Owner's manual

Table Of Contents
DS785UM1 7-3
Copyright 2007 Cirrus Logic
Raster Engine With Analog/LCD Integrated Timing and Interface
EP93xx User’s Guide
7
7
Since the frame buffer is stored in SDRAM memory, supporting displays with high frame rates
at high resolutions will not be practical and sometimes not possible without using displays
that have an integrated frame buffer.
7.2 Features
Hardware pixel blinking
Dual 256-color Look-up-tables (LUT)
Grayscale/Color Generation for Monochrome/Passive Low Color Displays
Flexible frame buffer architecture
Supports video information in DIB (Device Independent Bitmap) format
Hardware support for left and right panning of the displayed information
Supports screen sizes up to 1280 x 1024 pixels, with a pixel depth of 4 bpp, 8 bpp, 16
bpp, 24 bpp packed, or 32 bpp (24 bpp unpacked)
Note: Using the Maximum Resolution causes system performance to slow.
Pulse Width Modulated output that can be used to provide a DC voltage level for
brightness control
Hardware cursor support with bottom and right edge clipping performed by hardware
24-bit color depth, but only 18 bits is bond-out
7.3 Raster Engine Features Overview
7.3.1 Hardware Blinking
The raster engine pipeline contains hardware pixel blinking logic. This circuitry will blink
pixels based on the Rate field in the BlinkRate register. For 4 bpp and 8 bpp modes, either
multiple or single bit planes may be used to specify blinking pixels by look up in the LUT. This
will allow the number of definable blinking pixels to range from all pixel combinations blinking
SXGA CRT 1280 x 1024 110
8, 16, or
24bpp
Analog 1 NA 70
External
DAC
HDTV-2 LCD 1280 x 720 50
8, 16, or 24
bpp
24-bit RGB 1 50 50 24-bits
HDTV-2 CRT 1280 x 720 66
8, 16, or 24
bpp
Analog 1 NA 60
External
DAC
Table 7-1. Raster Engine Video Mode Output Examples
Display
Type
Horizontal
Resolution
x
Vertical
Resolution
Video
Clock
Freq.
(MHz)
Frame
Buffer
Storage
Format
Display
Data
Format
Pixels
Per
Shift
Clock
Pixel
Shift
Clock
Freq.
(MHz)
Vertical
Frame
Rate
(Hz)
Notes