HD6417751 Datasheet, PDF (303/1105 Pages) Renesas Technology Corp – SuperH RISC engine

Section 11 Realtime Clock (RTC)
11.1 Overview
The SH7751 Series includes an on-chip realtime clock (RTC) and a 32.768 kHz crystal oscillator
for use by the RTC.
11.1.1 Features
The RTC has the following features.
• Clock and calendar functions (BCD display)
Counts seconds, minutes, hours, day-of-week, days, months, and years.
• 1 to 64 Hz timer (binary display)
The 64 Hz counter register indicates a state of 64 Hz to 1 Hz within the RTC frequency divider
• Start/stop function
• 30-second adjustment function
• Alarm interrupts
Comparison with second, minute, hour, day-of-week, day, month, or year (SH7751R only) can
be selected as the alarm interrupt condition
• Periodic interrupts
An interrupt period of 1/256 second, 1/64 second, 1/16 second, 1/4 second, 1/2 second, 1
second, or 2 seconds can be selected
• Carry interrupt
Carry interrupt function indicating a second counter carry, or a 64 Hz counter carry when the
64 Hz counter is read
• Automatic leap year adjustment
Rev. 3.0, 04/02, page 263 of 1064