SH7708 Datasheet, PDF (174/625 Pages) Renesas Technology Corp – SuperH™ RISC engine

is fixed by the clock operation mode. The clock operation mode is set by pins MD0, MD1, and
MD2. See table 9.3 for more information on clock operation modes.
3. Crystal Oscillator: This oscillator is used when a crystal oscillator element is connected to the
XTAL and EXTAL pins. It operates according to the clock operating mode setting.
4. Divider 1: Divider 1 generates a clock at the operating frequency used by the internal clock. The
operating frequency can be 1, 1/2, 1/3*, or 1/4 times the output frequency of PLL circuit 1, as
long as it stays at or above the clock frequency of the CKIO pin. The division ratio is set in
the frequency control register.
Note: SH7708R only
5. Divider 2: Divider 2 generates a clock at the operating frequency used by the peripheral clock.
The operating frequencies can be 1, 1/2, 1/3*, or 1/4 times the output frequency of PLL Circuit
1 or the clock frequency of the CKIO pin, as long as it stays at or below the clock frequency of
the CKIO pin. The division ratio is set in the frequency control register.
Note: SH7708R only
6. Clock Frequency Control Circuit: The clock frequency control circuit controls the clock
frequency using the MD pin and the frequency control register.
7. Standby Control Circuit: The standby control circuit controls the status of the clock pulse
generator and other modules during clock switching and sleep/standby modes.
8. Frequency Control Register: The frequency control register has control bits assigned for the
following functions: clock output/non-output from the CKIO pin, on/off control of PLL
circuit 1, PLL standby, the frequency multiplication ratio of PLL 1, and the frequency division
ratio of the internal clock and the peripheral clock.
9. Standby Control Register: The standby control register has bits for controlling the power-down
modes. See section 8, Power-Down Modes, for more information.
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