Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

R

15.4.1.6.OBUF_1V—Overlay Buffer 1 V Pointer Register

Memory Address Offset:

 

14h (R/W)

On-chip Reg. Mem Addr Offset:

30114h (RO; debug path)

Default Value:

 

00h

Access:

 

 

see address offset above

Size:

 

 

32 bits

31

26

25

0

 

 

 

 

Reserved

 

Overlay Buffer 1 V Pointer

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

 

 

Description

 

 

 

 

 

 

 

31:26

Reserved.

 

 

 

 

 

 

 

25:0

Overlay Buffer 1 V Pointer. This register is used for YUV Planar Modes only. It points to the start of

 

 

 

the V addresses in the interleaved UV formats (byte address).

 

 

 

 

 

 

 

15.4.2.Overlay Stride Registers

These values represent the width of the buffer that contains the overlay data. This is independent of the actual width displayed and is used to determine the line-to-line increment of the overlay buffer. In two line buffer mode, there is only room for 180 quadwords per scan line. If the source address is not quadword aligned, then for formats: YUV4:2:0, YUV4:2:2, and RGB, the source must be less then 720 pixels. The stride must be quadword aligned.

15.4.2.1.OV0STRIDE—Overlay 0 Stride Register

Memory Address Offset:

 

18h (R/W)

 

 

 

 

 

On-chip Reg. Mem Addr Offset:

30118h (RO; debug path)

 

 

 

 

Default Value:

 

00h

 

 

 

 

 

Access:

 

 

see address offset above

 

 

 

 

Size:

 

 

32 bits

 

 

 

 

 

31

26

28

16

 

15

13

12

0

 

 

 

 

Reserved

Overlay 0 UV planar

 

Reserved

 

Overlay 0 Y planar or

 

 

 

 

 

 

Buffer Stride

 

 

 

YUV/RGB Buffer Stride

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

 

 

 

 

Description

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

31:29

Reserved.

 

 

 

 

 

 

 

 

 

 

 

 

28:16

Overlay 0 UV planar Buffer Stride. Only used for YUV Planar formats and gives the U or V buffer

 

 

 

stride in bytes. This is a two’s complement number and is negative during Y mirroring. The low-order

 

 

 

three bits are always zero forcing a QWord alignment. The range is ±4 KB.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

15:13

Reserved.

 

 

 

 

 

 

 

 

 

 

 

 

12:0

Overlay 0 Y planar or YUV/RGB Buffer Stride. Buffer (Y planar or YUV/RGB packed ) stride in bytes.

 

 

 

This is a two’s complement number and is negative during Y mirroring. The low-order three bits are

 

 

 

always zero. The range is ±4 KB.

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

277

Page 277
Image 277
Intel 815 manual Overlay Stride Registers, OBUF1V-Overlay Buffer 1 V Pointer Register