PIC18F25J50 MICROCHIP [Microchip Technology], PIC18F25J50 Datasheet - Page 225

• Manufacturer Part Number: PIC18F25J50
• Description: 28/44-Pin, Low-Power, High-Performance USB Microcontrollers with nanoWatt XLP Technology
• Manufacturer: MICROCHIP [Microchip Technology]

17.0
The key features of the Real-Time Clock and Calendar
(RTCC) module are:
• Time: hours, minutes and seconds
• 24-hour format (military time)
• Calendar: weekday, date, month and year
• Alarm configurable
• Year range: 2000 to 2099
• Leap year correction
• BCD format for compact firmware
• Optimized for low-power operation
• User calibration with auto-adjust
• Calibration range: 2.64 seconds error per month
• Requirements: external 32.768 kHz clock crystal
• Alarm pulse or seconds clock output on RTCC pin
FIGURE 17-1:
 2011 Microchip Technology Inc.
from Timer1 Oscillator
32.768 kHz Input
REAL-TIME CLOCK AND
CALENDAR (RTCC)
Internal RC
RTCC BLOCK DIAGRAM
Alarm
Event
RTCC Clock Domain
Compare Registers
RTCC Prescalers
Repeat Counter
RTCC Timer
Comparator
with Masks
0.5s
RTCC Interrupt Logic
PIC18F46J50 FAMILY
The RTCC module is intended for applications where
accurate time must be maintained for an extended
period with minimum to no intervention from the CPU.
The module is optimized for low-power usage in order
to provide extended battery life while keeping track of
time.
The module is a 100-year clock and calendar with auto-
matic leap year detection. The range of the clock is
from 00:00:00 (midnight) on January 1, 2000 to
23:59:59 on December 31, 2099. Hours are measured
in 24-hour (military time) format. The clock provides a
granularity of one second with half-second visibility to
the user.
CPU Clock Domain
ALRMVAL
ALRMRPT
RTCCFG
RTCVAL
RTCOE
Alarm Pulse
RTCC Interrupt
ALMINSEC
ALMTHDY
WKDYHR
ALWDHR
MINSEC
MTHDY
YEAR
DS39931D-page 225
RTCC Pin