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CHAPTER 15 STANDBY FUNCTION
User’s Manual U15104EJ2V0UD
15.2.2 STOP mode
(1) STOP mode set and operating status
The STOP mode is set by executing the STOP instruction.
Cautions 1. When the STOP mode is set, the X1 pin is pulled down to GND, and the X2 pin is internally
pulled up to V
DD
to minimize the leakage current at the crystal oscillator block.
2. Because the 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 released if set. Thus, the STOP mode is reset to the HALT
mode immediately after execution of the STOP instruction. After the wait set using the
oscillation stabilization time select register (OSTS), the operation mode is set.
The operating status in the STOP mode is described below.
Table 15-3. STOP Mode Operating Status
Item
Status
Clock generator
Can oscillate system clock. Stops clock supply to CPU.
CPU
Stops operating.
Port
Holds status before HALT mode is set.
8-bit timer/event counter
Operation stops and cannot operate.
Basic timer
Watchdog timer
Buzzer output controller
A/D converter
Serial interface
(SIO30 to SIO32)
External interrupt
Can operate.
PLL frequency synthesizer
Operation stops and cannot operate.
Frequency counter
Power-on clear circuit
RESET generated when detecting 2.2 V or less.
Содержание mPD178053
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