Stop Mode; Stop Mode Operation Status - NEC switch User Manual

12.2.2 STOP mode

(1) Setting and operation status of STOP mode
The STOP mode is set by executing the STOP instruction.
Cautions 1. When the STOP mode is set, the X2 pin is internally pulled up to V
current leakage of the crystal oscillator block. Therefore, do not use the STOP mode
in a system where an external clock is used as the system clock.
2. 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 the operation mode is set.
The operation status in the STOP mode is shown in the following table.
Item
Clock generator
CPU
Port (output latch)
8-bit timer 00 (TM00)
8-bit timer/event counter 01 (TM01)
Watchdog timer
USB function
Serial interface 10
Key return
External interrupt
Notes 1. Operation is enabled only when TI01 is selected as the count clock.
2. Operation is enabled only when the USB reset or Resume signal is received.
3. Operation is enabled only when an external clock is selected.
4. Operation is enabled only for pins set in key return mode register 00 (KRM00).
5. Maskable interrupt that is not masked
CHAPTER 12 STANDBY FUNCTION
Table 12-3. STOP Mode Operation Status
Oscillation disabled
Operation disabled
Remains in the state before the selection of STOP mode.
Operation disabled
Operation enabled
Operation disabled
Operation enabled
Operation enabled
Operation enabled
Operation enabled
User's Manual U12978EJ3V0UD

STOP Mode Operation Status

Note 1
Note 2
Note 3
Note 4
Note 5
to suppress the
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