Block Diagram; External Signal Description; Register Definition - ROHS MC9S08QE128 Reference Manual

13.1.8

Block Diagram

The block diagram for the RTC module is shown in
LPO
OSCOU
ERCLK
T
IRCLK
BACKGROUND
MODE
RTCLKS[0]
13.2

External Signal Description

The RTC does not include any off-chip signals.
13.3 Register Definition
The RTC includes a status and control register, an 8-bit counter register, and an 8-bit modulo register.
Refer to the direct-page register summary in the memory section of this data sheet for the absolute address
assignments for all RTC registers.This section refers to registers and control bits only by their names and
relative address offsets.
Table 13-1 is a summary of RTC registers.
Name
RTCSC
RTCCNT
RTCMOD
Freescale Semiconductor
CLOCK
SOURCE
SELECT
RTCLKS
RTCPS
RTC
PRESCALER
CLOCK
DIVIDE-BY
Figure 13-2. Real-Time Counter (RTC) Block Diagram
Table 13-1. RTC Register Summary
7
R
RTIF
W
R
W
R
W
MC9S08QE128 MCU Series Reference Manual, Rev. 2
Figure 13-2.
V
8-BIT MODULO
(RTCMOD)
8-BIT COMPARATOR
8-BIT COUNTER
(RTCCNT)
...It is a shame! It cannot count external events either!
6 5 4
RTCLKS RTIE
Clock Source Select
RTCCNT
RTCMOD
Real-Time Counter (S08RTCV1)
DD
D Q
RTIF
E
R
RTIE
Write 1 to
RTIF
3 2
RTCPS
RTC
INTERRUPT
REQUEST
1 0
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