SH7261 Datasheet, PDF (692/1348 Pages) Renesas Technology Corp – 32-Bit RISC Microcomputer SuperHTM RISC engine Family / SH7260 Series

Section 15 Realtime Clock (RTC)
Initial
Bit Bit Name Value
3
RTCEN
1
2
ADJ
0
1
RESET
0
0
START
1
R/W Description
R/W Crystal Oscillator Control
Controls the operation of the crystal oscillator for the
RTC.
0: Halts the crystal oscillator for the RTC.
1: Runs the crystal oscillator for the RTC.
R/W 30-Second Adjustment
When 1 is written to the ADJ bit, times of 29 seconds or
less will be rounded to 00 seconds and 30 seconds or
more to 1 minute. The divider circuit (RTC prescaler
and R64CNT) will be simultaneously reset. This bit
always reads 0.
Important: When using this bit, see section 15.5.5,
Procedure for Setting the 30-Second Adjustment
Function.
0: Runs normally.
1: 30-second adjustment.
R/W Reset
Writing 1 to this bit initializes the divider circuit. In this
case, the RESET bit is automatically reset to 0 after 1 is
written to and the divider circuit (RTC prescaler and
R64CNT) is reset. Thus, there is no need to write 1 to
this bit. This bit is always read as 0.
0: Runs normally.
1: Divider circuit is reset.
R/W Start Bit
Halts and restarts the counter (clock).
0: Second/minute/hour/day/week/month/year counter
halts.
1: Second/minute/hour/day/week/month/year counter
runs normally.
Note: The 64-Hz counter always runs unless stopped
with the RTCEN bit.
Rev. 2.00 Sep. 07, 2007 Page 660 of 1312
REJ09B0320-0200