910GL datasheet(251/426 Pages) INTEL

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Functional Description

Datasheet

251

device, but has no native panel fitting capabilities. The GMCH will, however, provide unscaled

mode where the display is centered on the panel.

12.7.2.2.2

LVDS Capabilities

The GMCH may use the multiplexed SDVO ports to drive a LVDS transmitter. Flat Panel is a

fixed resolution display. The GMCH supports panel fitting in the transmitter, receiver or an

external device, but has no native panel fitting capabilities. The GMCH will, however, provide

unscaled mode where the display is centered on the panel. The GMCH supports scaling in the

LVDS transmitter through the SDVO stall input pair.

12.7.2.2.3

TV-Out Capabilities

Although traditional TVs are not digital displays, the GMCH uses a digital display channel to

communicate with a TV-Out transmitter. For that reason, the GMCH considers a TV-Output to be

a digital display. GMCH supports NTSC and PAL standard definition formats. The GMCH

generates the proper timing for the external encoder. The external encoder is responsible for

generation of the proper format signal. Since the multiplexed SDVO interface is a

NTSC/PAL/SECAM display on the TV-Out port , it can be configured to be the boot device. It is

necessary to ensure that appropriate BIOS support is provided. If EasyLink is supported in the

GMCH, then this mechanism could be used to interrogate the display device.

The TV-Out interface on the GMCH is addressable as a master device. This allows an external

TV encoder device to drive a pixel clock signal on SDVO_TVClk[+/-] that the GMCH uses as a

reference frequency. The frequency of this clock is dependent on the output resolution required.

Flicker Filter and Overscan Compensation

The overscan compensation scaling and the flicker filter is done in the external TV encoder chip.

Care must be taken to allow for support of TV sets with high performance de-interlacers and

progressive scan displays connected to by way of a non-interlaced signal. Timing will be

generated with pixel granularity to allow more overscan ratios to be supported.

Direct YUV from Overlay

When source material is in the YUV format and is destined for a device that can take YUV format

data in, it is desired to send the data without converting it to RGB. This avoids the truncation

errors associated with multiple color conversion steps. The common situation will be that the

overlay source data is in the YUV format and will bypass the conversion to RBG as it is sent to

the TV port directly.

Sync Lock Support

Sync lock to the TV will be done using the external encoders PLL combined with the display

phase detector mechanism. The availability of this feature will be used to determine which

external encoder is in use.

910GL датащи(PDF) 251 Page - Intel Corporation