R01UH0822EJ0100 Rev.1.00
Page 133 of 1041
Jul 31, 2019
RX13T Group
9. Clock Generation Circuit
9.2.2
System Clock Control Register 3 (SCKCR3)
Note:
Set the PRCR.PRC0 bit to 1 (write enabled) before rewriting this register.
This register cannot be rewritten while the flash memory is being programmed or erased.
CKSEL[2:0] Bits (Clock Source Select)
These bits select the source of the system clock (ICLK), peripheral module clock (PCLKB, and PCLKD), FlashIF clock
(FCLK), from low-speed on-chip oscillator (LOCO), high-speed on-chip oscillator (HOCO), the main clock oscillator,
and the PLL circuit.
Transitions to clock sources which are not in operation are prohibited.
Address(es): 0008 0026h
b15
b14
b13
b12
b11
b10
b9
b8
b7
b6
b5
b4
b3
b2
b1
b0
—
—
—
—
—
CKSEL[2:0]
—
—
—
—
—
—
—
—
Value after reset:
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit
Symbol
Bit Name
Description
R/W
b7 to b0
—
Reserved
These bits are read as 0. The write value should be 0.
R/W
b10 to b8
Clock Source Select
b10 b8
0 0 0: LOCO
0 0 1: HOCO
0 1 0: Main clock oscillator
1 0 0: PLL circuit
Settings other than above are prohibited.
R/W
b15 to b11 —
Reserved
These bits are read as 0. The write value should be 0.
R/W