MiTAC 8050D manual 83

Analog CRT Display Signal Descriptions

DVOBC Interrupt: This pin is used to signal an interrupt, typically used to indicate a hot plug or unplug of a digital display. ADDID[7:0]: These pins are used to communicate to the Video BIOS when an external device is interfaced to the DVO port.

Note: Bit[7] needs to be strapped low when an on-board DVO device is present.

The other pins should be left as NC.

DVODETECT: This strapping signal indicates to the GMCH whether a DVO device is present or not. When a DVO device is connected, then DVODETECT = 0.

8050D N/B Maintenance

5.2 Intel 855GM/GME North Bridge(8)

DVOB and DVOC Port Common Signal Descriptions			Digital Video Output C (DVOC) Port Signal Descriptions
Name	Type	Description	Name	Type	Description
DVOBCINTR#	I		DVOCD[11:0]	O	DVOC Data: This data bus is used to drive 12-bit RGB data on each
	DVO			DVO	edge of the differential clock signals, DVOCCLK and DVOCCLK#.
ADDID[7:0]	I				This provides 24-bits of data per clock period. In dual channel mode,
	DVO				this provides the upper 12-bits of pixel data.
					DVOCD[11:0] should be left as left as NC (“Not Connected”) if not
					used.

DVODETECT I DVO

Pin Name	Type
VSYNC	O
	CMOS
HSYNC	O
	CMOS
RED	O
	Analog
RED#	O
	Analog
GREEN	O
	Analog
GREEN#	O
	Analog
BLUE	O
	Analog
BLUE#	O
	Analog

		DVOCHSYNC	O	Horizontal Sync: HSYNC signal for the DVOC interface.
			DVO	DVOCHSYNC should be left as left as NC (“Not Connected”) if not
				used.
		DVOCVSYNC	O	Vertical Sync: VSYNC signal for the DVOC interface.
			DVO	DVOCVSYNC should be left as left as NC (“Not Connected”) if the
				signal is NOT used when using internal graphics device.
		DVOCBLANK#	O	Flicker Blank or Border Period Indication: DVOCBLANK# is a
	Secret		DVO	programmable output pin driven by the GMCH.
				When programmed as a blank period indication, this pin indicates
				active pixels excluding the border. When programmed as a border
Description				period indication, this pin indicates active pixel including the border
CRT Vertical Synchronization: This signal is used as the vertic	l			pixels.
				DVOCBLANK# should be left as left as NC (“Not Connected”) if not
sync signal.		Documentused.
CRT Horizontal Synchronization: This signal is used as the		DVOCFLDSTL	I	TV Field and Flat Panel Stall Signal. This input can be
horizontal sync signal.
			DVO	programmed to be either a TV Field input from the TV encoder or
Red (Analog Video Output): This signal isMiTacCRT Analog video
				Stall input from the flat panel.
output from the internal color palette DAC. The DAC is desig ed for				DVOC TV Field Signal: When used as a Field input, it synchronizes
a 37.5-§Ù equivalent load each pin (e.g., 75-§Ù r sistor on the
				the overlay field with the TV encoder field when the overlay is
board, in parallel with the 75-§Ù CRT load).
				displaying an interleaved source.
Red# (Analog Output): Tied to ground.
				DVOC Flat Panel Stall Signal: When used as the Stall input, it
Green (Analog Video Output): This sig al is a CRT analog video				indicates that the pixel pipeline should stall one horizontal line. The
				signal changes during horizontal blanking. The panel fitting logic,
output from the internal color palette DAC. The DAC is designed for				when expanding the image vertically, uses this.
a 37.5-§Ù equivalent load on each pin (e.g.,75-§Ù resistor on the				DVOCFLDSTL needs to be pulled down if not used.
board, in parallel with the 75- §Ù CRT load).

Green# (Analog Output):ConfidentialTied to ground.

Blue (Analog Video Output) : This signal is a CRT Analog video output from the internal color palette DAC. The DAC is designed for a 37.5-§Ù equivalent load on each pin (e.g., 75-

ohm resistor on the board, in parallel with the 75-§Ù CRT load). Blue# (Analog Output): Tied to ground.

82