MB86290A Datasheet, PDF (120/184 Pages) Fujitsu Component Limited. – Graphics Controller Hardware Specifications

When performing blend processing, specify the blend mode for this bit; alpha
must be enabled previously in C-layer display data. In the direct color mode,
specify alpha for the most significant bit. In the indirect color mode, specify
alpha for the most significant bit of pallet data.
KEYC (Key Color)
Register address ^{DisplayBaseAddress + B8h}
Bit #
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit field name KYEN
KYC
R/W
RW
RW
Default
0
Don’t care
Bits 14-0 KYC (Key Color)
Set key color for chroma-key operation. Bits 7-0 used in indirect color mode. Bits 7-0 are used when
the indirect color mode (8 bits/pixel) and the chroma key mode are set to the C-layer color.
Bit 15
KYEN (chroma-Key Enable)
Enables/disables chroma-key operation
0
Disable chroma-key operation (H always output from GV pin).
1
Enable chroma-key operation.
CKM (Chroma Key Mode)
Register address ^{DisplayBaseAddress + BAh}
Bit #
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
Bit field name
Reserved
KCS
R/W
R0
RW
Default
0
0
Bit 0
KCS (Key Color Select)
Selects key color as C-layer color or display color
0
Set key color as display color.
1
Set key color as C-layer color.
(See Sect i on 5.5.)
120