HD66730 Datasheet, PDF (21/131 Pages) Hitachi Semiconductor – Dot-Matrix Liquid Crystal Display Controller/Driver Supporting Japanese Kanji, Korean Font Display

HD66730/HD66731
Timing Generator
The timing generator generates timing signals for the operation of internal circuits such as DDRAM,
FCGROM, HCGROM, CGRAM, and SEGRAM. RAM read timing for display and internal operation
timing for MPU access are generated separately to avoid interference. This prevents undesirable
interferences, such as flickering, in areas other than the display area when writing data to DDRAM, for
example.
The timing generator of HD66730 generates interface control signals CL1, CL2, M, and COMD-output of
extension drivers for a extension configuration.
Display Attribute Controller
The display attribute controller displays white/black inverse, blinking, and white/black inverse blinking for
a full size font in FCGROM according to the attribute code set in the DDRAM. Refer to Display Attribute
Designation for details.
Fonts in CGRAM and bit patterns in SEGRAM control display attributes using the upper two bits (bits 7
and 6) in each display-pattern data.
Cursor Control Circuit
The cursor control circuit is used to produce a cursor on a displayed character corresponding to the
DDRAM address set in the RAM address counter (RAR). Cursors can be chosen from three types: 12th
raster-row cursor that is displayed only on the 12th raster-row of each font; blink cursor that periodically
displays the whole font in black and white and black inverted cursor that periodically displays the font in
white and black (see Figure 9). Note that when the RAM address counter (RAR) is selecting CGRAM or
SEGRAM, a cursor would be generated at that address, however, it does not have any meaning.
Note: One display line consists of 13 raster-rows.
Smooth Scroll Control Circuit
The smooth scroll control circuit is used to perform a smooth-scroll in units of dots.
When the number of characters to be displayed is greater than that possible at one time in the liquid crystal
module, this horizontal smooth scroll can be used to display characters in an easy-to-read manner for each
line. Refer to Horizontal Smooth Scroll for details for each line.
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