SH7708 Datasheet, PDF (342/625 Pages) Renesas Technology Corp – SuperH™ RISC engine

12.2.16 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 not initialized by a manual reset or in standby mode, and retains
its contents.
Bit: 7
Bit name: PEF
Initial value: 0
R/W: R/W
6
5
4
3
2
1
0
PES2 PES1 PES0 RTCEN ADJ RESET START
0
0
0
1
0
0
1
R/W R/W R/W R/W R/W R/W R/W
Bit 7—Periodic Interrupt Flag (PEF): Indicates interrupt generation with the period designated by
the PES bits. When set to 1, PEF generates periodic interrupts.
Bit 7: PEF
0
1
Description
Interrupts not generated with the period designated by the PES bits.
Clearing condition: When 0 is written to PEF
(Initial
value)
Interrupts generated with the period designated by the PES bits.
Setting condition: When 1 is written to PEF
Bits 6–4—Periodic Interrupt Flags (PES2–PES0): These bits specify the periodic interrupt.
Bit 6: PES2 Bit 5: PES1 Bit 4: PES0 Description
0
0
0
No periodic interrupts generated (Initial value)
1
Periodic interrupt generated every 1/256 second
1
0
Periodic interrupt generated every 1/64 second
1
Periodic interrupt generated every 1/16 second
1
0
0
Periodic interrupt generated every 1/4 second
1
Periodic interrupt generated every 1/2 second
1
0
Periodic interrupt generated every 1 second
1
Periodic interrupt generated every 2 seconds
Bit 3—RTCEN: Controls the operation of the crystal oscillator for the RTC.
328