mc68hc908lj24 Freescale Semiconductor, Inc, mc68hc908lj24 Datasheet - Page 230

• Manufacturer Part Number: mc68hc908lj24
• Description: M68hc08 Microcontrollers
• Manufacturer: Freescale Semiconductor, Inc

Real Time Clock (RTC)
12.9.2 Stop Mode
12.10 RTC Registers
Data Sheet
230
For continuous RTC operation in stop mode, the oscillator stop mode
enable bit (STOP_XCLKEN in CONFIG2 register) must be set before
executing the STOP instruction. When STOP_XCLKEN is set,
CGMXCLK continues to drive the RTC module, and any enabled CPU
interrupt request from the RTC can bring the MCU out of stop mode.
If STOP_XCLKEN bit is cleared, the RTC module is inactive after the
execution of a STOP instruction. The STOP instruction does not affect
RTC register states. RTC module operation resumes after an external
interrupt. To further reduce power consumption, the RTC module should
be powered-down by clearing the RTCE bit before executing the STOP
instruction.
The RTC module has fifteen memory-mapped registers:
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RTC calibration control register (RTCCOMR)
RTC calibration data register (RTCCDAT)
RTC control register 1 (RTCCR1)
RTC control register 2 (RTCCR2)
RTC status register (RTCSR)
Alarm minute and hour registers (ALMR and ALHR)
Second register (SECR)
Minute register (MINR)
Hour register (HRR)
Day register (DAY)
Month register (MTHR)
Year register (YRR)
Day of the week register (DOWR)
Chronograph data register (CHRR)
Real Time Clock (RTC)
MC68HC908LJ24/LK24 — Rev. 2.1
Freescale Semiconductor