UPD78F0138 NEC, UPD78F0138 Datasheet - Page 395

• Manufacturer Part Number: UPD78F0138
• Description: (UPD78xxxx) 8-Bit Single-Chip Microcontrollers
• Manufacturer: NEC

Ring-OSC clock
Ring-OSC clock
Note The port pins become high impedance, except for P130, which is set to low-level output.
Watchdog timer
Note The port pins become high impedance, except for P130, which is set to low-level output.
Caution A watchdog timer internal reset resets the watchdog timer.
X1 input clock
X1 input clock
reset signal
reset signal
CPU clock
CPU clock
overflow
Port pin
RESET
Internal
Port pin
Internal
Normal operation
Normal operation
Figure 20-3. Timing of Reset Due to Watchdog Timer Overflow
Figure 20-2. Timing of Reset by RESET Input
CHAPTER 20 RESET FUNCTION
Delay
User’s Manual U16228EJ2V0UD
(Oscillation stop)
(Oscillation stop)
Reset period
Reset period
Delay
Operation stop
Operation stop
(17/f
(17/f
R
R
)
)
Hi-Z
Hi-Z
Note
Note
Normal operation
(Reset processing, Ring-OSC clock)
Normal operation
(Reset processing, Ring-OSC clock)
395