Datasheet

78K0/Kx2-L CHAPTER 10 REAL-TIME COUNTER
R01UH0028EJ0400 Rev.4.00 380
Sep 27, 2010
Table 10-2. Displayed Time Digits
24-Hour Display (AMPM bit = 1) 12-Hour Display (AMPM bit = 0)
Time HOUR Register Time HOUR Register
0 00H 0 a.m. 12H
1 01H 1 a.m. 01H
2 02H 2 a.m. 02H
3 03H 3 a.m. 03H
4 04H 4 a.m. 04H
5 05H 5 a.m. 05H
6 06H 6 a.m. 06H
7 07H 7 a.m. 07H
8 08H 8 a.m. 08H
9 09H 9 a.m. 09H
10 10H 10 a.m. 10H
11 11H 11 a.m. 11H
12 12H 0 p.m. 32H
13 13H 1 p.m. 21H
14 14H 2 p.m. 22H
15 15H 3 p.m. 23H
16 16H 4 p.m. 24H
17 17H 5 p.m. 25H
18 18H 6 p.m. 26H
19 19H 7 p.m. 27H
20 20H 8 p.m. 28H
21 21H 9 p.m. 29H
22 22H 10 p.m. 30H
23 23H 11 p.m. 31H
(9) 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 clocks (32.768 kHz) 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. If a value outside the range is
set, the register value returns to the normal value after 1 period.
DAY can be set by an 8-bit memory manipulation instruction.
Reset signal generation clears this register to 01H.