Philips P89LPC903 - Manual (Page 54)

Philips Semiconductors User’s Manual - Preliminary -
P89LPC901/902/903
REAL-TIME CLOCK/SYSTEM TIMER
2003 Dec 8
54
Figure 6-2: RTCCON Register
RTCCON
Address: D1h
Not bit addressable
Reset Source(s): Power-up only
Reset Value: 011xxx00B
BIT
SYMBOL FUNCTION
RTCCON.7 RTCF Real-time Clock Flag. This bit is set to ’1’ when the 23-bit Real-time clock reaches a count
of ’0’. It can be cleared in software.
RTCCON.6-5 RTCS1-0 Real-time Clock source select (see Table ,Table ).
RTCCON.4-2 - Reserved for future use. Should not be set to 1 by user programs.
RTCCON.1 ERTC Real-time Clock interrupt enable. The Real-time clock shares the same interrupt as the
watchdog timer. Note that if the user configuration bit WDTE (UCFG1.7) is ’0’, the
watchdog timer can be enabled to generate an interrupt. Users can read the RTCF
(RTCCON.7) bit to determine whether the Real-time clock caused the interrupt.
RTCCON.0 RTCEN Real-time Clock enable. The Real-time clock will be enabled if this bit is ’1’. Note that this
bit will not Power down the Real-time Clock. The RTCPD bit (PCONA.7) if set, will Power
down and disable this block regardless of RTCEN.
7 6 5 4 3 2 1 0
RTCF RTCS1 RTCS0 - - - ERTC RTCEN