MA180025 Microchip Technology, MA180025 Datasheet - Page 166

• Manufacturer Part Number: MA180025
• Description: MODULE PLUG-IN PIC18F87J90 PIM
• Manufacturer: Microchip Technology
• Series: PIC®r

Specifications of MA180025

• Accessory Type: Plug-In Module (PIM) - PIC18F87J90
• Product: Microcontroller Modules
• Silicon Manufacturer: Microchip
• Core Architecture: PIC
• Core Sub-architecture: PIC18
• Silicon Core Number: PIC18F
• Silicon Family Name: PIC18FxxJxx
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With/related Products: PICDEM LCD 2 Demonstration Board (DM163030)
• For Use With: DM163030 - KIT DEV PICDEM LCD2
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

PIC18F87J90 FAMILY
15.2.2
As mentioned earlier, the RTCC module is intended to
be clocked by an external Real-Time Clock crystal,
oscillating at 32.768 kHz, but can also be an internal
oscillator. The RTCC clock selection is decided by the
RTCOSC bit (CONFIG3L<1>).
FIGURE 15-4:
15.2.2.1
The RTCC module can be clocked by an external,
32.768 kHz crystal (Timer1 oscillator) or the Internal RC
oscillator, which can be selected in CONFIG3L<1>.
If the external clock is used, the Timer1 oscillator
should be enabled by setting the T1OSCEN bit
(T1CON<3> = 1). If INTRC is providing the clock, the
INTRC clock can be brought out to the RTCC pin by the
RTSECSEL<1:0> bits in the PADCFG register.
15.2.3
This section explains which timer values are affected
when there is a rollover.
• Time of Day: from 23:59:59 to 00:00:00 with a
• Month: from 12/31 to 01/01 with a carry to the
• Day of Week: from 6 to 0 with no carry (see
• Year Carry: from 99 to 00; this also surpasses the
For the day to month rollover schedule, see Table 15-2.
Considering that the following values are in BCD for-
mat, the carry to the upper BCD digit will occur at a
count of 10 and not at 16 (SECONDS, MINUTES,
HOURS, WEEKDAY, DAYS and MONTHS).
DS39933D-page 166
32.768 kHz XTAL
from SOSC
Internal RC
CONFIG 3L<1>
carry to the Day field
Year field
Table 15-1)
use of the RTCC
Note 1:
CLOCK SOURCE
DIGIT CARRY RULES
Real-Time Clock Enable
Writing to the lower half of the MINSEC register resets all counters, allowing fraction of a second
synchronization; clock prescaler is held in Reset when RTCEN =
CLOCK SOURCE MULTIPLEXING
Second
Clock Prescaler
Hour:Minute
1:16384
(1)
Day of Week
module to yield an error of 3 seconds or less per month.
Calibration of the crystal can be done through this
(For further details, see Section 15.2.9 “Calibration”.)
TABLE 15-1:
TABLE 15-2:
Half Second
Note 1:
Clock
Day
09 (September)
12 (December)
11 (November)
02 (February)
01 (January)
10 (October)
08 (August)
03 (March)
06 (June)
04 (April)
05 (May)
07 (July)
Wednesday
Month
Thursday
See Section 15.2.4 “Leap Year”.
0
Saturday
Tuesday
Monday
Sunday
.
Friday
Half second
DAY OF WEEK SCHEDULE
DAY TO MONTH ROLLOVER
SCHEDULE
Day of Week
Month
(1)
 2010 Microchip Technology Inc.
Maximum Day Field
One Second Clock
28 or 29
31
31
30
31
30
31
31
30
31
30
31
0
1
2
3
4
5
6
Year
(1)