Block Diagram; Basic Configuration; Functional Description; Figure 6.11-1 Rtc Block Diagram - Nuvoton ISD94124BYI Technical Reference Manual

6.11.3 Block Diagram

The RTC block diagram is shown below.
INIT
INIT
RWEN
RWEN
LEAPYEAR
LEAPYEAR
24H/12H
CLKFMT
WEEKDAY
WEEKDAY
RTC_CLK
LIRC
1
LXT
0
RTCSEL
(CLK_CLKSEL3[8])

6.11.4 Basic Configuration


Clock source configuration
–
The RTC controller clock source is enabled by RTCCKEN (APBCLK0[1]) and RTC
Time Counter source is selected by CLK_CLKSEL3[8], the clock source can be LXT or
LIRC.

Pin configuration
Group Pin Name
X32_OUT
X32
X32_IN

6.11.5 Functional Description

6.11.5.1 RTC Initiation
When a RTC block is power-on, RTC is at reset state. User has to write a number 0xa5eb1357 to
RTC initial register INIT(RTC_INIT[31:0]) to make RTC leaving reset state. Once the
INIT(RTC_INIT[31:0]) register is written as 0xa5eb1357, the RTC will be in normal active state
permanently. User can read INIT[0](RTC_INIT[0]) to check the RTC is at normal active state or
reset state.
Sep 9, 2019
ISD94100 Series Technical Reference Manual
Time Alarm
Time Alarm Calendar
Mask Register
Register Alarm Register
(RTC_TAMSK)
(RTC_TALM) (RTC_CALM)
Calendar
Time Loading
Loading
Register
Register
Operation
(RTC_TIME)
(RTC_CAL)
1/128 change
1/64 change
1/32 change
RTC Time Counter
1/16 change
Control Unit
1/8 change
1/4 change
Frequency
1/2 change
Compensation
1 change
TICK (RTC_TICK[2:0])
Frequency
Compensation
Register
(RTC_FREQADJ)

Figure 6.11-1 RTC Block Diagram

GPIO
PC.0
PC.1
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Calendar Alarm
Mask Register
(RTC_CAMSK)
ALMIEN (RTC_INTEN[0])
Compare
ALMIF (RTC_INTSTS[0])
(sec)
111
110
TICKIEN (RTC_INTEN[1])
101
100
011
TICKIF (RTC_INTSTS[1])
010
001
000
Alarm Interrupt
Wakeup CPU from
Power-down mode
Tick Interrupt
MFP
MFP2
MFP2
Rev1.09