EM78468
8-BIT Microcontroller
4.1.10 R9/LCDCR (LCD Control Register)
(Address: 09h)
Bit 7
BS
Bit 6
Bit 5
DS0
Bit 4
LCDEN
Bit 3
--
Bit 2
Bit 1
Bit 0
LCDF0
DS1
LCDTYPE LCDF1
Bit 7 (BS): LCD bias select bit,
BS = “0”: 1/2 bias
BS = “1”: 1/3 bias
Bit 6 ~ 5 (DS1 ~ DS0): LCD duty select
DS1
DS0
LCD duty
0
0
1
0
1
X
1/2 duty
1/3 duty
1/4 duty
Bit 4 (LCDEN): LCD enable bit.
LCDEN = “0”: LCD circuit disable, all common/segment outputs are set to ground
(GND) level.
LCDEN = “1”: LCD circuit enable
Bit 3: Not used
Bit 2 (LCDTYPE): LCD drive waveform type select bit
LCDTYPE = “0”: A type waveform
LCDTYPE = “1”: B type waveform
Bit 1 ~ 0 (LCDF1 ~ LCDF0): LCD frame frequency control bits
LCD frame frequency (e.g. Fs=32.768KHz)
LCDF1
LCDF0
1/2 duty
1/3 duty
1/4 duty
0
0
1
1
0
1
0
1
Fs/(256*2)=64.0
Fs/(280*2)=58.5
Fs/(304*2)=53.9
Fs/(232*2)=70.6
Fs/(172*3)=63.5
Fs/(188*3)=58.0
Fs/(204*3)=53.5
Fs/(156*3)=70.0
Fs/(128*4) =64.0
Fs/(140*4) =58.5
Fs/(152*4) =53.9
Fs/(116*4) =70.6
Fs: sub-oscillator frequency
4.1.11 RA/LCD_ADDR (LCD Address)
(Address: 0Ah)
Bit 7
Bit 6
Bit 5
Bit 4
Bit 3
Bit 2
Bit 1
Bit 0
0
0
0
LCD_A4 LCD_A3 LCD_A2 LCD_A1 LCD_A0
Bit 7 ~ 5: Not used, fixed to “0”
14 •
Product Specification (V1.1) 04.11.2005
(This specification is subject to change without further notice)
ELAN [ ELAN MICROELECTRONICS CORP ]
