APPENDIX H
Mode
Logic Operation Description
9
D1 = D Destination unchanged
10 D1 = S XOR D
XOR mode
11 D1 = S OR D Transparent mode
12 D1 = NOT (S OR D)‘
13
D1 = NOT (S XOR D)
14 D1 = NOT D
15 D1 = S OR (NOT D)
16
D1 = NOT S
17 D1 = (NOT S) OR D
Reverse transparent mode
18
D1 = NOR (S AND D)
19
D1 = 1
Fill destination block
+ 038 to +039
( + $026 to +$027)
XI
This location, and the three following, are often used to hold
x and y coordinates for drawing.
+ 040 to +041
See above.
+ 042 to +043
See above.
+ 044 to +045
See above.
+ 046 to +049
PATPTR
Pointer to the current fill pattern.
Y1
X2
Y2
( + $028 to +$029)
(+ $02A to + $02B)
( + 02C to + $02D)
(+ $02E to +$031)
( + $032 to +$033)
+ 050 to +051
PATMSK
This value is ANDed with Yl, and used as an index into the
fill pattern. In most cases, the correct value will be the length
of the pattern (in lines) minus one.
+ 052 to +053 (+ 034 to + $035)
MFILL
Multiplane fill pattern flag. A zero indicates a single plane fill
330
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