6 CLOCK MANAGEMENT UNIT (CMU)
6-18
Seiko Epson Corporation
S1C33L26 TECHNICAL MANUAL
D[3:2]
Reserved
D1
OSC1EN: OSC1 Enable Bit
Enables or disables OSC1 oscillator operations.
1 (R/W): Enabled (on) (default)
0 (R/W): Disabled (off)
Note: Do not stop the OSC1 oscillator if the OSC1 clock is being used as the system clock.
D0
OSC3EN: OSC3 Enable Bit
Enables or disables OSC3 oscillator operations.
1 (R/W): Enabled (on) (default)
0 (R/W): Disabled (off)
Note: The OSC3 oscillator cannot be stopped if the OSC3 or PLL clock is being used as the system
clock.
LCDC Clock Division Ratio Select Register (CMU_LCLKDIV)
Register name Address
Bit
Name
Function
Setting
Init. R/W
Remarks
LCDC Clock
Division Ratio
Select Register
(CMU_
LCLKDIV)
0x300103
(8 bits)
D7–5 –
reserved
–
–
–
0 when being read.
D4–0 LCLKDIV[4:0] LCDC clock division ratio select
LCLKDIV[4:0]
Division ratio
0x7 R/W Clock source =
OSC3
Write-protected
0x1f
0x1e
0x1d
0x1c
0x1b
0x1a
0x19
0x18
0x17
0x16
0x15
0x14
0x13
0x12
0x11
0x10
0xf
0xe
0xd
0xc
0xb
0xa
0x9
0x8
0x7
0x6
0x5
0x4
0x3
0x2
0x1
0x0
1/32
1/31
1/30
1/29
1/28
1/27
1/26
1/25
1/24
1/23
1/22
1/21
1/20
1/19
1/18
1/17
1/16
1/15
1/14
1/13
1/12
1/11
1/10
1/9
1/8
1/7
1/6
1/5
1/4
1/3
1/2
1/1
D[7:5]
Reserved
D[4:0]
LCLKDIV[4:0]: LCDC Clock Division Ratio Select Bits
Selects the LCDC clock (LCLK) from among 32 kinds of OSC3 division clocks. Select a clock accord-
ing to the frame rate.
f
LCLK
Frame rate = ————— [Hz]
HT
×
VT
f
LCLK
: LCLK frequency
HT: Horizontal total period (horizontal panel size + horizontal non-display period) [pixels]
VT: Vertical total period (vertical panel size + vertical non-display period) [lines]