ALXD800EEXJ2VD AMD (ADVANCED MICRO DEVICES), ALXD800EEXJ2VD Datasheet - Page 258

• Manufacturer Part Number: ALXD800EEXJ2VD
• Manufacturer: AMD (ADVANCED MICRO DEVICES)

Specifications of ALXD800EEXJ2VD

• Operating Temperature (min): 0C
• Operating Temperature (max): 85C
• Operating Temperature Classification: Commercial
• Mounting: Surface Mount
• Lead Free Status / RoHS Status: Compliant

6.4.2.3
GP Memory Offset 04h
Type
Reset Value
This register specifies the axial and diagonal error terms used by the Bresenham vector algorithm. GP_VEC_ERR shares
the same storage space as GP_SRC_OFFSET and thus a write to one of these registers will be reflected in both, since
they both have the same offset. The name change is only for documentation purposes.
6.4.2.4
GP Memory Offset 08h
Type
Reset Value
The GP_STRIDE register is used to indicate the byte width of the destination and source images. Whenever the Y coordi-
nate is incremented, this value is added to the previous start address to generate the start address for the next line. Stride
values up to 64 KB minus one are supported. Adding the GP_STRIDE to the OFFSET gives the byte address for the first
pixel of the next line of a BLT. In the case of monochrome source, the XLSBs specified in the GP_SRC_OFFSET register
are used to index into the first byte of every line to extract the first pixel.
Note that the Display Controller may not support variable strides for on-screen space, especially when compression is
enabled. Refer to DC Memory Offset 034h[15:0] for frame buffer pitch. Display Controller restrictions do not apply to source
stride.
When copying from on-screen frame buffer space (e.g., window move), the values of S_STRIDE and D_STRIDE should
match. When copying from off-screen space, S_STRIDE should be the number of bytes to add to get from one line in the
source bitmap to the next. This allows software to linearly pack a bitmap into off-screen space (e.g., for an 800x600 mono-
chrome bitmap packed linearly into off-screen space, bytes per line is 100, so S_STRIDE should be written with 100).
258
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
31:29
28:26
25:24
31:16
23:0
15:0
Bit
Bit
Vector Error (GP_VEC_ERR)
Stride (GP_STRIDE)
Name
RSVD
XLSBS
RSVD
OFFSET
Name
A_ERR
D_ERR
R/W
00000000h
R/W
00000000h
33234C
S_STRIDE
A_ERR
Description
Reserved. Write as read.
X LSBs. Offset within byte to first monochrome pixel.
Reserved. Write as read.
Offset. Offset from the source base address to the first source pixel.
Description
Axial Error Term. Axial error term (2’s complement format).
Diagonal Error Term. Diagonal error term (2’s complement format).
GP_SRC_OFFSET Bit Descriptions
GP_VEC_ERR Bit Description
GP_VEC_ERR Register Map
GP_STRIDE Register Map
Graphics Processor Register Definitions
AMD Geode™ LX Processors Data Book
9
9
D_STRIDE
D_ERR
8
8
7
7
6
6
5
5
4
4
3
3
2
2
1
1
0
0