MB86290A Datasheet, PDF (131/184 Pages) Fujitsu Component Limited. – Graphics Controller Hardware Specifications

Bits 12-9
LOG (Logical operation)
Set type of logical calculation
0000 CLEAR
0001 AND
0010 AND REVERSE
0011 COPY
0100 AND INVERTED
0101 NOP
0110 XOR
0111 OR
1000 NOR
1001 EQUIV
1010 INVERT
1011 OR REVERSE
1100 COPY INVERTED
1101 OR INVERTED
1110 NAND
1111 SET
Bits 29-28
TT (Texture-Tile Select)
Select texture or tile pattern
00 Not used
01 Enable tiling operation
10 Enable texture mapping
11 Reserved
131