NO:
W90P710 Programming Guide
VERSION:
2.0
PAGE:
181
The above information is the exclusive intellectual property of Winbond Electronics and shall not be disclosed, distributed or reproduced without permission
from Winbond.
Table No.: 2005-W90P710-11-A
15 Real Time Clock (RTC)
15.1 Overview
Real Time Clock (RTC) block can be operated by independent power supply while the system
power is off. The RTC block utilizes an external crystal to generate 32.768KHz clock. The RTC can
transmit data to CPU as BCD values. The data include the time by second, minute, hour and the date
by day, month, year. In addition, to reach better frequency accuracy, the RTC counter can be
adjusted by software.
The W90P710 Real Time Clock has the following features :
z
Time counter (second, minute, hour) and calendar counter (day, month, year)
z
Alarm register (second, minute, hour, day, month, year)
z
12/24 hour mode selectable
z
Recognize leap year automatically
z
Day of the week counter
z
Frequency compensate register(FCR)
z
Beside FCR, all clock and alarm data expressed in BCD code
z
Support tick time interrupt