SH7706 Datasheet, PDF (402/749 Pages) Renesas Technology Corp – Renesas 32-Bit RISC Microcomputer SuperH™ RISC engine Family/SH7700 Series

Section 13 Realtime Clock (RTC)
13.3.16 RTC Control Register 2 (RCR2)
The RTC control register 2 (RCR2) is an 8-bit read/write register for periodic interrupt control, 30-
second adjustment ADJ, divider circuit RESET, and RTC count start/stop control. It is initialized
to H'09 by a power-on reset. It is initialized except for RTCEN and START by a manual reset. It is
not initialized in standby mode, and retains its contents.
Bit Bit Name Initial Value R/W Description
7
PEF
0
R/W Periodic Interrupt Flag
Indicates interrupt generation with the period
designated by the PES bits. When set to 1, PEF
generates periodic interrupts.
0: Interrupts not generated with the period
designated by the PES bits.
[Clearing condition]
When 0 is written to PEF
1: Interrupts generated with the period designated by
the PES bits.
[Setting condition]
When 1 is written to PEF
6
PES2
0
5
PES1
0
4
PES0
0
R/W Periodic Interrupt Flags
R/W These bits specify the periodic interrupt.
R/W 000: No periodic interrupts generated
001: Periodic interrupt generated every 1/256
second
010: Periodic interrupt generated every 1/64 second
011: Periodic interrupt generated every 1/16 second
100: Periodic interrupt generated every 1/4 second
101: Periodic interrupt generated every 1/2 second
110: Periodic interrupt generated every 1 second
111: Periodic interrupt generated every 2 seconds
3
RTCEN 1
R/W 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.
Rev. 5.00 May 29, 2006 page 354 of 698
REJ09B0146-0500