upd78f0134hgka1-9et-a Renesas Electronics Corporation., upd78f0134hgka1-9et-a Datasheet - Page 233

• Manufacturer Part Number: upd78f0134hgka1-9et-a
• Description: 8-bit Single-chip Microcontrollers
• Manufacturer: Renesas Electronics Corporation.

Notes 1.
Remarks 1. f
Watchdog timer clock
source
Operation after reset
Operation mode selection
Features
2.
2. f
As long as power is being supplied, internal oscillator oscillation cannot be stopped (except in the reset
period).
The conditions under which clock supply to the watchdog timer is stopped differ depending on the
clock source of the watchdog timer.
<1> If the clock source is f
<2> If the clock source is f
R
XP
: Internal oscillation clock oscillation frequency
: High-speed system clock oscillation frequency
conditions.
conditions.
Table 10-2. Option Byte Setting and Watchdog Timer Operation Mode
When f
In HALT/STOP mode
During oscillation stabilization time
If the CPU clock is f
In HALT/STOP mode
XP
Fixed to f
Operation starts with the maximum interval
(2
The interval can be changed only once.
The watchdog timer cannot be stopped.
is stopped
18
/f
Internal Oscillator Cannot Be Stopped
R
).
R
Note 1
CHAPTER 10 WATCHDOG TIMER
XP
.
XP
R
and if f
, clock supply to the watchdog timer is stopped under the following
User’s Manual U16899EJ3V0UD
, clock supply to the watchdog timer is stopped under the following
R
is stopped by software before execution of the STOP instruction
Option Byte
Operation starts with maximum interval
(2
The clock selection/interval can be changed
only once.
The watchdog timer can be stopped in
standby mode
Selectable by software (f
When reset is released: f
18
/f
Internal Oscillator Can Be Stopped by
R
).
Note 2
Software
.
XP
R
, f
R
or stopped)
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