CHAPTER 8 STANDBY FUNCTION
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Users Manual U10676EJ3V0UM
(1) Application example of STOP mode (when using the
µ
PD754244 at fX = 6.0 MHz)
<When using the STOP mode under the following conditions>
The STOP mode is set at the falling edge of INT0 and released at the rising edge.
All the I/O ports go into a high-impedance state (if the pins are externally processed so that the current
consumption is reduced in a high-impedance state).
Interrupts INTBT and INTT0 are used in the program. However, these interrupts are not used to release the
STOP mode.
The interrupts are enabled even after the STOP mode has been released.
After the STOP mode has been released, operation is started with the slowest CPU clock.
The wait time that elapses after the mode has been released is about 21.8 ms.
A wait time of 21.8 ms elapses until the power supply stabilizes after the mode has been released. The P61/
INT0 pin is checked twice to prevent chattering.
<Timing chart>
0 V
VDD
P61/INT0
CPU operation
STOP instruction
INT0 INT0
About
21.8 ms
Operation mode STOP mode
HALT mode (wait)
Low-speed operation
High-speed operation
VDD pin voltage
About
21.8 ms