RL78/F13, F14 CHAPTER 9 REAL-TIME CLOCK
R01UH0368EJ0210 Rev.2.10 670
Dec 10, 2015
9.3.11 Day count register (DAY)
The DAY register is an 8-bit register that takes a value of 1 to 31 (decimal) and indicates the count value of days.
It counts up when the hour counter overflows.
This counter counts as follows.
01 to 31 (January, March, May, July, August, October, December)
01 to 30 (April, June, September, November)
01 to 29 (February, leap year)
01 to 28 (February, normal year)
When data is written to this register, it is written to a buffer and then to the counter up to 2 operating clocks (f
RTC)
later. Even if the hour count register overflows while this register is being written, this register ignores the overflow
and is set to the value written. Set a decimal value of 01 to 31 to this register in BCD code.
Set the DAY register by an 8-bit memory manipulation instruction.
Reset signal generation clears this register to 01H.
Figure 9-12. Format of Day Count Register (DAY)
Address: FFF96H After reset: 01H R/W
Symbol 7 6 5 4 3 2 1 0
DAY 0 0 DAY20 DAY10 DAY8 DAY4 DAY2 DAY1
Caution When it reads or writes from/to the register while the counter is in operation (RTCE = 1), see
9.4.3 Reading/writing real-time clock and follow the described procedures.