MB86290A Datasheet, PDF (127/184 Pages) Fujitsu Component Limited. – Graphics Controller Hardware Specifications

7.1.5 Draw mode Parameter Registers
When wirte to the registers, use the SetRegister command. The registers
cannot be accessed from the CPU.
MDR0 (Mode Register for miscellaneous)
Register address ^{DrawBaseAddress + 420h}
Bit #
Bit field name
R/W
Default
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0
CF
CY CX
BSV BSH
RW
RW RW
RW RW
0
00
00
00
Bits 1-0
BSH (Bitmap Scale Horizontal)
Set horizontal zoom ratio of bitmap draw
00 x1
01 x2
10 x1/2
01 Reserved
Bits 3-2
BSV (Bitmap Scale Vertical)
Set vertical zoom ratio of bitmap draw
00 x1
01 x2
10 x1/2
01 Reserved
Bit 8
CX (Clip X enable)
Sets X-coordinate clipping mode
0
Disable
1
Enable
Bit 9
CY (Clip Y enable)
Sets Y-coordinate clipping mode
0
Disable
1
Enable
Bit 15
CF (Color Format)
Sets drawing color format of current draw frame
0
Indirect color mode (8 bits/pixel)
1
Direct color mode (16 bits/pixel)
127