6 CLOCK MANAGEMENT UNIT (CMU)
6-22
Seiko Epson Corporation
S1C33L26 TECHNICAL MANUAL
10.5 System Clock Division Ratio
Table 6.
SYSCLKDIV[2:0]
Division ratio (OSC/n)
0x7–0x6
1/1
0x5
1/32
0x4
1/16
0x3
1/8
0x2
1/4
0x1
1/2
0x0
1/1
(Default: 0x0)
CMU_CLK Select Register (CMU_CMUCLK)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
CMU_CLK
Select Register
(CMU_CMUCLK)
0x300106
(8 bits)
D7–5 –
reserved
–
–
–
0 when being read.
D4–0 CMU_
CLKSEL[4:0]
CMU_CLK select
CMU_CLKSEL[4:0]
CMU_CLK
0x0 R/W OSC: system clock
(OSC3, PLL, OSC1)
Write-protected
0xf–0xb
0xa
0x9
0x8
0x7
0x6
0x5
0x4
0x3
0x2
0x1
0x0
reserved
OSC/32
OSC/16
OSC/8
OSC/4
OSC/2
OSC/1
LCLK
BCLK
PLL
OSC1
OSC3
D[7:5]
Reserved
D[4:0]
CMU_CLKSEL[4:0]: CMU_CLK Select Bits
Selects an internally generated clock to be output from the CMU_CLK pin to external devices.
10.6 CMU_CLK Selections
Table 6.
CMU_CLKSEL[4:0]
CMU_CLK
0xf–0xb
Reserved
0xa
OSC/32
0x9
OSC/16
0x8
OSC/8
0x7
OSC/4
0x6
OSC/2
0x5
OSC/1
0x4
LCLK
0x3
BCLK
0x2
PLL
0x1
OSC1
0x0
OSC3
(Default: 0x0)
CMU_CLK can be selected at any time. However, switching over the clocks creates hazards.
Note: Settings other than those listed in Table 6.10.6 are reserved for testing. Do not set unde-
scribed values to CMU_CLKSEL[4:0] as undesired clocks may output.