Laptop User Manual

S3C2440A RISC MICROPROCESSOR REAL TIME CLOCK
17-1
17 REAL TIME CLOCK
OVERVIEW
The Real Time Clock (RTC) unit can be operated by the backup battery while the system power is off. The RTC
can transmit 8-bit data to CPU as Binary Coded Decimal (BCD) values using the STRB/LDRB ARM operation. The
data include the time by second, minute, hour, date, day, month, and year. The RTC unit works with an external
32.768 KHz crystal and also can perform the alarm function.
FEATURES
— BCD number: second, minute, hour, date, day, month, and year
— Leap year generator
— Alarm function: alarm interrupt or wake-up from power-off mode
— Year 2000 problem is removed.
— Independent power pin (RTCVDD)
— Supports millisecond tick time interrupt for RTOS kernel time tick.