Real-time Clock Alarm and Parallel Load Interface Peripheral

RTC (AT91S_RTC) 0xFFFFFE00 (AT91C_BASE_RTC)

Periph ID AIC	Symbol	Description
1	(AT91C_ID_SYS)	System Peripheral

Function	Description
AT91F_RTC_CfgPMC	Enable Peripheral clock in PMC for RTC

RTC Software API (AT91S_RTC)

Offset	Field	Description
0x0	RTC_CR	Control Register
0x4	RTC_MR	Mode Register
0x8	RTC_TIMR	Time Register
0xC	RTC_CALR	Calendar Register
0x10	RTC_TIMALR	Time Alarm Register
0x14	RTC_CALALR	Calendar Alarm Register
0x18	RTC_SR	Status Register
0x1C	RTC_SCCR	Status Clear Command Register
0x20	RTC_IER	Interrupt Enable Register
0x24	RTC_IDR	Interrupt Disable Register
0x28	RTC_IMR	Interrupt Mask Register
0x2C	RTC_VER	Valid Entry Register

Function	Description
AT91F_RTC_InterruptEnable	Enable RTC Interrupt
AT91F_RTC_InterruptDisable	Disable RTC Interrupt
AT91F_RTC_IsInterruptMasked	Test if RTC Interrupt is Masked
AT91F_RTC_GetInterruptMaskStatus	Return RTC Interrupt Mask Status

RTC Register Description

RTC: AT91_REG RTC_CR Control Register

RTC AT91C_RTC_CR 0xFFFFFE00

Offset

Name

Description

RTC_UPDTIM
AT91C_RTC_UPDTIM

Update Request Time Register
0 = No effect.
1 = Stops the RTC time counting.
Time counting consists of second, minute and hour counters. Time counters can be programmed once this bit is set and acknowledged by the bit ACKUPD of the Status Register.

RTC_UPDCAL
AT91C_RTC_UPDCAL

Update Request Calendar Register
0 = No effect.
1 = Stops the RTC calendar counting.
Calendar counting consists of day, date, month, year and century counters. Calendar counters can be programmed once this bit is set.

9..8

RTC_TIMEVSEL
AT91C_RTC_TIMEVSEL

Time Event Selection
The event that generates the flag TIMEV in RTC_SR (Status Register) depends on the value of TIMEVSEL.

Value	Label	Description
0	RTC_TIMEVSEL_MINUTE AT91C_RTC_TIMEVSEL_MINUTE	Minute change.
1	RTC_TIMEVSEL_HOUR AT91C_RTC_TIMEVSEL_HOUR	Hour change.
2	RTC_TIMEVSEL_DAY24 AT91C_RTC_TIMEVSEL_DAY24	Every day at midnight.
3	RTC_TIMEVSEL_DAY12 AT91C_RTC_TIMEVSEL_DAY12	Every day at noon.

17..16

RTC_CALEVSEL
AT91C_RTC_CALEVSEL

Calendar Event Selection
The event that generates the flag CALEV in RTC_SR depends on the value of CALEVSEL.

Value	Label	Description
0	RTC_CALEVSEL_WEEK AT91C_RTC_CALEVSEL_WEEK	Week change (every Monday at time 00:00:00).
1	RTC_CALEVSEL_MONTH AT91C_RTC_CALEVSEL_MONTH	Month change (every 01 of each month at time 00:00:00).
2	RTC_CALEVSEL_YEAR AT91C_RTC_CALEVSEL_YEAR	Year change (every January 1 at time 00:00:00).

RTC: AT91_REG RTC_MR Mode Register

RTC AT91C_RTC_MR 0xFFFFFE04

Offset	Name	Description
0	RTC_HRMOD AT91C_RTC_HRMOD	12-24 hour Mode 0 = 24-hour mode is selected. 1 = 12-hour mode is selected. All non-significant bits read zero.

RTC: AT91_REG RTC_TIMR Time Register

RTC AT91C_RTC_TIMR 0xFFFFFE08

Offset	Name	Description
6..0	RTC_SEC AT91C_RTC_SEC	Current Second The range that can be set is 0-59 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
14..8	RTC_MIN AT91C_RTC_MIN	Current Minute The range that can be set is 0-59 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
20..16	RTC_HOUR AT91C_RTC_HOUR	Current Hour The range that can be set is 1-12 (BCD) in 12-hour mode or 0-23 (BCD) in 24-hour mode.
22	RTC_AMPM AT91C_RTC_AMPM	Ante Meridiem, Post Meridiem Indicator This bit is the AM/PM indicator in 12-hour mode. 0 = AM. 1 = PM. All non-significant bits read zero.

