Corvalent Gator Mini-ITX, Руководство по установке

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Gator Mini-ITX – Installation Guide
Display Features
The Intel 855GME GMCH has four display ports, one analog and three digital. With these interfaces, the GMCH
can provide support for a progressive scan analog monitor, a dedicated dual channel LVDS LCD panel, and two
DVO devices (not available in the Gator Mini-ITX). Each port can transmit data according to one or more protocols.
The data that is sent out the display port is selected from one of the two possible sources, Pipe A or Pipe B.
GMCH Analog Display Port
Intel 855GME GMCH has an integrated 350-MHz, 24-bit RAMDAC that can directly drive a progressive scan
analog monitor pixel resolution up to 1600x1200 at 85-Hz refresh and up to 2048x1536 at 75-Hz refresh. The
Analog display port can be driven by Pipe A or Pipe B.
Analog Display Port Characteristics
The Analog display port provides an RGB signal output along with an HSYNC and VSYNC signal.
There is an associated DDC signal pair that is implemented using GPIO pins dedicated to the analog port. The
intended target device is for a CRT based monitor with a VGA connector.
Integrated RAMDAC
The display function contains a 350-MHz, integrated, 24-bit, RAM-based Digital-to-Analog Converter (RAMDAC)
that transforms up to 2048X1536 digital pixels at a maximum refresh rate of 75-Hz. Three, 8-bit DACs provide the
R, G, and B signals to the monitor.
DDC (Display Data Channel)
DDC is defined by VESA. It allows communication between the host system and display. Both configuration and
control information can be exchanged allowing plug-and-play systems to be realized.
Support for DDC 1 and 2 is implemented.
GMCH Integrated LVDS Port
The Intel 855GME GMCH have an integrated dual channel LFP Transmitter interface to support LVDS LCD panel
resolutions up to UXGA The display pipe provides panel up-scaling to fit a smaller source image onto a specific
native panel size, as well as provides panning and centering support. The LVDS port is only supported on Pipe B.
The LVDS port can only be driven by Pipe B, either independently or simultaneously with the Analog Display port.
Spread Spectrum Clocking is supported: center and down spread support of 0.5%, 1%, and 2.5% utilizing an
external SSC clock.
Dedicated LVDS Interface
The GMCH has a dedicated ANSI/TIA/EIA –644-1995 Specification compliant dual channel LFP LVDS interface
that can support TFT panel resolutions up to UXGA with a maximum pixel format of 18 bpp (with SSC supported
frequency range from 35-MHz to 112-MHz (single channel/dual channel).
The display pipe selected by the LVDS display port is programmed with the panel timing parameters that are
determined by installed panel specifications or read from an onboard EDID ROM. The programmed timing values
are then “locked” into the registers to prevent unwanted corruption of the values. From that point on, the display
modes are changed by selecting a different source size for that pipe, programming the VGA registers, or selecting a
source size and enabling the VGA. The timing signals will remain stable and active through mode changes. These
mode changes include VGA to VGA, VGA to HiRes, HiRes to VGA, and HiRes to HiRes.
The transmitter can operate in a variety of modes and supports several data formats. The serializer supports 6-bit or
8-bit color and single or dual channel operating modes. The display stream from the display pipe is sent to the
LVDS transmitter port at the dot clock frequency, which is determined by the panel timing requirements. The output
of LVDS is running at a fixed multiple of the dot clock frequency, which is determined by the mode of operation;
single or dual channel.
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