HD404459 Datasheet, PDF (29/122 Pages) Renesas Technology Corp – 4-bit HMCS400-series microcomputers

HD404459 Series
Operating Modes
The MCU has five operating modes (table 19). Refer to tables 20 and 21 for the operations in each mode,
and figure 14 for the transitions between operating modes.
Active Mode: All MCU functions operate according to the clock generated by the system oscillators OSC₁
and OSC₂.
Table 19 Operating Modes and Clock Status
Mode Name
Active
Standby
Stop
Watch
Subactive*²
Activation method
RESET
SBY instruction
cancellation,
interrupt
request, STOPC
cancellation in
stop mode,
STOP/SBY
instruction in
subactive mode
(when direct
transfer is
selected)
STOP
STOP
INT₀, timer A or
instruction when instruction when wakeup interrupt
TMA3 = 0
TMA3 = 1
request from
watch mode
Status System OP
OP
Stopped
Stopped
Stopped
oscillator
Subsystem OP
OP
OP*¹
OP
OP
oscillator
Cancellation
method
RESET input,
STOP/SBY
instruction
RESET input, RESET input,
interrupt request STOPC input in
stop mode
RESET input, RESET input,
INT₀, timer A or STOP/SBY
wakeup interrupt instruction
request
Note:
OP implies in operation
1. Operating or stopping the oscillator can be selected by setting bit 3 of the system clock select
register (SSR1 : $029).
2. Subactive mode is an optional function; specify it on the function option list.
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