Cirrus Logic EP93xx - Manual (Page 189)

DS785UM1 7-7
Copyright 2007 Cirrus Logic
Raster Engine With Analog/LCD Integrated Timing and Interface
EP93xx User’s Guide
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brightness control. The Bright output signal can also be used for direct pulse width modulated
CCFL brightness control that can be synchronized to the display frame rate.
7.3.7 Hardware Cursor
The Raster Engine provides hardware cursor support. The cursor size is programmable up to
64 pixels wide by 64 pixels in height. The cursor is stored anywhere in memory as a 2 bpp
image. The 2 bpp image pixel information implies transparent, inverted, cursor color 1, or
cursor color 2. The cursor hardware must be supplied this information:
• Image starting address
• Two cursor colors
• An X screen location and a Y screen location
• A cursor size
Using this information, the hardware overlays the cursor in the output video stream. Bottom
and right edge clipping is performed by hardware. Some extra calculations and register
setups are required for cursor support during dual scan display mode.
7.4 Functional Details
The Raster Engine’s block diagram is shown in Figure 7-1 . The video pipeline consists of
several major sections; VILOSATI, video FIFO, pixel mux, blink logic, color LUT, RGB mux,
output shift logic, grayscale circuitry, hardware cursor logic, YCrCb encoder, and video timing
section. A video stream signature generator is also included for built in self testing.