PIC18F44J50-I Datasheet, PDF (237/562 Pages) Microchip Technology – 28/44-Pin, Low-Power, High-Performance USB Microcontrollers

PIC18F46J50 FAMILY
17.1.4 RTCEN BIT WRITE
An attempt to write to the RTCEN bit while
RTCWREN = 0 will be ignored. RTCWREN must be
set before a write to RTCEN can take place.
Like the RTCEN bit, the RTCVALH and RTCVALL
registers can only be written to when RTCWREN = 1.
A write to these registers, while RTCWREN = 0, will be
ignored.
FIGURE 17-2:
TIMER DIGIT FORMAT
Year
Month
17.2 Operation
17.2.1 REGISTER INTERFACE
The register interface for the RTCC and alarm values is
implemented using the Binary Coded Decimal (BCD)
format. This simplifies the firmware, when using the
module, as each of the digits is contained within its own
4-bit value (see Figure 17-2 and Figure 17-3).
Day
Day Of Week
0-9
0-9
0-1
0-9
0-3
0-9
0-6
Hours
(24-hour format)
0-2
0-9
Minutes
0-5
0-9
Seconds
0-5
0-9
1/2 Second Bit
(binary format)
0/1
FIGURE 17-3:
ALARM DIGIT FORMAT
Month
Hours
(24-hour format)
0-2
0-9
0-1
0-9
Minutes
0-5
0-9
Day
0-3
0-9
Seconds
0-5
0-9
Day Of Week
0-6
 2011 Microchip Technology Inc.
DS39931D-page 237