PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
1.50
Features
•
Multiple Alarm Options
•
Multiple Overflow Options
•
Daylight Saving Time (DST) Option
General Description
The Real-Time Clock (RTC) component provides accurate time and date information for the
system. The time and date are updated every second based on a 1 pulse per second interrupt
from a 32.768 kHz crystal. Clock accuracy is based on the crystal provided and is typically
20ppm.
The RTC keeps track of the second, minute, hour, day of the week, day of the month, day of the
year, month and year. The day of the week is automatically calculated from the day, month and
year. Daylight saving time may be optionally enabled and supports any start and end date, as
well as a programmable saving time. The start and end dates may be absolute like 24 March or
relative like the 2nd Sunday in May.
The Alarm provides match detection for a second, minute, hour, day of week, day of month, day
of year, month and year. A mask selects what combination of time and date information will be
used to generate the alarm. The alarm flexibility supports periodic alarms such as every 23rd
minute after the hour, or a single alarm such as 4:52 AM on the 28th of September 2043.
User code stubs are provided for periodic code execution based on each of the primary time
intervals. Timer intervals are provided at one second, one minute, one hour, one day, one week,
one month, and one year.
When to use a RTC Component
Use the RTC component when the system requires the current time or date. The RTC may also
be used when the current time and date are not required but accurate timing of events with one
second resolution is required.
Input/Output Connections
The RTC component does not have input or output connections.
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Cypress Semiconductor Corporation • 198 Champion Court • San Jose, CA 95134-1709 • 408-943-2600
Document Number: 001-61548 Rev. *A
Revised November 26, 2010
Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Parameters and Setup
Drag an RTC component onto your design and double-click it to open the Configure dialog.
Figure 1 Configure RTC Dialog
The RTC component contains the following options:
Enable Daylight Saving Time
This parameter allows you to choose if the daylight saving time functionality is enabled in the
RTC component. The default value is unchecked (false).
Start of Week
The start of week parameter allows you to choose start day of the week. Options include:
•
“Sunday” (default): Sunday is start of the week
•
“Monday”: Monday is start of the week
•
“Tuesday”: Tuesday is start of the week
•
“Wednesday”: Wednesday is start of the week
•
“Thursday”: Thursday is start of the week
•
“Friday”: Friday is start of the week
•
“Saturday”: Saturday is start of the week
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Document Number: 001-61548 Rev. *A
PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
Clock Selection
A 32.768 kHz clock should be provided from an external crystal oscillator. The accuracy of this
component is defined by the accuracy of the connected external clock source. Refer to the
PSoC Creator Help, Clock Editor section for information about how to connect and configure the
built-in XTAL_32KHZ clock in your design.
Placement
Not applicable
Resources
API Memory
(Bytes)
Digital Blocks
Resolution
Datapat
hs
Macro
cells
RTC fixed HW *
0
0
Status
Control
Registers Registers
0
Counter7
Flash
RAM
Pins (per
External I/O)
0
?
?
?
0
* One Pulse per Second Interrupt from Power Management used
Application Programming Interface
Application Programming Interface (API) routines allow you to configure the component using
software. The following table lists and describes the interface to each function. The subsequent
sections cover each function in more detail.
By default, PSoC Creator assigns the instance name "RTC_1" to the first instance of a
component in a given design. You can rename it to any unique value that follows the syntactic
rules for identifiers. The instance name becomes the prefix of every global function name,
variable, and constant symbol. For readability, the instance name used in the following table is
"RTC.'
It is recommended to disable the component’s interrupts while calling functions that read/modify
global variables.
Refer also to the Registers section of this data sheet for more information, as needed.
Function
Description
void RTC_Init(void)
Initializes/restores default configuration provided with
the customizer.
void RTC_Enable(void)
Enables the interrupts, one pulse per second, and
interrupt generation on OPPS event.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Function
Description
void RTC_Start(void)
Enables the RTC component.
void RTC_Stop(void)
Stops RTC component operation
void RTC_EnableInt(void)
Enables interrupts of RTC component
void RTC_DisableInt(void)
Disables interrupts of the RTC component, time and
date stop running
void RTC_WriteTime(RTC_TIME_DATE *timeDate)
Writes time and date values as current time and date.
