Specifications

44 EPSON S1C6P466 TECHNICAL MANUAL

CHAPTER 4: PERIPHERAL CIRCUITS AND OPERATION (LCD Driver)

4.7.4 LCD display control (ON/OFF) and switching of duty

(1) Display ON/OFF control

The S1C6P466 incorporates the ALON and ALOFF registers to blink display. When "1" is written to

ALON, all the dots go ON, and when "1" is written to ALOFF, all the dots go OFF. At such a time, an

ON waveform or an OFF waveform is output from SEG terminals. When "0" is written to these

registers, normal display is performed. Furthermore, when "1" is written to both of the ALON and

ALOFF, ALON (all ON) has priority over the ALOFF (all OFF).

(2) Switching of drive duty

In the S1C6P466, the drive duty can be set to 1/17, 1/16 or 1/8 by the software. This setting is done

using the LDUTY1 and LDUTY0 registers as shown in Table 4.7.4.1.

Table 4.7.4.1 LCD drive duty setting

LDUTY1

LDUTY0

∗

Drive duty

1/8

1/16

1/17

Common terminal used

COM0–COM7

COM0–COM15

COM0–COM16

Maximum segment number

480 (60 × 8)

960 (60 × 16)

1,020 (60 × 17)

Table 4.7.4.2 shows the frame frequencies corresponding to the OSC1 oscillation frequency and drive

duty.

Table 4.7.4.2 Frame frequency

OSC1 oscillation

frequency

32.768 kHz

When 1/8 duty

is selected

32 Hz

When 1/16 duty

is selected

32 Hz

When 1/17 duty

is selected

30.12 Hz

Figures 4.7.4.1 shows the dynamic drive waveform for 1/4 bias.