HD404618 Datasheet, PDF (31/89 Pages) Hitachi Semiconductor – 4-Bit Single-Chip Microcomputer

Interrupt
strobe
STOP/SBY
execution Internal
execution
Subactive mode
time (< T)
(LSON = 0, DTON = 1)
Direct transfer
timing
T
HD404618 Series
Oscillation
stabilization
time
Active mode
t _RC
T: Interrupt frame length
t _RC : Oscillation stabilization period
Figure 15 Direct Transfer Timing
MCU Operating Sequence: The MCU operates in the sequence shown in figures 16 to 18. It is reset by
an asynchronous RESET input, regardless of its state.
The low-power mode operation sequence is shown in figure 18. With the IE flag cleared and an interrupt
flag set together with its interrupt mask cleared, if a STOP/SBY instruction is executed, the instruction is
cancelled (regarded as an NOP) and the following instruction is executed. Before executing a STOP/SBY
instruction, make sure all interrupt flags are cleared or all interrupts are masked.
Power on
RESET = 1 ? ^No
Yes
Reset
MCU
MCU
operation
cycle
Figure 16 MCU Operating Sequence (power on)
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