of the year. Subsequent calls to getTickCount() will add these 2 digits to the year 2000 to come up with the current year. If you call setTickCount() with a value for a date in 1999, then getTickCount() will return you a value for a date in 2099.

Parameters:

millis - number of milliseconds since midnight, Jan 1, 1970 UTC

See Also:

getTickCount()

setRTC

public void setRTC()

Reads the stored values year, month, date, etc. and stores them in TINI's Real-Time Clock. This method performs bounds checking on all values, however it does not ensure that invalid dates (February 30) or days of the week (Friday for October 5 2000) have been entered.

See Also:

getRTC()

calculateDayOfWeek

public static int calculateDayOfWeek(int month,
                                     int date,
                                     int fullYear)

Calculates the correct day of the week given the month, day of the month, and year. This method will not work for dates before 1900 or after the year 3000.

Parameters:

month - the month (1-12)

date - the day of the month

fullYear - the year (not mod 100)

Returns:

The day of the week (1-7). 1 is Saturday, 2 is Sunday, etc.

bcdToInt

public static int bcdToInt(int bcdVal)

Converts a BCD integer byte to its binary integer value.

Parameters:

bcdVal - the BCD integer to convert to a decimal integer

Returns:

the converted decimal integer

See Also:

intToBCD(int)

intToBCD

public static byte intToBCD(int intVal)

Converts a binary integer byte to its BCD value.

Parameters:

intVal - decimal value to convert to BCD

Returns:

the converted BCD integer

See Also:

bcdToInt(int)