RTC_TIME_DATE *timeDate RTC_ReadTime(void)
Reads the current time and date
void RTC_WriteSecond(uint8 second)
Writes Sec software register value
void RTC_WriteMinute(uint8 minute)
Writes Min software register value
void RTC_WriteHour(uint8 hour)
Writes Hour software register value
void RTC_WriteDayOfMonth(uint8 dayOfMonth)
Writes DayOfMonth software register value
void RTC_WriteMonth(uint8 month)
Writes Month software register value
void RTC_WriteYear(uint16 year)
Writes Year software register value
void RTC_WriteAlarmSecond(uint8 second)
Writes Alarm Sec software register value
void RTC_WriteAlarmMinute(uint8 minute)
Writes Alarm Min software register value
void RTC_WriteAlarmHour(uint8 hour)
Writes Alarm Hour software register value
void RTC_WriteAlarmDayOfMonth(uint8 dayOfWeek)
Writes Alarm DayOfMonth software register value
void RTC_WriteAlarmMonth (uint8 month)
Writes Alarm Month software register value
void RTC_WriteAlarmYear(uint16 year)
Writes Alarm Year software register value
void RTC_WriteAlarmDayOfWeek(uint8 dayOfWeek)
Writes Alarm DayOfWeek software register value
void RTC_WriteAlarmDayOfYear(uint16 dayOfYear)
Writes Alarm DayOfYear software register value
uint8 RTC_ReadSecond(void)
Reads Sec software register value
uint8 RTC_ReadMinute(void)
Reads Min software register value
uint8 RTC_ReadHour(void)
Reads Min software register value
uint8 RTC_ReadDayOfMonth(void)
Reads DayOfMonth software register value
uint8 RTC_ReadMonth(void)
Reads Month software register value
uint16 RTC_ReadYear(void)
Reads Year software register value
uint8 RTC_ReadAlarmSecond(void)
Reads Alarm Sec software register value
uint8 RTC_ReadAlarmMinute(void)
Reads Alarm Min software register value
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
Function
Description
uint8 RTC_ReadAlarmHour(void)
Reads Alarm Hour software register value
uint8 RTC_ReadAlarmDayOfMonth(void)
Reads Alarm DayOfMonth software register value
uint8 RTC_ReadAlarmMonth(void)
Reads Alarm Month software register value
uint16 RTC_ReadAlarmYear(void)
Reads Alarm Year software register value
uint8 RTC_ReadAlarmDayOfWeek(void)
Reads Alarm DayOfWeek software register value
uint16 RTC_ReadAlarmDayOfYear(void)
Reads Alarm DayOfYear software register value
void RTC_WriteAlarmMask(uint16/8 mask)
Writes the Alarm Mask software register with 1 bit per
time/date entry.
void RTC_WriteIntervalMask (uint8 mask)
Writes the Interval Mask software register with 1 bit
per time/date entry.
uint8 RTC_ReadStatus(void)
Reads the Status software register which has flags for
DST (DST), Leap Year (LY) and AM/PM (AM_PM),
Alarm active (AA)
void RTC_WriteDSTMode(uint8 mode)
Writes the DST Mode software register
void RTC_WriteDSTStartHour(uint8 hour)
Writes the DST Start Hour software register.
void RTC_WriteDSTStartDayOfMonth(uint8 dayOfMonth)
Writes the DST Start DayOfMonth software register.
void RTC_WriteDSTStartMonth(uint8 month)
Writes the DST Start Month software register.
void RTC_WriteDSTStartDayOfWeek(uint8 dayOfWeek)
Writes the DST Start DayOfWeek software register.
void RTC_WriteDSTStartWeek(uint8 week)
Writes the DST Start Week software register.
void RTC_WriteDSTStopHour(uint8 hour)
Writes the DST Stop Hour software register.
void RTC_WriteDSTStopDayOfMonth(uint8 dayOfMonth)
Writes the DST Stop DayOfMonth software register.
void RTC_WriteDSTStopMonth(uint8 month)
Writes the DST Stop Month software register.
void RTC_WriteDSTStopDayOfWeek(uint8 dayOfWeek)
Writes the DST Stop DayOfWeek software register.
void RTC_WriteDSTStopWeek(uint8 week)
Writes the DST Stop Week software register.
void RTC_WriteDSTOffset(uint8 offset)
Writes the DST Offset register.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Global Variables
Variable
Description
RTC_initVar
Indicates whether the RTC has been initialized. The variable is initialized to 0 and
set to 1 the first time RTC_Start() is called. This allows the component to restart
without reinitialization after the first call to the RTC_Start() routine.
