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Field
Name
R/W
Description
15:0
SUBSEC
R
Sub Second Value Setup
SUBSEC is the value of synchronous prescaler counter. It is determined
by the following formula:
Subsecond value=(SPSC-SUBSEC)/(SPSC+1)
After one shift operation is performed, SUBSEC may be greater than
SPSC. The correct time/date is one second less than
RTC_TIME/RTC_DATE.
31:16
Reserved
RTC shift register (RTC_SHIFT)
This register is in write protection state.
Offset address: 0x2C
Power-on reset value: 0x0000 0000
System reset: 0xXXXX XXXX
Field
Name
R/W
Description
14:0
SFSEC
W
Subtract a Fraction of a Second Setup
This bit field can only be written; read this byte and it is always 0. Writing
to this bit is invalid while an operation is being executed.
The set SFSEC value will be added to the synchronous prescaler counter.
If the counter counts down, the clock will be delayed, and the delay time is
determined by the following formula:
Delay (seconds)=SFSEC/(SPSC+1)
When it takes effect at the same time with ADD1SECEN, the advance
clock will be added by a fraction of a second; the specific added value is
determined by the following formula:
Advance(seconds)=(1-(SFSEC/(SPSC+1)))
Conduct write operation to this bit and RSFLG bit can be cleared. The
software keeps running until RSFLG is set to 1 to ensure that the value of
the shadow register is synchronized with the shift time.
30:15
Reserved
31
ADD1SECEN
W
Add One Second Enable
0: Not added
1: The clock/calender increases by one second
This bit can only be written; read this byte and it is always 0. Writing to this
bit is invalid while an operation is being executed.
When it takes effect at the same time with SFSEC, it can increase the
value of the clock by several tenths of a second.
RTC timestamp time register (RTC_TSTIME)
This register is valid only when TSFLG of RTC_STS is set to 1. When TSFLG bit
is reset, the content of this register will be cleared.
Offset address: 0x30
Power-on reset value: 0x0000 0000
System reset: 0xXXXX XXXX
Field
Name
R/W
Description
3:0
SECU
R
Second Ones Unit in BCD Format Setup
