Renesas SH7709S Manual Do Utilizador

Rev. 5.00, 09/03, page 421 of 760

Bits 6 to 4—Periodic Interrupt Flags (PES2-PES0): Specify the periodic interrupt.

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

RTCEN: Controls the operation of the crystal oscillator for the RTC.

0

Crystal oscillator for RTC is halted

1

Crystal oscillator for RTC runs

(Initial value)

Second Adjustment (ADJ): 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 is always read as 0. The maximum
duration between when the ADJ bit is set to 1 and when the new setting is reflected in the readout
value from the seconds counter (RSECCNT) is approximately 91.6 µs (when a 32.768 kHz quartz
oscillator is connected to the EXTAL2 pin).

0

Runs normally

(Initial value)

1 (Write)

30-second adjustment

Reset (RESET): When 1 is written, initializes the divider circuit (RTC prescaler and

R64CNT). This bit is always read as 0.

0

Runs normally 

(Initial value)

1 (Write)

Divider circuit is reset