upd78f0114hgb-8es-a Renesas Electronics Corporation., upd78f0114hgb-8es-a Datasheet - Page 375

• Manufacturer Part Number: upd78f0114hgb-8es-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

Note 1
If supply voltage fluctuation is 50 ms or less in vicinity of LVI detection voltage
Notes 1.
2.
3.
If reset is generated again during this period, initialization processing is not started.
A flowchart is shown on the next page.
Waiting for the oscillation stabilization time is not required when the external RC oscillation clock is
selected as the high-speed system clock by the option byte.
switched without reading the OSTC value.
No
Figure 21-6. Example of Software Processing After Release of Reset (1/2)
50 ms has passed?
Change CPU clock
Check stabilization
Checking cause
(TMIFH1 = 1?)
(set to 50 ms)
of oscillation
of reset
Initialization
processing
Start timer
Reset
LVI
Yes
Note 2
CHAPTER 21 LOW-VOLTAGE DETECTOR
User’s Manual U16961EJ4V0UD
; The internal oscillation
;
;
;
;
;
;
signal is generated
The cause of reset (power-on-clear, WDT, LVI, or clock monitor)
can be identified by the RESF register.
8-bit timer H1 can operate with the
Source: f
(f
Check the stabilization of oscillation of the high-speed system clock
by using the OSTC register
Change the CPU clock from the
high-speed system clock.
TMIFH1 = 1: Interrupt request is generated.
Initialization of ports
R
:
internal oscillation
R
(480 kHz (MAX.))/2
clock oscillation frequency)
clock is set as the CPU clock when the reset
Note 3
Therefore, the CPU clock can be
7
.
internal oscillation
compare value 200 = 53 ms
internal oscillation
clock to the
clock.
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