W79E217A Datasheet, PDF (171/207 Pages) Winbond – 8-bit Microcontroller

Preliminary W79E217A Data Sheet
20. LCD DISPLAY
20.1 LCD Features
The LCD has the following features;
•
Selectable LCD frequency by frequency divider.
•
Two operation modes; normal (default) and Power saving mode.
•
1/3 bias voltage.
•
Two display modes; 1/3 duty or 1/4 duty
•
Segment/Com pins:
o Dedicated 10 Segment pins
o Segment 10-31 share with GPIO pins.
o Dedicated 4 com pins.
The device can directly drive a LCD with 32 segment outputs pins and 4 or 3 common output pins for
a total of 32*4 dots or 32*3 dots by direct LCD Pointer (LCDPT) and LCD Data (LCDDATA) mapping.
LCDPT can be written by (MOV LCDPT, A). If LCDEN is set, data written in the LCDDATA will
automatically display on the LCD pins. LCDDATA can be written by MOV LCDDATA, A instruction.
Figure 20-1: LCD Driver Block Diagram
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Publication Release Date: December 14, 2007
Revision A3.0