If reinitialization of the component is required, then the RTC_Init() function can be
called before the RTC_Start() or RTC_Enable() function.
RTC_currentTimeDate
The current time and date values are stored in this variable.
RTC_statusDateTime
This variable has following flags: DST, Leap Year, AM/PM and Active Alarm
statuses.
RTC_intervalCfgMask
This variable is used to define what interrupt stub should be executed.
RTC_alarmCfgTimeDate
The alarm time and date values are stored in this variable.
RTC_alarmCurStatus
This variable is used to indicate current active alarm: seconds alarm is active,
minutes alarm is active and so on.
RTC_alarmCfgMask
This variable is used to mask alarm events: mask seconds alarm, mask minutes
alarm and so on.
RTC_dstModeType
This variable stores DST mode type’s value: ‘0’ – fixed and ‘1’ – relative.
RTC_dstTimeDateStart
The values for the time and date of the DST start.
RTC_dstTimeDateStop
The values for the time and date of the DST stop.
RTC_dstStartStatus
The DST start status.
RTC_dstStopStatus
The DST stop status.
RTC_dstOffsetMin
The DST offset value in minutes.
void RTC_Init (void)
Description:
Initializes/restores the default configuration provided with the customizer.
Parameters:
None.
Return Value:
None.
Side Effects:
None.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
void RTC_Enable(void)
Description:
Enables the interrupts, one pulse per second, and interrupt generation on OPPS event.
Parameters:
None.
Return Value:
None.
Side Effects:
Enables the one pulse per second and central time wheel signals to wake up device from the
low power (Sleep and Alternate Active) modes and leaves them enabled.
void RTC_Start(void)
Description:
Enables the RTC component. This function configures the counter, sets up interrupts, does all
required calculation, and starts the counter.
Parameters:
None.
Return Value:
None.
Side Effects:
Enables the one-pulse per-second and central time wheel signals to wake up the device from
low power modes (Sleep and Alternate Active) and leaves them enabled.
void RTC_Stop(void)
Description:
Stops RTC component operation.
Parameters:
None.
Return Value:
None.
Side Effects:
Leaves the one-pulse per-second and the central time wheel signals enabled, which wake up
the device from low power modes (Sleep and Alternate Active).
void RTC_EnableInt(void)
Description:
Enables interrupts from RTC component.
Parameters:
None.
Return Value:
None.
Side Effects:
None.
void RTC_DisableInt(void)
Description:
Disables interrupts from RTC component, time and date stop running.
Parameters:
None.
Return Value:
None.
Side Effects:
None.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
RTC_TIME_DATE* timeDate RTC_ReadTime(void)
Description:
Reads current time and date.
Parameters:
None.
Return Value:
Pointer to the RTC_TIME_DATE..
Side Effects:
None.
void RTC_WriteTime(RTC_TIME_DATE * timeDate)
Description:
Writes time and date values as current time and date. Only passes the Second, Minute,
Hour, Month, Day of Month and Year.
Parameters:
timeDate: pointer to the RTC_TIME_DATE global structure where new values of time and
date are stored.
Return Value:
None.
Side Effects:
The RTC component’s interrupt should be disabled before calling this function and enabled
afterwards to avoid RTC counter increment in the middle of the time and date writing.
void RTC_WriteSecond(uint8 second)
Description:
Writes the Sec software register value.
Parameters:
second: Seconds value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteMinute(uint8 minute)
Description:
Writes the Min software register value.
Parameters:
minute: Minutes value
Return Value:
None.
Side Effects:
None.
void RTC_WriteHour(uint8 hour)
Description:
Writes the Hour software register value.
Parameters:
hour: Hours value.
Return Value:
None.
Side Effects:
None.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
void RTC_WriteDayOfMonth(uint8 dayOfMonth)
Description:
Writes the DayOfMonth software register value.
Parameters:
dayOfMonth: DayOfMonth value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteMonth(uint8 month)
Description:
Writes the Month software register value.
Parameters:
month: Month value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteYear(uint16 year)
Description:
Writes the Year software register value.
Parameters:
year: Years value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteAlarmSecond(uint8 second)
Description:
Writes the Alarm Sec software register value.