RTC: AT91_REG RTC_CALR Calendar Register

RTC AT91C_RTC_CALR 0xFFFFFE0C

Offset	Name	Description
5..0	RTC_CENT AT91C_RTC_CENT	Current Century The range that can be set is 19-20 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
15..8	RTC_YEAR AT91C_RTC_YEAR	Current Year The range that can be set is 00-99 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
20..16	RTC_MONTH AT91C_RTC_MONTH	Current Month The range that can be set is 01-12 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
23..21	RTC_DAY AT91C_RTC_DAY	Current Day The range that can be set is 1-7 (BCD). The significance of the number (which number represents which day) is user defined as it has no effect on the date counter.
29..24	RTC_DATE AT91C_RTC_DATE	Current Date The range that can be set is 01-31 (BCD). The lowest four bits encode the units. The higher bits encode the tens.

RTC: AT91_REG RTC_TIMALR Time Alarm Register

RTC AT91C_RTC_TIMALR 0xFFFFFE10

Offset	Name	Description
6..0	RTC_SEC AT91C_RTC_SEC	Current Second The range that can be set is 0-59 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
7	RTC_SECEN AT91C_RTC_SECEN	Second Alarm Enable 0 = The second-matching alarm is disabled. 1 = The second-matching alarm is enabled.
14..8	RTC_MIN AT91C_RTC_MIN	Current Minute The range that can be set is 0-59 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
15	RTC_MINEN AT91C_RTC_MINEN	Minute Alarm 0 = The minute-matching alarm is disabled. 1 = The minute-matching alarm is enabled.
20..16	RTC_HOUR AT91C_RTC_HOUR	Current Hour The range that can be set is 1-12 (BCD) in 12-hour mode or 0-23 (BCD) in 24-hour mode.
22	RTC_AMPM AT91C_RTC_AMPM	Ante Meridiem, Post Meridiem Indicator This bit is the AM/PM indicator in 12-hour mode. 0 = AM. 1 = PM. All non-significant bits read zero.
23	RTC_HOUREN AT91C_RTC_HOUREN	Current Hour 0 = The hour-matching alarm is disabled. 1 = The hour-matching alarm is enabled.

RTC: AT91_REG RTC_CALALR Calendar Alarm Register

RTC AT91C_RTC_CALALR 0xFFFFFE14

Offset	Name	Description
20..16	RTC_MONTH AT91C_RTC_MONTH	Current Month The range that can be set is 01-12 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
23	RTC_MONTHEN AT91C_RTC_MONTHEN	Month Alarm Enable 0 = The month-matching alarm is disabled. 1 = The month-matching alarm is enabled.
29..24	RTC_DATE AT91C_RTC_DATE	Current Date The range that can be set is 01-31 (BCD). The lowest four bits encode the units. The higher bits encode the tens.
31	RTC_DATEEN AT91C_RTC_DATEEN	Date Alarm Enable 0 = The date-matching alarm is disabled. 1 = The date-matching alarm is enabled.

RTC: AT91_REG RTC_SR Status Register

RTC AT91C_RTC_SR 0xFFFFFE18

Offset	Name	Description
0	RTC_ACKUPD AT91C_RTC_ACKUPD	Acknowledge for Update 0 = Time and Calendar registers cannot be updated. 1 = Time and Calendar registers can be updated.
1	RTC_ALARM AT91C_RTC_ALARM	Alarm Flag 0 = No alarm matching condition occurred. 1 = An alarm matching condition has occurred.
2	RTC_SECEV AT91C_RTC_SECEV	Second Event 0 = No second event has occurred since the last clear. 1 = At least one second event has occurred since the last clear.
3	RTC_TIMEV AT91C_RTC_TIMEV	Time Event 0 = No time event has occurred since the last clear. 1 = At least one time event has occurred since the last clear. The time event is selected in the TIMEVSEL field in RTC_CTRL (Control Register) and can be any one of the following events: minute change, hour change, noon, midnight (day change).
4	RTC_CALEV AT91C_RTC_CALEV	Calendar event 0 = No calendar event has occurred since the last clear. 1 = At least one calendar event has occurred since the last clear. The calendar event is selected in the CALEVSEL field in RTC_CTRL and can be any one of the following events: week change, month change, year change.s

RTC: AT91_REG RTC_SCCR Status Clear Command Register

RTC AT91C_RTC_SCCR 0xFFFFFE1C

Offset	Name	Description
0	RTC_ACKUPD AT91C_RTC_ACKUPD	Acknowledge for Update 0 = Time and Calendar registers cannot be updated. 1 = Time and Calendar registers can be updated.
1	RTC_ALARM AT91C_RTC_ALARM	Alarm Flag 0 = No alarm matching condition occurred. 1 = An alarm matching condition has occurred.
2	RTC_SECEV AT91C_RTC_SECEV	Second Event 0 = No second event has occurred since the last clear. 1 = At least one second event has occurred since the last clear.
3	RTC_TIMEV AT91C_RTC_TIMEV	Time Event 0 = No time event has occurred since the last clear. 1 = At least one time event has occurred since the last clear. The time event is selected in the TIMEVSEL field in RTC_CTRL (Control Register) and can be any one of the following events: minute change, hour change, noon, midnight (day change).
4	RTC_CALEV AT91C_RTC_CALEV	Calendar event 0 = No calendar event has occurred since the last clear. 1 = At least one calendar event has occurred since the last clear. The calendar event is selected in the CALEVSEL field in RTC_CTRL and can be any one of the following events: week change, month change, year change.s

