Watchdog Timer Operation In Halt Mode (When "Low-Speed Internal Oscillator Can Be Stopped By Software" Is Selected By Option Byte) - NEC 78K0S/KB1+ User Manual

9.4.4 Watchdog timer operation in HALT mode (when "low-speed internal oscillator can be stopped by
software" is selected by option byte)
The watchdog timer stops counting during HALT instruction execution regardless of whether the operation clock of
the watchdog timer is the system clock (f
counting is started again using the operation clock before the operation was stopped. At this time, the counter is not
cleared to 0 but holds its value.
Normal operation
CPU operation
f
CPU
f or f
X RL
Watchdog timer
Operating
CHAPTER 9 WATCHDOG TIMER
) or low-speed internal oscillation clock (f
X
Figure 9-8. Operation in HALT Mode
HALT
Operation stopped
User's Manual U17446EJ3V1UD
). After HALT mode is released,
RL
Normal operation
Operating
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