Parameters:
second: Alarm Seconds value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteAlarmMinute(uint8 minute)
Description:
Writes the Alarm Min software register value.
Parameters:
minute: Alarm Minutes value.
Return Value:
None.
Side Effects:
None.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
void RTC_WriteAlarmHour(uint8 hour)
Description:
Writes the Alarm Hour software register value.
Parameters:
hour: Alarm Hours value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteAlarmDayOfMonth(uint8 dayOfMonth)
Description:
Writes the Alarm DayOfMonth software register value.
Parameters:
dayOfMonth: Alarm Day Of Month value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteAlarmMonth(uint8 month)
Description:
Writes the Alarm Month software register value.
Parameters:
month: Alarm Months value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteAlarmYear(uint16 year)
Description:
Writes the Alarm Year software register value.
Parameters:
year: Alarm Years value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteAlarmDayOfWeek(uint8 dayOfWeek)
Description:
Writes the Alarm DayOfWeek software register value.
Parameters:
dayOfWeek: Alarm Day Of Week value.
Return Value:
None.
Side Effects:
None.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
void RTC_WriteAlarmDayOfYear(uint16 dayOfYear)
Description:
Writes the Alarm DayOfYear software register value.
Parameters:
dayOfYear: Alarm Day Of Year value.
Return Value:
None.
Side Effects:
None.
uint8 RTC_ReadSecond(void)
Description:
Reads the Sec software register value.
Parameters:
None.
Return Value:
None.
Side Effects:
None.
uint8 RTC_ReadMinute(void)
Description:
Reads the Min software register value.
Parameters:
None.
Return Value:
The current minute’s value is returned.
Side Effects:
None.
uint8 RTC_ReadHour(void)
Description:
Reads the Min software register value.
Parameters:
None.
Return Value:
The current hour’s value is returned.
Side Effects:
None.
uint8 RTC_ReadDayOfMonth(void)
Description:
Reads the DayOfMonth software register value.
Parameters:
None.
Return Value:
The current day of month’s value is returned.
Side Effects:
None.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
uint8 RTC_ReadMonth(void)
Description:
This function reads the Month software register value.
Parameters:
None.
Return Value:
The current month’s value is returned.
Side Effects:
None.
uint16 RTC_ReadYear(void)
Description:
Reads the Year software register value.
Parameters:
None.
Return Value:
The current year’s value is returned.
Side Effects:
None.
uint8 RTC_ReadAlarmSecond(void)
Description:
Reads the Alarm Sec software register value.
Parameters:
None.
Return Value:
The current second’s alarm value is returned.
Side Effects:
None.
uint8 RTC_ReadAlarmMinute(void)
Description:
Reads the Alarm Min software register value.
Parameters:
None.
Return Value:
The current minute’s alarm value is returned.
Side Effects:
None.
uint8 RTC_ReadAlarmHour(void)
Description:
Reads the Alarm Hour software register value.
Parameters:
None.
Return Value:
The current hour’s alarm value is returned.
Side Effects:
None.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
uint8 RTC_ReadAlarmDayOfMonth(void)
Description:
Reads the Alarm DayOfMonth software register value.
Parameters:
None.
Return Value:
The current day of month’s alarm value is returned.
Side Effects:
None.
uint8 RTC_ReadAlarmMonth(void)
Description:
Reads the Alarm Month software register value.
Parameters:
None.
Return Value:
The current month’s alarm value is returned.
Side Effects:
None.
uint16 RTC_ReadAlarmYear(void)
Description:
Reads the Alarm Year software register value.
Parameters:
None.
Return Value:
The current year’s alarm value is returned..
Side Effects:
None.
uint8 RTC_ReadAlarmDayOfWeek(void)
Description:
Reads the Alarm DayOfWeek software register value.
Parameters:
None.
Return Value:
The current day of week’s alarm value is returned.
Side Effects:
None.
uint16 RTC_ReadAlarmDayOfYear(void)
Description:
Reads the Alarm DayOfYear software register value.
Parameters:
None.
Return Value:
The current day of year’s alarm value is returned.
Side Effects:
None.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
void RTC_WriteAlarmMask(uint8 mask)
Description:
Writes the Alarm Mask software register with 1 bit per time/date entry. Alarm true when all
masked time/date values match Alarm values.
Parameters:
mask: Alarm Mask software register value. Refer to the Alarm Mask Register section for
more information about this parameter.
