NXP Semiconductors K22F series, Reference Manual, Page: 1054 / 1407

RTC_TSR field descriptions (continued)
Field Description
When the time counter is enabled, the TSR is read only and increments once a second provided SR[TOF]
or SR[TIF] are not set. The time counter will read as zero when SR[TOF] or SR[TIF] are set. When the
time counter is disabled, the TSR can be read or written. Writing to the TSR when the time counter is
disabled will clear the SR[TOF] and/or the SR[TIF]. Writing to TSR with zero is supported, but not
recommended because TSR will read as zero when SR[TIF] or SR[TOF] are set (indicating the time is
invalid).
42.2.2 RTC Time Prescaler Register (RTC_TPR)
Address: 4003_D000h base + 4h offset = 4003_D004h
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R
0
TPR
W
Reset
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
RTC_TPR field descriptions
Field Description
31–16
Reserved
This field is reserved.
This read-only field is reserved and always has the value 0.
TPR Time Prescaler Register
When the time counter is enabled, the TPR is read only and increments every 32.768 kHz clock cycle. The
time counter will read as zero when SR[TOF] or SR[TIF] are set. When the time counter is disabled, the
TPR can be read or written. The TSR[TSR] increments when bit 14 of the TPR transitions from a logic one
to a logic zero.
42.2.3 RTC Time Alarm Register (RTC_TAR)
Address: 4003_D000h base + 8h offset = 4003_D008h
Bit 31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
R
TAR
W
Reset
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
RTC_TAR field descriptions
Field Description
TAR Time Alarm Register
When the time counter is enabled, the SR[TAF] is set whenever the TAR[TAR] equals the TSR[TSR] and
the TSR[TSR] increments. Writing to the TAR clears the SR[TAF].
Register definition
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
1054 NXP Semiconductors