SH7708 Datasheet, PDF (187/625 Pages) Renesas Technology Corp – SuperH™ RISC engine

Bits 13, 1 and 0—Peripheral Clock Frequency Division Ratio (PFC): These bits specify the
division ratio of the peripheral clock frequency with respect to the frequency of the output
frequency of PLL circuit 1 or the frequency of the CKIO pin.
Bit 13: PFC2 Bit 1: PFC1 Bit 0: PFC0 Description
0
0
0
×1
0
0
1
× 1/2
1
0
0
× 1/3
1
1
0
× 1/4
Note: Do not set the peripheral clock frequency higher then the frequency of the CKIO pin.
Bit 8—Clock Enable (CKOEN): Used to output a clock in operating mode 3–6 from the CKIO pin
or to fix the level of the CKIO pin in clock operation modes 3 and 4. Even when the level is fixed,
the SH7708R will operate internally at the frequency before the level was fixed. In case of clock
operating mode 0–2, set this bit to 1. In case of clock operating mode 7, the CKIO pin becomes
an input pin irrespective of the value of this bit.
Bit 8: CKOEN
0
1
Description
Fixes the level of CKIO terminal.
Outputs a clock from the CKIO pin.(Initial value)
Bit 7—PLL Circuit Enable (PLLEN): Specifies the on/off state of PLL circuit 1. This bit is valid
in clock operating modes 3 and 4. PLL circuit 1 goes on when the clock operating mode is 0–2 or
7 irrespective of the value of PLLEN.
Bit 7: PLLEN
0
1
Description
PLL circuit 1 is not used.(Initial value)
PLL circuit 1 is used.
Bit 6—PLL Standby (PSTBY): Specifies PLL standby. When PLL standby is active, PLL circuit
1 will be in standby mode at the frequency specified by the STC bit. This function is valid in
clock operating modes 3 and 4.
Bit 6: PSTBY
0
1
Description
PLL is not in standby mode. (Initial value)
PLL is in standby mode.
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