Integrated Functions (Continued)
Table 4-31. Display Controller Memory Organization Registers (Continued)
Bit
Name
Description
GX_BASE+8318h-831Bh
DC_CUR_ST_OFFSET Register (R/W)
Reserved: Set to 0.
CUR_START Cursor Start Offset: This value represents the byte offset of the starting location of the cursor display
Default Value = xxxxxxxxh
31:22
21:0
RSVD
_OFFSET
pattern. Bits [1:0] should always be programmed to zero so that the start offset is DWORD aligned. The
cursor data will be stored as a linear block of data. The active cursor will always be 32x32x2 bits in size.
Multiple cursor patterns may be loaded into off-screen memory. The start offset is loaded at the start of a
frame. Each cursor pattern will be exactly 256 bytes in size. Note that if there is a Y offset for the cursor
pattern, the cursor start offset should be set to point to the first displayed line of the cursor pattern. The
cursor code for a given pixel is determined by an AND mask and an XOR mask. Each line of a cursor will
be stored as two DWORDs, with each DWORD containing the AND masks for 16 pixels in the upper
word and the XOR masks for 16 pixels in the lower word. DWORDs will be arranged with the leftmost
block of 16 pixels being least significant and the rightmost block being most significant. Pixels within
words will be arranged with the leftmost pixels being most significant and the rightmost pixels being least
significant. The 2-bit cursor codes are as follows.
AND
XOR
Displayed
0
0
1
1
0
1
0
1
Cursor Color 0
Cursor Color 1
Transparent − Background Pixel
Inverted − Bit-wise Inversion of Background Pixel
GX_BASE+831Ch-831Fh
GX_BASE+8320h-8323h
Reserved
Default Value = 00000000h
Default Value = xxxxxxxxh
DC_VID_ST_OFFSET Register (R/W)
Reserved: Set to 0.
31:21
20:0
RSVD
VID_START
_OFFSET
Video Buffer Start Offset Value: This is the value for the Video Buffer Start Offset. It represents the
starting location for Video Buffer. Bits [3:0] should always be programmed as zero so that the start offset
is aligned to a 16 byte boundary.
GX_BASE+8324h-8327h
DC_LINE_DELTA Register (R/W)
Reserved: Set to 0.
Default Value = xxxxxxxxh
31:22
21:12
RSVD
CB_LINE_
DELTA
Compressed Display Buffer Line Delta: This value represents number of DWORDs that, when added
to the starting offset of the previous line, will point to the start of the next compressed line in memory. It
is used to always maintain a pointer to the starting offset for the compressed display buffer line being
loaded into the display FIFO.
11:10
9:0
RSVD
Reserved: Set to 0.
FB_LINE_
DELTA
Frame Buffer Line Delta: This value represents number of DWORDs that, when added to the starting
offset of the previous line, will point to the start of the next frame buffer line in memory. It is used to
always maintain a pointer to the starting offset for the frame buffer line being loaded into the display
FIFO.
GX_BASE+8328h-832Bh
DC_BUF_SIZE Register (R/W)
Default Value = xxxxxxxxh
31:30
29:16
RSVD
Reserved: Set to 0.
VID_BUF_
SIZE
Video Buffer Size: These bits set the video buffer size, in 64-byte segments. The maximum size is 1
MB.
15:9
8:0
CB_LINE_
SIZE
Compressed Display Buffer Line Size: This value represents the number of DWORDs for a valid com-
pressed line plus 1. It is used to detect an overflow of the compressed data FIFO. It should never be
larger than 41h or 65Dh since the maximum size of the compressed data FIFO is 64 DWORDs.
FB_LINE_
SIZE
Frame Buffer Line Size: This value specifies the number of QWORDS (8-byte segments) to transfer for
each display line from the frame buffer.
If panning is enabled, this value can generally be programmed to the displayed number of QWORDS + 2
so that enough data is transferred to handle any possible alignment. Extra pixel data in the FIFO at the
end of a line will automatically be discarded.
GX_BASE+832Ch-832Fh
Reserved
Default Value = 00000000h
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