M16C65 Datasheet, PDF (174/829 Pages) Renesas Technology Corp – RENESAS MCU M16C FAMILY / M16C/60

Under development
M16C/65 Group
Preliminary Specification
This is a preliminary specification and is subject to change.
9. Power Control
9.3.3 Wait Mode
In wait mode, the CPU clock, CPU, watchdog timer, and NMI/SD digital filter are turned off as they are
operated by the CPU clock. However, if the CSPRO bit in the CSPR register is 1 (count source
protection enabled), the watchdog timer remains active. Because the main clock, fOCO-F, fOCO-S, and
fC do not stop, the peripheral functions using these clocks keep operating.
9.3.3.1 Peripheral Function Clock Stop Function
When the CM02 bit is 1 (peripheral function clock f1 turned off during wait mode), the f1 clock is
turned off while in wait mode, and power consumption is reduced. However, all the peripheral clocks
except f1 (i.e. fOCO-F, fOCO-S, fC, and fC32) do not stop.
9.3.3.2 Entering Wait Mode
The MCU enters wait mode by executing a WAIT instruction.
When the CM11 bit is 1 (PLL clock selected as CPU clock source), set the CM11 bit to 0 (main clock
selected as CPU clock source) before entering wait mode. Chip power consumption can be reduced
by setting the PLC07 bit to 0 (PLL off).
9.3.3.3 Pin Status in Wait Mode
Table 9.6 lists Pin Status in Wait Mode.
Table 9.6 Pin Status in Wait Mode
Pin
A0 to A19, D0 to D15,
CS0 to CS3, BHE
RD, WR, WRL, WRH
HLDA, BCLK
ALE
I/O ports
CLKOUT
fC selected
f1, f8, f32
selected
Memory Expansion Mode
Microprocessor Mode
Retains the status just prior to
entering wait mode
High
High
Low
Retains the status just prior to
entering wait mode
Cannot be used as a CLKOUT
pin
Single-Chip Mode
Cannot be used as a bus control pin
Retains the status just prior to entering
wait mode
Does not stop
Does not stop when the CM02 bit is 0.
When the CM02 bit is 1, the status
immediately prior to entering wait
mode is maintained
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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