RTC_SS
•
S0 is the Reset/Idle state
•
S1 is an OCP wrt cycle of 83E7 0B13h at Kick0 completed state
•
S2 is the UNLOCK MMR WRT state
•
S0 -> S1 when OCP wrt cycle of 83E7 0B13h at Kick0
•
S1 -> S2 when OCP wrt cycle of 95A4 F1E0h at Kick1
•
S1 -> S0 when OCP reset event
•
S2 -> S0 when OCP reset event OR OCP wrt cycle of NOT 83E7 0B13h at Kick0 OR OCP wrt cycle at
Kick1
•
S2 ->S1 when OCP wrt cycle of 83E7 0B13h at Kick0
20.3.3.5.4 Reading the Timer/Calendar (TC) Registers
The TC registers have a read-show register. The reading of the Seconds register will update all of the TC
registers. For example, the Year will only get updated on a reading of the Seconds register. The
time/calendar registers are updated every second as the time changes. During a read of the SECONDS
register, the RTC copies the current values of the time/date registers into shadow read registers. This
isolation assures that the CPU can capture all the time/date values at the moment of the SECONDS read
request and not be subject to changing register values from time updates.
If desired, the RTC also provides a one-time-triggered minute-rounding feature to round the
MINUTE:SECOND registers to the nearest minute (with zero seconds). This feature is enabled by setting
the ROUND_30S bit in the control register (CTRL); the RTC automatically rounds the time values to the
nearest minute upon the next read of the SECONDS register.
NOTE:
Software should always read the Seconds register first. However, the software does not
have to poll any status bit to determine when to read the TC registers.
defines
the TC set that gets shadowed.
Table 20-61. RTC Register Names and Values
Time Unit
Range
Remarks
Year
00 to 99
Month
01 to 12
Day
01 to 31
Months 1, 3, 5, 7, 8, 10, 12
01 to 30
Months 4, 6, 9, 11
01 to 29
Month 2 (leap year)
01 to 28
Month 2 (common year)
Week
00 to 06
Day of week
Hour
00 to 23
24 hour mode
01 to 12
AM/PM mode
Minute
00 to 59
Seconds
00 to 59
20.3.3.5.4.1 Rounding Seconds
Time can be rounded to the closest minute, by setting the ROUND_30S bit of the control register. When
this bit is set, TC values are set to the closest minute value at the next second. The ROUND_30S bit will
be automatically cleared when rounding time is performed.
Example:
•
If current time is 10H59M45S, round operation will change time to 11H00M00S.
•
If current time is 10H59M29S, round operation will change time to 10H59M00S.
3628
Timers
SPRUH73H – October 2011 – Revised April 2013
Copyright © 2011–2013, Texas Instruments Incorporated