M16C65 Datasheet, PDF (183/829 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
9.4.2.2 Low Current Consumption Read Mode
Low current consumption read mode can be used when the CM07 bit in the CM0 register is 1 (sub
clock used as CPU clock). Figure 9.4 shows Setting and Canceling of Low Current Consumption
Read Mode.
Low current consumption read mode
Set the CM07 bit to 1 (sub-clock used as a CPU clock) ⁽¹⁾
Set the CM05 bit to 1 (main clock oscillation stop)
and the FRA00 bit to 0 (40 MHz on-chip oscillator stopped).
Set the FMR22 bit to 0, and then to 1 (enabled).
Setting
Procedure
Set the FMR23 bit to 0, and then to 1 (enabled).
Processing in low current consumption read mode
Set the FMR23 bit to 0 ⁽¹⁾
Set the FMR22 bit to 0 ⁽¹⁾
Canceling
Procedure
Restore the CPU clock
Completed
Note:
1. Do not rewrite bits FMR22 and FMR23 simultaneously.
Figure 9.4 Setting and Canceling of Low Current Consumption Read Mode
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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