Return Value:
None.
Side Effects:
None.
void RTC_WriteIntervalMask(uint8 mask)
Description:
Writes the Interval Mask software register with 1 bit per time/date entry. ‘Interrupt’ true when
any masked time/date overflow occur.
Parameters:
mask: Interval Mask software register value. Refer to the Interval Mask Register section for
more information about this parameter.
Return Value:
None.
Side Effects:
None.
uint8 RTC_ReadStatus(void)
Description:
Reads the Status software register which has flags for DST (DST), Leap Year (LY) and
AM/PM (AM_PM), Alarm active (AA).
Parameters:
None.
Return Value:
Current component's status with active alarm bit cleared. Refer to the Status Register
section for more information about the return values.
Side Effects:
Alarm active (AA) flag clear after read.
void RTC_WriteDSTMode(uint8 mode)
Description:
Writes the DST Mode software register That enables or disables DST changes and sets the
date mode to fixed date or relative date. Only generated if DST enabled.
Parameters:
mode: DST Mode software register value.
Return Value:
None.
Side Effects:
None.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
void RTC_WriteDSTStartHour(uint8 hour)
Description:
Writes the DST Start Hour software register. Used for absolute date entry. Only generated if
DST enabled.
Parameters:
hour: DST Start Hour software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStartDayOfMonth(uint8 dayOfMonth)
Description:
Writes the DST Start DayOfMonth software register. Used for absolute date entry. Only
generated if DST enabled.
Parameters:
dayOfMonth: DST Start DayOfMonth software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStartMonth(uint8 month)
Description:
Writes the DST Start Month software register. Used for absolute date entry. Only generated if
DST enabled.
Parameters:
month: DST Start Month software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStartDayOfWeek(uint8 dayOfWeek)
Description:
Writes the DST Start DayOfWeek software register. Used for relative date entry. Only
generated if DST enabled.
Parameters:
dayOfWeek: DST Start DayOfWeek software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStartWeek(uint8 week)
Description:
Writes the DST Start Week software register. Used for relative date entry. Only generated if
DST enabled.
Parameters:
Week: DST Start Week software register value.
Return Value:
None.
Side Effects:
None.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
void RTC_WriteDSTStopHour(uint8 hour)
Description:
Writes the DST Stop Hour software register. Used for absolute date entry. Only generated if
DST enabled.
Parameters:
hour: DST Stop Hour software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStopDayOfMonth(uint8 dayOfMonth)
Description:
Writes the DST Stop DayOfMonth software register. Used for absolute date entry. Only
generated if DST enabled.
Parameters:
dayOfMonth: DST Stop DayOfMonth software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStopMonth(uint8 month)
Description:
Writes the DST Stop Month software register. Used for absolute date entry. Only generated if
DST enabled.
Parameters:
month: DST Stop Month software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStopDayOfWeek(uint8 dayOfWeek)
Description:
Writes the DST Stop DayOfWeek software register. Used for relative date entry. Only
generated if DST enabled.
Parameters:
dayOfWeek: DST Stop DayOfWeek software register value.
Return Value:
None.
Side Effects:
None.
void RTC_WriteDSTStopWeek(uint8 week)
Description:
Writes the DST Stop Week software register. Used for relative date entry. Only generated if
DST enabled.
Parameters:
week: DST Stop Week software register value.
Return Value:
None.
Side Effects:
None.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
void RTC_WriteDSTOffset(uint8 offset)
Description:
Writes the DST Offset register. Allows a configurable increment or decrement of time between
0 and 255 minutes. Increment occurs on DST start and decrement on DST stop. Only
generated if DST enabled.
Parameters:
offset: DST Offset software register value.
Return Value:
None.
Side Effects:
None.
