HD404328 Datasheet, PDF (37/96 Pages) Hitachi Semiconductor – 4 BIT SINGLE CHIP MICROCOMPUTER

Low-power mode
operation cycle
HD404328 Series
No
IF = 1, IM = 0?
Yes
Hardware NOP
execution
Standby/watch mode
Stop mode
For IF and IM operation,
refer to figure 11.
IF = 1, IM = 0?
No
Yes
Hardware NOP
execution
PC ←next location
PC ←next location
Instruction execution
MCU operation
cycle
Figure 18 MCU Operating Sequence (Low-Power Mode Operation)
Limitation on Use
• In subactive mode, the timer A interrupt request or the external interrupt request (INT₀) occurs in
synchronism with the interrupt strobe. If the STOP or SBY instruction is executed at the same time
with the interrupt strobe, these interrupt requests will be cancelled and its corresponding interrupt
request flags (IFTA, IF0) will be not set.
In subactive mode, do not use the STOP or SBY instruction at the time of the interrupt strobe.
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