Intel 815 manual 12.3.15. BR14-Destination Width & Height

Models: 815

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Intel® 815 Chipset: Graphics Controller PRM, Rev 1.0

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12.3.15. BR14—Destination Width & Height

Memory Offset Address:

40038h

Default:

None

Attributes:

RO; DWord accessible

BR14 contains the values for the height and width of the data to be BLT. If these values are not correct, such that the BLT Engine is either expecting data it does not receive or receives data it did not expect, the system can hang.

31

29

28

16

 

 

 

Reserved. Must

 

Destination Height

 

 

 

 

be Zero

 

 

 

 

 

 

 

 

 

 

 

15

13

12

0

 

 

 

Reserved. Must

 

Destination Byte Width

 

 

 

 

be Zero

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Bit

 

 

 

Descriptions

 

 

 

 

 

 

 

31:29

 

Reserved. Must be Zero.

 

 

 

 

 

 

 

28:16

 

Destination Height. These 13 bits specify the height of the destination data in terms of the number of

 

 

 

 

scan lines. This is a working register.

 

 

 

 

 

 

 

 

 

15:13

 

Reserved. Must be Zero.

 

 

 

 

 

 

 

12:0

 

Destination Byte Width. These 13 bits specify the width of the destination data in terms of the number

 

 

 

 

of bytes per scan line. The number of pixels per scan line into which this value translates depends upon

 

 

 

 

the color depth to which the graphics system has been set.

 

 

 

 

 

NOTES:

 

This is a working register. If BR14 is read while the BLT Engine is busy, the contents are unpredictable.

 

 

 

 

The value contained in this register while the BLT Engine is busy has no relationship to the programmed

 

 

 

 

value that can be read when the BLT Engine is idle.

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Page 198
Image 198
Intel 815 manual 12.3.15. BR14-Destination Width & Height