Data Structures
RTC_TIME_DATE
This is the data structure that is used to save the current time and date (RTC_currentTimeDate),
and Alarm time and date (RTC_alarmCfgTimeDate).
typedef struct _RTC_TIME_DATE
{
uint8 Sec;
uint8 Min;
uint8 Hour;
uint8 DayOfWeek;
uint8 DayOfMonth;
uint16 DayOfYear;
uint8 Month;
uint16 Year;
} RTC_TIME_DATE;
RTC_DSTIME
This is the data structure that is used to save time and date values for Daylight Saving Time
Start and Stop (RTC_dstTimeDateStart and RTC_dstTimeDateStop).
typedef struct _RTC_DSTIME
{
uint8 Hour;
uint8 DayOfWeek;
uint8 Week;
uint8 DayOfMonth;
uint8 Month;
} RTC_DSTIME;
Constants
There are several constants that define day of week, day in month, and month. When writing
code use the constants defined in the header (.h) file.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Sample Firmware Source Code PSoC Creator provides numerous example projects that include
schematics and example code in the Find Example Project dialog. For component-specific
examples, open the dialog from the Component Catalog or an instance of the component in a
schematic. For general examples, open the dialog from the Start Page or File menu. As needed,
use the Filter Options in the dialog to narrow the list of projects available to select.
Refer to the "Find Example Project" topic in the PSoC Creator Help for more information.
Interrupt Service Routines
The RTC component uses a single interrupt that triggers every second. The interrupt handler
updates the internal date and time structure, and then calls specific functions at appropriate
intervals. The following functions are called:
•
Every Second handler – RTC_EverySecondHandler()
•
Every Minute handler – RTC_EveryMinuteHandler()
•
Every Hour handler – RTC_EveryHourHandler()
•
Every Day handler – RTC_EveryDayHandler()
•
Every Week handler – RTC_EveryWeekHandler()
•
Every Month handler – RTC_EveryMonthHandler()
•
Every Year handler – RTC_EveryYearHandler()
Stub routines for these functions are provided where you can add your own code. The routine
stubs are generated in the RTC_INT.c file the first time the project is built. Your code must be
added between the provided comment tags as follows:
void RTC_EverySecondHandler( void )
{
/* Place your every second handler code here. */
/* `#START EVERY_SECOND_HANDLER_CODE` */
/* `#END` */
}
All interrupt status bits of the Power Manager Interrupt Status register are cleared in the interrupt
handler. If an interrupt gets generated at the same time as a clear, the bit will remain set (which
causes another interrupt).
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
Functional Description
Time and date
All time and date registers are as accessible as software variables. The time and date change is
based on an interrupt event from the Counter component. The following variables are provided:
•
Sec – seconds 0 – 59
•
Min – minutes 0 – 59
•
Hour – hours (24 format only) 0 – 23
•
DayOfMonth – day of month 1 – 31
•
DayOfWeek – day of week 1 – 7. The number depends on StartOfWeek parameter
settings. If StartOfWeek is set to Sunday then: 1 – Sunday, 2 – Monday…,7 – Saturday
•
DayOfYear – day of year 1 – 366
•
Month – month 1 – 12
•
Year – year, 1900 – 2200 (the actual range is 1 – 65 536)
The DayOfWeek is calculated using Zeller’s congruence. Zeller’s congruence is a simple
algorithm optimized for integer math that calculates the day of the week based on year, month
and day of the month. It accounts for Leap years and leap centuries.
When you call the RTC_Start function, a StartCalculation function is called and all required flags
and date calculations are executed. This includes all variables that need calculation:
•
DayOfWeek
•
DayOfYear
•
LY
•
AM_PM
•
DST
Alarm function
The alarm function provides for seconds, minutes, hours, days of the month, days of the week,
month, year, and day of the year. The same variable names are provided for alarm settings. The
user may set any of all of these alarm settings and configure which of these settings are used in
tripping the alarm.
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Periodic interrupts
Interrupt stubs (locations for user code in separate functions) are provided that can run every
second, minute, hour, day, week, month and year. If code is present in the stub it will be run at
the appropriate interval.
Daylight Saving Time
To enable the Daylight Saving Time feature, select the check box on the Configure dialog (see
Parameters section of this data sheet). Daylight Saving Time is implemented as set of API
update times, dates, and durations. If the current time and date match the start of DST time and
date then the DST flag is set and the time is incremented by the set duration.
The start and stop date of DST can be given as fixed or relative. The relative date converts to the
fixed one and is checked against the current time as if it were an alarm function. An example of a
fixed date is "24 March." An example of a relative date is "4th Sunday in May."
The conversion of a relative date to a fixed date is implemented as a separate function. It is
called at the end of the first hour after the RTC_Start() function is called, and it sets a conversion
flag in the RTC_Start() function itself that indicates the conversion is done. The next conversion
will be in next year.
