6 CLOCK MANAGEMENT UNIT (CMU)
S1C33L26 TECHNICAL MANUAL
Seiko Epson Corporation
6-23
PLL Input Clock Division Ratio Select Register (CMU_PLLINDIV)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
PLL Input Clock
Division Ratio
Select Register
(CMU_
PLLINDIV)
0x300107
(8 bits)
D7–4 –
reserved
–
–
–
0 when being read.
D3–0 PLLINDIV
[3:0]
PLL input clock division ratio
select
PLLINDIV[3:0] Division ratio
0x7 R/W Clock source =
OSC3
Write-protected
0xf–0xa
0x9
0x8
0x7
0x6
0x5
0x4
0x3
0x2
0x1
0x0
1/8
1/10
1/9
1/8
1/7
1/6
1/5
1/4
1/3
1/2
1/1
D[7:4]
Reserved
D[3:0]
PLLINDIV[3:0]: PLL Input Clock Division Ratio Select Bits
Selects the PLL input clock (OSC3 division ratio).
10.7 PLL Input Clock (OSC3 Division Ratio) Selections
Table 6.
PLLINDIV[3:0]
Division ratio (OSC3/n)
0xf–0xa
1/8
0x9
1/10
0x8
1/9
0x7
1/8
0x6
1/7
0x5
1/6
0x4
1/5
0x3
1/4
0x2
1/3
0x1
1/2
0x0
1/1
(Default: 0x7)
Notes: • The PLL input clock can only be selected when the PLL is turned off (PLLPOWR/CMU_
PLLCTL0 register = 0) and the clock source is other than the PLL (CLKSEL[1:0]/CMU_
OSCSEL register is not 0x2). If the PLL input clock is changed while the system is operating
with the PLL clock, the system may operate erratically.
• For the range of the input clock frequency, see “Electrical Characteristics.”