HD404818 Datasheet, PDF (28/100 Pages) Hitachi Semiconductor – 16-digit LCD driver

HD404818 Series
Operating Modes
The MCU has five operating modes that are specified by how the clock is used. The functions available in
each mode are listed in table 15, and operations are shown in table 16. Transitions between operating
modes are shown in figure 9.
Table 16 provides additional information for table 26.
Table 15 Functions Available in Each Operating Mode
Mode Name
Active
Standby
Stop
Watch
Subactive*⁴
Activation method
RESET
cancellation,
interrupt
request
SBY
instruction
TMA3 = 0,
STOP
instruction
TMA3 = 1,
STOP
instruction
INT₀ or timer A
interrupt
request from
watch mode
Status System oscillator OP
OP
Stopped
Stopped
Stopped
Subsystem oscillator OP
OP
OP *¹
OP
OP
Instruction execution OP
(ø_CPU)
Peripheral function, OP
interrupt (ø_PER)
Clock function,
OP
interrupt (ø_CLK)
RAM
OP
Stopped
OP
OP
Retained
Stopped
Stopped
Stopped
Retained
Stopped
Stopped
OP *²
Retained
OP
OP
OP *²
OP
Registers/flags
OP
Retained
Reset
Retained
OP
I/O
OP
Retained
High
Retained*³ OP *³
impedance*³
Cancellation method
RESET input, RESET input, RESET input
STOP/SBY interrupt
instruction request
RESET input, RESET input,
INT₀ or timer A STOP/SBY
interrupt
instruction
request
Notes: OP indicates operating.
1. To reduce current dissipation, stop all oscillation in external circuits.
2. Refer to the Interrupt Frame section for details.
3. Refer to interrupt frame.
4. Subactive mode is an optional function to be specified on the function option list.
5. In the watch and subactive modes, the MCU requires a 32.768-kHz crystal oscillator.
26