Renesas RL78 Series User Manual

RL78/F13, F14 CHAPTER 9 REAL-TIME CLOCK
R01UH0368EJ0210 Rev.2.10 656
Dec 10, 2015
CHAPTER 9 REAL-TIME CLOCK
9.1 Functions of Real-time Clock
The real-time clock has the following features.
 Having counters of year, month, week, day, hour, minute, and second, and can count up to 99 years.
 Constant-period interrupt function (period: 0.5 seconds, 1 second, 1 minute, 1 hour, 1 day, 1 month)
 Alarm interrupt function (alarm: week, hour, minute)
 Pin output function of 1 Hz
 Watch error correction register
Caution The count of year, month, week, day, hour, minutes and second can only be performed when a
subsystem clock (f
SUB = 32.768 kHz), high-speed on-chip oscillator (fIH = 4 MHz or 8 MHz), or high-speed
system clock (f
MX = 4 MHz, 8 MHz, 4.19 MHz, 8.38 MHz) is selected as the operation clock of the real-
time clock. When selecting the high-speed on-chip oscillator or high-speed system clock, use the RTC
clock select register (RTCCL) to select the clock and the frequency divisor.
9.2 Configuration of Real-time Clock
The real-time clock includes the following hardware.
Table 9-1. Configuration of Real-time Clock
Item Configuration
Counter Internal counter (16 bits)
Control registers Peripheral enable register 0 (PER0)
Operation speed mode control register (OSMC)
Timer input select register 1 (TIS1)
Timer input select register 2 (TIS2)
RTC clock select register (RTCCL)
Real-time clock control register 0 (RTCC0)
Real-time clock control register 1 (RTCC1)
Second count register (SEC)
Minute count register (MIN)
Hour count register (HOUR)
Day count register (DAY)
Week count register (WEEK)
Month count register (MONTH)
Year count register (YEAR)
Watch error correction register (SUBCUD)
16-bit watch error correction register (SUBCUDW)
Alarm minute register (ALARMWM)
Alarm hour register (ALARMWH)
Alarm week register (ALARMWW)

Renesas RL78 Series Specifications

General

Brand	Renesas
Model	RL78 Series
Category	Computer Hardware
Language	English