The DST variables for start and stop time and date are as follows:
•
Hour – hour 0 - 23 (fixed and relative)
•
DayOfWeek – day of week 1 – 7. The number depends on StartOfWeek parameter
settings. If StartOfWeek is set to Sunday then: 1 – Sunday, 2 – Monday, … ,7 – Saturday
(relative)
•
Week – week in month 1 – 5 (relative)
•
DayOfMonth – day of month 1 – 31 (fixed)
•
Month – month 1 – 12 (fixed and relative)
Registers
Status Register
The status register is a read-only register that contains various RTC status bits. This value can
be read using the RTC_ReadStatus() function. There are several bit-field masks defined for the
status register. The #defines are available in the generated header file (.h) as follows:
•
RTC_STATUS_DST – Status of Daylight Saving Time. This bit goes high when the
current time and date match DST time and date and the time is incremented. This bit goes
low after the DST interval and the time is decremented.
•
RTC_STATUS_LY – Status of leap year. This bit goes high when the current year is a
leap year.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
•
RTC_STATUS_AM_PM – Status of current time. This bit is low from midnight to noon and
high from noon to midnight.
•
RTC_STATUS_AA – Status of alarm active (i.e., alarm bit). This bit is high when current
time and date match alarm time and date. Once the status is read this bit goes low.
Alarm Mask Register
The alarm mask register is a write-only register that allows you to control the alarm bit in the
status register. The alarm bit is generated by ORing the masked bit-fields within this register.
This register is written with the RTC_WriteAlarmMask() function call. When writing the alarm
mask register you must use the bit-field definitions as defined in the header (.h) file. The
definitions for the alarm mask register are as follows:
•
RTC_ALARM_SEC_MASK – The second alarm mask allows you to match the alarm
second register with the current second register. The alarm second register is written with
the RTC_WriteAlarmSecond() function call and read with RTC_ReadAlarmSecond().
•
RTC_ALARM_MIN_MASK – The minute alarm mask allows you to match the alarm
minute register with the current minute register. The alarm minute register is written with
the RTC_WriteAlarmMinute() function call and read with the RTC_ReadAlarmMinute().
•
RTC_ALARM_HOUR_MASK – The hour alarm mask allows you to match the alarm hour
register with the current hour register. The alarm hour register is written with the
RTC_WriteAlarmHour() function call and read with the RTC_ReadAlarmHour().
•
RTC_ALARM_DAYOFWEEK_MASK – The day of week alarm mask allows you to match
the alarm day of week register with the current day of week register. The alarm day of
week register is written with the RTC_WriteAlarmDayOfWeek() function call and read with
the RTC_ReadAlarmDayOfWeek().
•
RTC_ALARM_DAYOFMONTH_MASK – The day of month alarm mask allows you to
match the alarm day of month register with the current day of month register. The alarm
day of month register is written with the RTC_WriteAlarmDayOfMonth() function call and
read with the RTC_ReadAlarmDayOfMonth().
•
RTC_ALARM_DAYOFYEAR_MASK – The day of year alarm mask allows you to match
the alarm day of year register with the current day of year register. The alarm day of year
register is written with the RTC_WriteAlarmDayOfYear() function call and read with the
RTC_ReadAlarmDayOfYear().
•
RTC_ALARM_MONTH_MASK – The month alarm mask allows you to match the alarm
month register with the current month register. The alarm month register is written with the
RTC_WriteAlarmMonth() function call and read with the RTC_ReadAlarmMonth().
•
RTC_ALARM_YEAR_MASK – The year alarm mask allows you to match the alarm year
register with the current year register. The alarm year register is written with the
RTC_WriteAlarmYear() function call and read with the RTC_ReadAlarmYear().
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Interval Mask Register
The interval mask register is a write-only register that allows you to control handling of interrupt
stubs of the RTC component. The interrupt stubs are provided for every second, minute, hour,
day, week, month and year. To enable interrupt stub execution, set the appropriate bit in this
register. This register is written with the RTC_WriteIntervalMask() function call. When writing the
interval mask register you must use the bit-field definitions as defined in the header (.h) file. The
definitions for the interval mask register are as follows:
•
RTC_INTERVAL_SEC_MASK – The second interval mask allows handling an interrupt
stub every second.
•
RTC_INTERVAL_MIN_MASK – The minute interval mask allows handling an interrupt
stub every minute.
