Yamaha V9938 Programmer's Manual page 104

MSB 7 6
0 EC CC
1 EC CC
15 EC CC
496 EC CC
497 EC CC
511 EC CC
5.2.5. Priority mechanism and multicolored sprite combinations (SM2)
In sprite mode 2 (SM2), if the "CC" bit of the sprite color table entry is set to 1, the
sprite priority mechanism is cancelled for the specified line. Collision mechanism does not
work, mixing color codes of the lines of affected sprites using "OR" logical operation.
This logical color mixing will work for sprite N if its affected line has CC bit set, and
this line will collide with the line of another sprite which has CC bit reset to "0" and has
lower number (N-1, N-2, ..., 0 – i.e. higher priority).
Moreover, the line of the sprite having CC bit set to "1" will not be displayed at all if
there will be no lower number sprite with the line with CC bit set to "0" at the same screen
line.
Please see below for the example for the sprite combination displayed in seven colors.
© 1985 ASCII CORP. / NIPPON GAKKI CO.
5 4 3
IC 0
IC 0
IC 0
IC 0
IC 0
IC 0
2 1 0
Color code
Color code
Color code
Color code
Color code
Color code
Color code for
each line (0...15)
0: Detect
1: No detect
0: Enable
1: Disable
0: No shift
1: Shift left
Page 104 of 108
LSB
Line 1
Line 2
Colors for
sprite #0
Line 16
...
Line 1
Line 2
Colors for
sprite #31
Line 16
Line collision
detect
Sprite priority
control
Shift left 32
dots
© 2010-2015 Eugeny Brychkov
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