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CHAPTER 9 REAL-TIME COUNTER
User’s Manual U19780EJ2V0UD
295
Table 9-2. 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
The HOUR register value is set to 12-hour display when the AMPM bit is “0” and to 24-hour display when the
AMPM bit is “1”.
In 12-hour display, the fifth bit of the HOUR register displays 0 for AM and 1 for PM.
(8) 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)