Toshiba H1 Series Data Book page 577

3.21 Real time clock (RTC)
3.21.1 Function description for RTC
1) Clock function (hour, minute, second)
2) Calendar function (month and day, day of the week, and leap year)
3) 24 or 12-hour (AM/PM) clock function
4) +/- 30 second adjustment function (by software)
5) Alarm function (Alarm output)
6) Alarm interrupt generate
3.21.2 Block diagram
32 KHz
Clock
Carry hold
(1s)
Adjust
RD
Note1: The Christian era year column:
This product has year column toward only lower two columns. Therefore the next year
in 99 works as 00 years. In system to use it, please manage upper two columns with
the system side when handle year column in the Christian era.
Note2: Leap year:
A leap year is the year, which is divisible with 4, but the year, which there is exception,
and is divisible with 100, is not a leap year. However, the year is divisible with 400, is a
leap year. But there is not this product for the correspondence to the above exception.
Because there are only with the year that is divisible with 4 as a leap year, please cope
with the system side if this function is problem.
Divider
1 Hz Clock
Alarm Register
Comparator
Clock
Address
Bus
Internal data bus
R/W Control
WR D0~D7 Address
Figure 3.21.1 RTC block diagram
92CZ26A-574
16 Hz Clock
Alarm
Selector
ALARM
TMP92CZ26A
ALARM
INTRTC