Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

R

12.3.5.BR04—Clip Rectangle X1 and X2

Memory Offset Address:

40010h

Default:

None

Attributes:

RO; DWord accessible

BR04 is loaded by either the SETUP_BLT or SETUP_MONO_PATTERN_SL_BLT instructions and is used with PIXEL_BLT, SCANLINE_BLT, or TEXT_BLT instructions.

 

31

28

27

16

 

 

Reserved. Must be Zero

 

Clip Rectangle X2 coordinate (right) [11:00]

 

 

 

 

 

 

 

 

15

12

11

0

 

 

Reserved. Must be Zero

 

Clip Rectangle X1 coordinate (left) [11:00]

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

 

 

Descriptions

 

 

 

 

 

 

31:28

Reserved. Must be Zero.

 

 

 

 

 

 

27:16

Clip Rectangle X2 Coordinate. These 12 bits specify the right most X coordinate which is written to

 

 

the destination. The comparison is inclusive with a less than or equal. The byte address of this

 

 

coordinate is:

 

 

 

 

 

scan line address + X2 * bytes/pixel.

 

 

 

 

 

 

15:12

Reserved. Must be Zero.

 

 

 

 

 

 

11:0

Clip Rectangle X1 Coordinate. These 12 bits specify the left most X coordinate which is written to

 

 

the destination. The comparison is inclusive with a greater than or equal. The byte address of this

 

 

coordinate is:

 

 

 

 

 

scan line address + X1 * bytes/pixel.

 

 

 

 

 

 

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Intel 815 manual 12.3.5. BR04-Clip Rectangle X1, Reserved. Must be Zero 2716