Yamaha V9938 Programmer's Manual page 82

Step 2: Select destination memory and direction from base coordinate
MSB
R#45
Step 3: Define logical operation and execute the command
MSB
R#46
Step 4: Check for command completion
CPU should check CE bit of status register S#2 to identify if VDP has completed
execution of the command. When command is being executed, CE bit is set to 1; when
command is complete, CE bit will be reset to 0.
© 1985 ASCII CORP. / NIPPON GAKKI CO.
7 6 5
0 - MXD MSX
7 6 5
1 0 0
4 3 2
DIY DIX
4 3 2
1 LO3 LO2 LO1
Logical operation
Page 82 of 108
1 0 LSB
- -
0: Right X transfer
direction
1: Left
0: Down Y transfer
direction
1: Up
0: VRAM Source
location select
1: ExpRAM
0: VRAM Destination
location select
1: ExpRAM
1 0 LSB
LO0 LMMM cmd
© 2010-2015 Eugeny Brychkov