HD404339 Datasheet, PDF (25/80 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer with large-capacity memory

HD404339 Series
STOP/SBY instruction execution
Subactive mode
MCU internal
processing period
(Set LSON = 0, DTON = 1)
Oscillation
stabilization
time
Interrupt strobe
Direct transfer
completion timing
T
t _RC
Active mode
T: Interrupt frame period
t _RC : Oscillation stabilization time
Figure 15 Direct Transition Timing
MCU Operation Sequence: The MCU operation flow is shown in figures 16 and 17. RESET input is
asynchronous, and causes an immediate transition to the reset state from any MPU operation state.
The low-power mode operation sequence is shown in figure 17. 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.
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