RTC: AT91_REG RTC_IER Interrupt Enable Register

RTC AT91C_RTC_IER 0xFFFFFE20

Offset	Name	Description
0	RTC_ACKUPD AT91C_RTC_ACKUPD	Acknowledge for Update 0 = Time and Calendar registers cannot be updated. 1 = Time and Calendar registers can be updated.
1	RTC_ALARM AT91C_RTC_ALARM	Alarm Flag 0 = No alarm matching condition occurred. 1 = An alarm matching condition has occurred.
2	RTC_SECEV AT91C_RTC_SECEV	Second Event 0 = No second event has occurred since the last clear. 1 = At least one second event has occurred since the last clear.
3	RTC_TIMEV AT91C_RTC_TIMEV	Time Event 0 = No time event has occurred since the last clear. 1 = At least one time event has occurred since the last clear. The time event is selected in the TIMEVSEL field in RTC_CTRL (Control Register) and can be any one of the following events: minute change, hour change, noon, midnight (day change).
4	RTC_CALEV AT91C_RTC_CALEV	Calendar event 0 = No calendar event has occurred since the last clear. 1 = At least one calendar event has occurred since the last clear. The calendar event is selected in the CALEVSEL field in RTC_CTRL and can be any one of the following events: week change, month change, year change.s

RTC: AT91_REG RTC_IDR Interrupt Disable Register

RTC AT91C_RTC_IDR 0xFFFFFE24

Offset	Name	Description
0	RTC_ACKUPD AT91C_RTC_ACKUPD	Acknowledge for Update 0 = Time and Calendar registers cannot be updated. 1 = Time and Calendar registers can be updated.
1	RTC_ALARM AT91C_RTC_ALARM	Alarm Flag 0 = No alarm matching condition occurred. 1 = An alarm matching condition has occurred.
2	RTC_SECEV AT91C_RTC_SECEV	Second Event 0 = No second event has occurred since the last clear. 1 = At least one second event has occurred since the last clear.
3	RTC_TIMEV AT91C_RTC_TIMEV	Time Event 0 = No time event has occurred since the last clear. 1 = At least one time event has occurred since the last clear. The time event is selected in the TIMEVSEL field in RTC_CTRL (Control Register) and can be any one of the following events: minute change, hour change, noon, midnight (day change).
4	RTC_CALEV AT91C_RTC_CALEV	Calendar event 0 = No calendar event has occurred since the last clear. 1 = At least one calendar event has occurred since the last clear. The calendar event is selected in the CALEVSEL field in RTC_CTRL and can be any one of the following events: week change, month change, year change.s

RTC: AT91_REG RTC_IMR Interrupt Mask Register

RTC AT91C_RTC_IMR 0xFFFFFE28

Offset	Name	Description
0	RTC_ACKUPD AT91C_RTC_ACKUPD	Acknowledge for Update 0 = Time and Calendar registers cannot be updated. 1 = Time and Calendar registers can be updated.
1	RTC_ALARM AT91C_RTC_ALARM	Alarm Flag 0 = No alarm matching condition occurred. 1 = An alarm matching condition has occurred.
2	RTC_SECEV AT91C_RTC_SECEV	Second Event 0 = No second event has occurred since the last clear. 1 = At least one second event has occurred since the last clear.
3	RTC_TIMEV AT91C_RTC_TIMEV	Time Event 0 = No time event has occurred since the last clear. 1 = At least one time event has occurred since the last clear. The time event is selected in the TIMEVSEL field in RTC_CTRL (Control Register) and can be any one of the following events: minute change, hour change, noon, midnight (day change).
4	RTC_CALEV AT91C_RTC_CALEV	Calendar event 0 = No calendar event has occurred since the last clear. 1 = At least one calendar event has occurred since the last clear. The calendar event is selected in the CALEVSEL field in RTC_CTRL and can be any one of the following events: week change, month change, year change.s

RTC: AT91_REG RTC_VER Valid Entry Register

RTC AT91C_RTC_VER 0xFFFFFE2C

Offset	Name	Description
0	RTC_NVTIM AT91C_RTC_NVTIM	Non valid Time 0 = No invalid data has been detected in RTC_TIMR (Time Register). 1 = RTC_TIMR has contained invalid data since it was last programmed.
1	RTC_NVCAL AT91C_RTC_NVCAL	Non valid Calendar 0 = No invalid data has been detected in RTC_CALR (Calendar Register). 1 = RTC_CALR has contained invalid data since it was last programmed.
2	RTC_NVTIMALR AT91C_RTC_NVTIMALR	Non valid time Alarm 0 = No invalid data has been detected in RTC_TIMALR (Time Alarm Register). 1 = RTC_TIMALR has contained invalid data since it was last programmed.
3	RTC_NVCALALR AT91C_RTC_NVCALALR	Nonvalid Calendar Alarm 0 = No invalid data has been detected in RTC_CALALR (Calendar Alarm Register). 1 = RTC_CALALR has contained invalid data since it was last programmed.