Intel 815 manual UVVPH-UV Vertical Phase Register, HORZPH-Horizontal Phase Register

Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

R

15.4.3.2.UV_VPH—UV Vertical Phase Register

Memory Address Offset:					20h (R/W)
On-chip Reg. Mem Addr Offset:					30120h (RO; debug path)
Default Value:					00h
Access:					see address offset above
Size:					32 bits
31			20	19	16	15	4	3	0
		UV Vertical Phase 1			Reserved	UV Vertical Phase 0			Reserved
		Bit				Description
	31:20		UV Vertical Phase 1. This fractional value is only used in YUV planar formats where the UV plane
			may have a different vertical initial phase from the Y data. This field is used with Buffer 1 in frame
			mode or Field 1 in field mode.
	19:16		Reserved.
	15:4		UV Vertical Phase 0. This fractional value is only used in YUV planar formats where the UV plane
			may have a different vertical initial phase from the Y data. This field is used with Buffer 0 in frame
			mode or Field 0 in field mode.
	3:0		Reserved.

15.4.3.3.HORZ_PH—Horizontal Phase Register

Memory Address Offset:					24h (R/W)
On-chip Reg. Mem Addr Offset:					30124h (RO; debug path)
Default Value:					00h
Access:					see address offset above
Size:					32 bits
31			20	19	16	15	4	3	0
		UV Horizontal Phase			Reserved	Y/RGB Horizontal			Reserved
						Phase
		Bit				Description
	31:20		UV Horizontal Phase. Sets the initial horizontal phase for the UV data. Only used in YUV modes.
	19:16		Reserved.
	15:4		Y/RGB Horizontal Phase. Sets the initial horizontal phase for both buffers/fields. Unlike the vertical
			initial phases, this does not change buffer to buffer or field to field. YUV modes use a separate initial
			phase for Y and UV data. This value will either be the actual initial phase or the initial phase minus
			one.
	3:0		Reserved.

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