P.87
operations , and as the value of the maximum term of the caculated equation for the Line Drawong
operation. In BILBLK operations, these bits define the X direction width using byte as unit . The
caculated equation of the maximum term (M) is :
M = Max ( |X
2
-X
1
| , |Y
2
-Y
1
| )
Bit 11-15
Reserved .
GAREG Hex 08 : Y Width & Error Term Register
This is a read/write register.
Default value after hardware reset is Hex 00,00.
Default port address 23C4.
PCI port address low 20.
D0-10
D0-12
D13-15
Width Y bit 0-10 for BITBLT (number of line-1)
Error term for Line drawing (E)
Reserved
Bit 0-10/12
These bits would use to define the Y direction width of the rectangular region to be copied for BITBLT
operations , and as the value of the error term of the caculated equation for the Line Drawong opera-
tion. In BILBLK operations, these bits define the Y direction width using line as unit . The caculated
equation of the error term (E) is :
E = 2 [ Min ( |X
2
-X
1
| , |Y
2
-Y
1
| )-Max ( |X
2
-X
1
| , |Y
2
-Y
1
| ) ]
Bit 13-15
Reserved .
GAREG Hex 09 : Foreground Color Register 1
This is a read/write register.
Default value after hardware reset is Hex 00,00.
Default port address 27C4.
PCI port address low 24.
D0-15
Foreground color bit 0 to 15
Bit 0-15
These bits would use to define the foreground color for rectangular fill, color expansion, and line
drawing. Conjunction with foreground color bit 16 to 31,that descripts in GAREG 0A, we must write
with the same color data(byte) into bit 0-7, bit 8-15, bit 16-23, and bit 24-31 for 256-color mode. In
different we must write with the same color data(word) into bit 0-15, and bit 16-31 for hi-color mode.
Another condiction we use bit 0-23 as color data and reserved bit 24-31 for ture-color
mode.
GAREG Hex 0A : Foreground Color Register 2
This is a read/write register.
Default value after hardware reset is Hex 00,00.
Default port address 2BC4.
PCI port address low 28.
D0-15
Foreground color bit 16 to 31
Bit 0-15
These bits would use to define the foreground color for rectangular fill, color
expansion, and line drawing.
GAREG Hex 0B : Background Color Register 1
This is a read/write register.
Default value after hardware reset is Hex 00,00.
Default port address 2FC4.
PCI port address low 2C.
D0-15
Background color bit 0 to 15