hd66420 Renesas Electronics Corporation., hd66420 Datasheet - Page 27

• Manufacturer Part Number: hd66420
• Description: Ram-provided 160 Channel 4-level Grey Scale Driver For Dot Matrix Graphics Lcd
• Manufacturer: Renesas Electronics Corporation.

HD66420
Vertical Scroll Function
The HD66420 can vertically scroll a display by varying the top raster to be displayed. which is specified by
the display start raster register. Figure 15 and 16 show vertical scroll examples. As shown, when the top
raster to be displayed is set to l, data in Y address H’00_ is displayed on the 80th raster. To display another
frame on the 80th raster, therefore, data in Y address H’00_ must be modified after setting the top raster.
When display duty is less than 80, for example 1/64, data of address H’40 is displayed after address H’3F.
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