•
RTC_INTERVAL_HOUR_MASK – The hour interval mask allows handling an interrupt
stub every hour.
•
RTC_INTERVAL_DAY_MASK – The day interval mask allows handling an interrupt stub
every day.
•
RTC_INTERVAL_WEEK_MASK – The week interval mask allows handling an interrupt
stub every week.
•
RTC_INTERVAL_MONTH_MASK – The month interval mask allows handling an interrupt
stub every month.
•
RTC_INTERVAL_YEAR_MASK – The year interval mask allows handling an interrupt
stub every year.
DST Mode Register
The DST mode register is a write only register which allows you to set the Daylight Saving Time
mode and enable DST operation. This register is written with the RTC_WriteDSTMode() function
call. When writing the DST mode register you must use the bit-field definition as defined in the
header (.h) file. The definitions for the DST mode register are as follows:
•
RTC_DST_ENABLE – The enable bit controls enabling the daylight saving time
functionality.
•
RTC_DST_FIXDATE – Defines the fixed format of the times and dates (start and stop) for
daylight saving time functionality. For example, fixed date is 24 March.
•
RTC_DST_RELDATE – Defines the relative format of the times and dates (start and stop)
for daylight saving time functionality. For example, relative date is 2nd Sunday in May.
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PSoC® Creator™ Component Data Sheet
Real-Time Clock (RTC)
Conditional Compilation Information
The RTC API requires one conditional compile definition to handle daylight saving time
functionality. The DST functions are conditionally compiled only if this option is enabled in the
Configure dialog. The software should never use this parameter directly. Instead, use the
symbolic name defined.
•
RTC_DST_FUNC_ENABLE – The daylight saving time functionality enable define is
assigned to be equal to the DstEnable value (from the Configure dialog) at build time. It is
used throughout the API to compile data saving time functions.
References
Not applicable
DC and AC Electrical Characteristics
The following values are indicative of expected performance and based on initial characterization
data.
5.0V/3.3V DC and AC Electrical Characteristics
Parameter
Typical
Min
Max
Units
Conditions and Notes
Input
Input Voltage Range
---
Vss to Vdd
V
Input Capacitance
---
---
pF
Input Impedance
---
---
Maximum Clock Rate
---
32
kHz
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Real-Time Clock (RTC)
PSoC® Creator™ Component Data Sheet
Component Changes
This section lists the major changes in the component from the previous version.
Version
1.50.a
1.50
Description of Changes
Reason for Changes / Impact
The RTC version 1.50 requires cy_boot version
2.x to be used.
The cy_boot component should be updated up to
version 2.x for RTC version 1.50 could be used.
The “Sample Firmware Source Code” section was
updated to note that data sheet example project
has been added.
The data sheet example project was added to the
PSoC Creator.
RTC_Enable() function description was added.
Every function that is exposed to user should be
described in the datasheet.
Added reference for the parameter descriptions of
the following functions: RTC_WriteAlarmMask(),
RTC_WriteIntervalMask(), and
RTC_ReadStatus().
Clarification comments on the functions’ usage.
The Keil reentrancy support was added in version
1.50.
PSoC 3 with the Keil compiler supports the
capability for functions to be called from multiple
flows of control.
The API flow has been changed - the RTC_Init()
function was added.
To comply with corporate standard and provide an
API to initialize/restore the component without
starting it.
Some global variables were renamed to comply
with coding standard. Function headers were
updated to describe function global parameters
usage and returns.
Comply with coding rules. No impacts - macros
were created for backward compatibility.
The data sheet was updated.
Added "Component Changes" section. Added
empty "Side Effects" section to the "Application
Programming Interface" section.
The RTCIsLeapYear(uint16 year) function was
replaced by RTC_LEAP_YEAR macros. The
RTC_SET_ALARM and RTC_IS_BIT_SET were
created. The RTC_IS_BIT_SET macro used in a
few more conditional expressions.
Fixed a bad practice to call functions within ISR,
they were moved out or replaced by macros. Oneline functions should be replaced by macros. The
code, which is used in a few places, should be
replaced by macros.
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Cypress does not assume any liability arising out of the application or use of any product or circuit described herein. Cypress does not authorize its products for use as critical components in lifesupport systems where a malfunction or failure may reasonably be expected to result in significant injury to the user. The inclusion of Cypress’ product in a life-support systems application
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