Toshiba TXZ+ Series Reference Manual page 20

setup (an external oscillation/external clock input → an internal oscillation)
(3) f
OSC
As a f setup, the example of switching procedure to the internal oscillation (IHOSC1) from an external
OSC
oscillation (EHOSC) or an external clock input (EHCLKIN) is shown below.
[CGOSCCR]<EOSCEN[1:0]> = 01 or 10
[CGOSCCR]<OSCSEL> = 1
[CGOSCCR]<OSCF> = 1
1 [CGWUPHCR]<WUCLK> = 0
2 [CGWUPHCR]<WUPT[15:4]> = 0x03C
3 [CGOSCCR]<IHOSC1EN> = 1
4 [CGWUPHCR]<WUON> = 1
5 [CGWUPHCR]<WUEF> is read.
[CGOSCCR]<OSCSEL> = 0
6
7 [CGOSCCR]<OSCF> is read.
8 [CGOSCCR]<EOSCEN[1:0]> = 00
<< The state before switching >>
Selection of an external oscillator of operation is an external oscillator
(EHOSC) or external clock input.
The high speed oscillation selection for f
The high speed oscillation selection status for f
(EHOSC).
<< The example of switching procedure >>
Set the warming-up clock selection to internal high speed oscillator 1
(IHOSC1).
Set the high speed oscillation warming-up timer setting value of
163.4μs (= 0x3C) or more.
An internal high speed oscillator 1 oscillates.
Start the high speed oscillation warming-up timer
Wait until an warming-up timer status flag becomes ends (= 1).
Set the high speed oscillation selection for f
oscillator1 (IHOSC1).
It waits until the high speed oscillation selection status for f
becomes an inside (= 0).
Set the selection of an external oscillator operation to unused.
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TMPM3H Group(1)
Clock Control and Operation Mode
is the exterior (EHOSC).
OSC
is the exterior
OSC
to internal high-speed
OSC
TXZ+ Family
OSC
2022-05-10
Rev. 1.3