HD404339 Datasheet, PDF (21/80 Pages) Hitachi Semiconductor – 4-bit HMCS400-Series microcomputer with large-capacity memory

HD404339 Series
Operating Modes
The MCU has five operating modes as shown in table 3. Transitions between operating modes are shown
in figure 11.
Table 3 Operations in Each Operating Mode
Function
Subactive
Active Mode Mode
Standby Mode Watch Mode Stop Mode
System oscillator OP
Stopped
OP
Stopped
Stopped
Subsystem oscillator OP
OP
OP
OP
* OP
CPU
OP
OP
Retained
Retained
Reset
RAM
OP
OP
Retained
Retained
Retained
Timer A
OP
OP
OP
OP
Reset
Timers B, C
OP
OP
OP
Stopped
Reset
Serial
OP
OP
OP
Stopped
Reset
A/D
OP
Stopped
OP
Stopped
Reset
I/O
OP
OP
Retained
Retained
Reset
Notes: OP
implies in operation.
* Oscillation can be switched on or off with bit 3 of system clock selection register 1 (SSR1: $027).
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