E202075_HD404889 Datasheet, PDF (142/202 Pages) Renesas Technology Corp – Low-Voltage AS Microcomputers with On-Chip LCD Circuit

HD404889/HD404899/HD404878/HD404868 Series
LCD control register (LCR: $02C):
The LCD control register is a 4-bit write-only register that controls LCD blanking, the on/off state of the
LCD power switch, display in watch mode and subactive mode, and disconnection of the LCD power
supply dividing resistor, as shown in figure 88.
Individual bit in this register can be set and reset by bit manipulation instructions.
• Display on/off control
Off: Segment signals are in the off state, regardless of LCD RAM data.
On: LCD RAM data is output as segment signals.
• Built-in power switch on/off control
Off: The built-in LCD power switch is off.
On: The built-in LCD power switch is on. If V0 and V1 are shorted externally, V1 goes to the V_CC
level.
• LCD display in watch mode and subactive mode
Off: In watch mode and subactive mode, all common and segment pins are fixed at GND potential.
The built-in LCD power switch is off.
On: In watch mode and subactive mode, LCD RAM data is output as segment signals.
• LCD power supply dividing resistor switch on/off control
Off: The built-in LCD power supply dividing resistor is disconnected.
On: The built-in LCD power supply dividing resistor is connected.
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