Microchip Technology AC164139 Data Sheet

 2010 Microchip Technology Inc.

DS39969B-page 285

The Real-Time Clock and Calendar (RTCC) provides a
function that can be calibrated.
Key features of the RTCC module are:
• Operates in Sleep mode
• Provides hours, minutes and seconds using 

24-hour format

• Visibility of half of one second period
• Provides calendar – weekday, date, month and 

year

• Alarm configurable for half a second, one 

second,10 seconds, one minute, 10 minutes, one 
hour, one day, one week, one month or one year

• Alarm repeat with decrementing counter
• Alarm with indefinite repeat chime
• Year, 2000 to 2099, leap year correction
• BCD format for smaller software overhead
• Optimized for long-term battery operation
• User calibration of the 32.768 kHz clock 

crystal/32K INTRC frequency with periodic 
auto-adjust
- Calibration to within ±2.64 seconds error per 

month

- Calibrates up to 260 ppm of crystal error

This data sheet summarizes the features
of this group of PIC24F devices. It is not
intended to be a comprehensive reference
source. For more information, refer to the
“PIC24F Family Reference Manual”,
Section 29. “Real-Time Clock and
Calendar (RTCC)” (DS39696). The
information in this data sheet
supersedes the information in the FRM.

RTCC Prescalers

RTCC Timer

Comparator

Compare Registers

Repeat Counter

YEAR

MTHDY

WKDYHR

MINSEC

ALMTHDY

ALWDHR

ALMINSEC

with Masks

RTCC Interrupt Logic

RCFGCAL

ALCFGRPT

Alarm

Event

32.768 kHz Input
from SOSC

0.5s

Alarm Pulse

RTCC Interrupt

RTCVAL

ALRMVAL

RTCC Pin

RTCOE