Stop Mode - NEC 78K0S/KU1+ User Manual

11.2.2 STOP mode

(1) STOP mode setting and operating statuses
The STOP mode is set by executing the STOP instruction.
Caution Because an interrupt request signal is used to clear the standby mode, if there is an interrupt
source with the interrupt request flag set and the interrupt mask flag reset, the standby
mode is immediately cleared if set. Thus, in the STOP mode, the normal operation mode is
restored after the STOP instruction is executed and then the operation is stopped for the
duration of 34
oscillation stabilization time select register (OSTS) has elapsed when crystal/ceramic
oscillation is used).
The operating statuses in the STOP mode are shown below.
Setting of STOP Mode
Item
System clock
CPU
Port (latch)
16-bit timer/event counter 00
8-bit timer Sets count clock to f
H1
Sets count clock to f
Watchdog "System clock" selected as
timer operating clock
"Low-speed internal oscillation
clock" selected as operating
clock
A/D converter
Power-on-clear circuit
Low-voltage detector
External interrupt
Note "Cannot be stopped" or "Stopped by software" is selected for low-speed internal oscillator by the option byte
(for the option byte, see CHAPTER 15 OPTION BYTE).
CHAPTER 11 STANDBY FUNCTION
µ
s (TYP.) (after an additional wait time for stabilizing oscillation set by the
Table 11-4. Operating Statuses in STOP Mode
Low-Speed Internal
Oscillator cannot be
Note
stopped
Oscillation stops.
Operation stops.
Holds status before STOP mode was set.
Operation stops.
12
to f /2 Operation stops.
XP XP
7
/2 Operable
RL
Setting disabled.
Operable
(Operation continues)
Operation stops.
Always operates.
Operable
Operable
User's Manual U18172EJ2V0UD
Low-Speed Internal Oscillator can be stopped
When Low-Speed Internal
.
Oscillation Continues
Operable
Operation stops.
Operation stops.
Note
.
When Low-Speed Internal
Oscillation Stops
Operation stops.
183