Datasheet

CLOCK
DIVIDER
BUS CLK
LPO CLK
EXT CLK
RTCLKS RTCPS
16-bit counter
16-bit modulo
16-bit modulo
16-bit comparator
16-bit latch
D Q
R
1
RTIF
Write 1 to RTIF
RTC
INTERRUPT
REQUEST
RTIE
RTCCNT
RTCMOD
OUTPUT
TOGLE
D Q
Q
BUS CLK
RTCO
Figure 14-1. Real-time counter (RTC) block diagram
14.3 External signal description
RTCO is the output of RTC. After MCU reset, the RTC_SC1[RTCO] is set to high.
When the counter is overflow, the output is toggled.
14.4 Register definition
The RTC includes a status and control register, a 16-bit counter register, and a 16-bit
modulo register.
RTC memory map
Absolute
address
(hex)
Register name
Width
(in bits)
Access Reset value
Section/
page
306A RTC Status and Control Register 1 (RTC_SC1) 8 R/W 00h 14.4.1/396
306B RTC Status and Control Register 2 (RTC_SC2) 8 R/W 00h 14.4.2/397
306C RTC Modulo Register: High (RTC_MODH) 8 R/W 00h 14.4.3/398
306D RTC Modulo Register: Low (RTC_MODL) 8 R/W 00h 14.4.4/398
306E RTC Counter Register: High (RTC_CNTH) 8 R 00h 14.4.5/399
306F RTC Counter Register: Low (RTC_CNTL) 8 R 00h 14.4.6/399
Chapter 14 Real-time counter (RTC)
MC9S08PA60 Reference Manual, Rev. 1, 9/2012
Freescale Semiconductor, Inc. 395