M16C65 Datasheet, PDF (168/829 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
9.3.1.4 125 kHz On-Chip Oscillator Mode
The fOCO-S clock divided by 1 (no division), 2, 4, 8 or 16 is used as the CPU clock. f1 with the same
frequency of the fOCO-S clock divided by 1 is used as the peripheral function clocks.
When fC is supplied, fC and fC32 can be used as the peripheral function clocks. fOCO-S can
be used as the peripheral function clocks. When fOCO40M and fOCO-F are supplied, they can be
used as the peripheral function clocks.
9.3.1.5 125 kHz On-Chip Oscillator Low Power Mode
The main clock and fOCO-F are turned off after the MCU enters 125 kHz on-chip oscillator mode.
The fOCO-S clock divided by 1 (no division), 2, 4, 8 or 16 is used as the CPU clock. f1 with the same
frequency of the fOCO-S clock divided by 1 is used as the peripheral function clocks.
When fC is supplied, fC and fC32 can be used as the peripheral function clocks. fOCO-S can be
used as the peripheral function clocks.
9.3.1.6 Low-Speed Mode
fC is used as the CPU clock.
When the CM21 bit is 0 and the CM11 bit is 0 (main clock), f1 with the same frequency of the main
clock divided by 1 is used as the peripheral function clocks. When the CM21 bit is 0 and the CM11 bit
is 1 (PLL clock), f1 with the same frequency of the PLL clock divided by 1 is used as the peripheral
function clocks. When the CM21 bit is 1 (on-chip oscillator clock) and the FRA01 bit is 0 (125 kHz on-
chip oscillator clock), f1 with the same frequency of the fOCO-S clock divided by 1 is used as the
peripheral function clocks. When the CM21 bit is 1 (on-chip oscillator clock) and the FRA01 bit is 1
(40 MHz on-chip oscillator clock), f1 with the same frequency of the fOCO-F clock divided by 1 is
used as the peripheral function clocks.
fC and fC32 can be used as the peripheral function clocks. When fOCO-S is supplied, it can
be used as the peripheral function clocks. When fOCO40M and fOCO-F are supplied, they can be
used as the peripheral function clocks.
9.3.1.7 Low Power Mode
The main clock and fOCO-F are turned off after the MCU enters low speed mode. fC is used as the
CPU clock. When the CM21 bit is 1 (on-chip oscillator clock) and the FRA01 bit is 0 (125 kHz on-chip
oscillator clock), f1 with the same frequency of the fOCO-S clock divided by 1 is used as the
peripheral function clocks.
fC and fC32 can be used as the peripheral function clocks. When fOCO-S is supplied, it can be used
as the peripheral function clocks.
When this mode is selected, the CM06 bit in the CM0 register simultaneously becomes 1 (divide- by-
8 mode). In low power mode, do not change the CM06 bit. Consequently, select the divide-by-8
mode when any clock (except the sub clock) is used for the next operation.
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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