M16C65 Datasheet, PDF (141/829 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.
8. Clock Generator
CM13 (XIN-XOUT Feedback Resistor Select Bit) (b3)
The CM13 bit can be used when the main clock is not used at all, or when the externally generated
clock is supplied to the XIN pin. When connecting a resonator between pins XIN and XOUT, set the
CM13 bit to 0 (internal feedback resistor connected). Do not set this bit to 1.
When the CM10 bit is 1 (stop mode), the feedback resistor is not connected regardless of the CM13 bit
status.
CM14 (125 kHz On-Chip Oscillator Stop Bit) (b4)
The CM14 bit can be set to 1 (125 kHz on-chip oscillator off) when the CM21 bit is 0 (main clock or PLL
clock). When the CM21 bit is set to 1 (on-chip oscillator clock), the CM14 bit is automatically set to 0
(125 kHz on-chip oscillator on) and remains unchanged even when 1 is written to this bit. Note that the
125 kHz on-chip oscillator does not stop.
When the CSPRO bit in the CSPR register is 1 (watchdog timer count source protection mode), the
CM14 bit is automatically set to 0 (125 kHz on-chip oscillator on) and remains unchanged even when 1
is written to this bit. Note that the 125 kHz on-chip oscillator does not stop.
CM15 (XIN-XOUT Drive Capacity Select Bit) (b5)
When entering stop mode or the CM05 bit is set to 1 (main clock stopped) in low speed mode, the
CM15 bit is automatically set to 1 (drive capacity high).
CM17-CM16 (Main Clock Division Select Bit 1) (b7-b6)
Bits CM17 to CM16 are valid when the CM06 bit is set to 0 (bits CM16 and CM17 enabled).
REJ09B0484-0030 Rev.0.30 Sep 09, 2008
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