CHAPTER 15 STANDBY FUNCTION
15.2.2 STOP mode
(1) Setting and operation status of STOP mode
The STOP mode is set by executing the STOP instruction.
Caution Because the standby mode can be released by an interrupt request signal, the standby
mode is released as soon as it is set if there is an interrupt source whose interrupt request
flag is set and interrupt mask flag is reset. When the STOP mode is set, therefore, the
HALT mode is set immediately after the STOP instruction has been executed, the wait time
set by the oscillation stabilization time select register (OSTS) elapses, and then an
operation mode is set.
The operation status in the STOP mode is shown in the following table.
Table 15-3. STOP Mode Operating Status
STOP Mode Operation Status While The Main System Clock Is Running
Item
While the subsystem clock is running
While the subsystem clock is not running
Main system clock
CPU
Oscillation stopped
Operation stopped
Port (output latch)
16-bit timer
Remains in the state existing before the selection of STOP mode.
Operation stopped
8-bit timer
TM50
TM60
Operation enabledNote 1
Operation enabledNote 2
Watch timer
Operation enabledNote 3
Operation stopped
Operation stopped
Watchdog timer
Serial interface
A/D converter
Operation enabled
Operation enabledNote 4
Operation stopped
LCD controller/driver
External interrupt
Operation enabledNote 3
Operation enabledNote 5
Operation stopped
Notes 1. Operation is enabled only when input signal from timer 60 (timer 60 operation is enabled) is selected
as the count clock.
2. Operation is enabled when TMI60 is selected as the count clock.
3. Operation is enabled while the subsystem clock is selected.
4. Operation is enabled only when external clock is selected.
5. Maskable interrupt that is not masked
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User’s Manual U15075EJ1V0UM00
NEC [ NEC ]
