-
Notifications
You must be signed in to change notification settings - Fork 1
/
koalatro.asm
1048 lines (892 loc) · 15.3 KB
/
koalatro.asm
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
;
; KOALATRO
;
; Code and graphics by T.M.R/Cosine
; Music by aNdy/Cosine
; A somewhat masochistic exercise in cramming a bitmap, music,
; scroller (with unrolled colour splitting code) and text into just
; 15K of bank 0 (using space between $0400 and $3FFF) after a
; discussion on Facebook. *Strictly* speaking it's not a Koala
; format picture because some of the colour has been packed, but
; all the data is still present!
; This source code is formatted for the ACME cross assembler from
; http://sourceforge.net/projects/acme-crossass/
; Compression is handled with PuCrunch which can be downloaded at
; http://csdb.dk/release/?id=6089
; build.bat will call both to create an assembled file and then the
; crunched release version.
; Select an output filename
!to "koalatro.prg",cbm
; Yank in binary data
* = $1400
music !binary"data/lesewch_tap.prg",,$0c
; Partially packed colour data
* = $0400
!binary "data/hussein.kla",,$01f42
; Bitmap data
* = $2000
!binary "data/hussein.kla",$1f40,$02
; Constants
rstr1p = $19
rstr2p = $f2
; Static colours for the scroller
split1_col_00 = $06
split1_col_01 = $04
split1_col_02 = $0e
split1_col_03 = $0d
split1_col_04 = $03
split1_col_05 = $05
split1_col_06 = $08
split1_col_07 = $02
split1_col_08 = $09
split2_col_00 = $09
split2_col_01 = $08
split2_col_02 = $0a
split2_col_03 = $07
split2_col_04 = $0f
split2_col_05 = $0c
split2_col_06 = $04
split2_col_07 = $0b
split2_col_08 = $06
; Label assignments
rn = $50
d021_colour = $51
scroll_cnt = $52
pulse_tmr_1 = $53
pulse_tmr_2 = $54
char_buffer = $55 ; $30 bytes
sprite_buffer = $0800
; Entry point at $c000 (gets overwritten by picture data later)
* = $0a00
entry sei
; Turn off the ROMS and screen
lda #$35
sta $01
lda #$0b
sta $d011
lda #$00
sta $d020
sta $d021
sta $3fff
; Initialise $D800 colour for the picture (one byte contains two
; nybbles of colour)
lda $09dc
sta d021_colour
ldx #$00
ldy #$00
bitmap_colour lda $07e8+$000,x
sta $d800,y
lsr
lsr
lsr
lsr
sta $d801,y
lda $07e8+$080,x
sta $d900,y
lsr
lsr
lsr
lsr
sta $d901,y
lda $07e8+$100,x
sta $da00,y
lsr
lsr
lsr
lsr
sta $da01,y
cpy #$e8
bcs bitmap_skip
lda $07e8+$180,x
sta $db00,y
lsr
lsr
lsr
lsr
sta $db01,y
bitmap_skip inx
iny
iny
bne bitmap_colour
; Set up the NMI and IRQ interrupts
lda #<nmi
sta $fffa
lda #>nmi
sta $fffb
lda #<int
sta $fffe
lda #>int
sta $ffff
lda #$7f
sta $dc0d
sta $dd0d
lda $dc0d
lda $dd0d
lda #rstr1p
sta $d012
lda #$0b
sta $d011
lda #$01
sta $d019
sta $d01a
; Zero the workspaces in ZP and initialise a few labels
ldx #$53
lda #$00
nuke_zp sta $00,x
inx
bne nuke_zp
lda #$01
sta rn
lda #$b0
sta scroll_cnt
lda #$20
sta pulse_tmr_1
lda #$2b
sta pulse_tmr_2
; Since the hardware sprites don't move in X or change data pointer,
; turn them on and set both up
lda #$ff
sta $d015
sta $d01d
ldx #$00
ldy #$00
set_sprx_1 lda sprite_x,x
sta $d000,y
lda sprite_dp,x
sta $07f8,x
iny
iny
inx
cpx #$08
bne set_sprx_1
lda sprite_x+$08
sta $d010
; Clear the sprite buffer ready for use!
ldx #$00
txa
sprite_clr sta sprite_buffer+$000,x
sta sprite_buffer+$100,x
inx
bne sprite_clr
; Initialise the music
lda #$00
jsr music+$00
cli
; Runtime loop - check for space bar and quit
main_loop lda $dc01
cmp #$ef
bne main_loop
; Switch everything to black, kill the volume and reset the C64
sei
lda #$0b
sta $d011
lda #$00
sta $d020
sta $d021
sta $d418
lda #$36
sta $01
jmp $fce2
; IRQ interrupt
int pha
txa
pha
tya
pha
lda $d019
and #$01
sta $d019
bne ya
jmp ea31
ya lda rn
cmp #$02
bne *+$05
jmp rout2
; Raster split 1
rout1 lda #$3b
sta $d011
lda #$18
sta $d016
sta $d018
; Set the sprite Y positions for the upper scroller
lda #$20
sta $d001
sta $d003
sta $d005
sta $d007
sta $d009
sta $d00b
sta $d00d
sta $d00f
; Jitter removal for the upper scroller
ldx #$04
dex
bne *-$01
nop
nop
nop
nop
lda $d012
cmp #rstr1p+$01
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
nop
lda $d012
cmp #rstr1p+$02
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
nop
nop
lda $d012
cmp #rstr1p+$03
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
bit $ea
lda $d012
cmp #rstr1p+$04
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
bit $ea
lda $d012
cmp #rstr1p+$05
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
bit $ea
lda $d012
cmp #rstr1p+$06
beq *+$02
; sta $d020
nop
nop
nop
nop
nop
; Call the splitter code
jsr splitter
; Set the screen colour for the picture
ldx #$04
dex
bne *-$01
nop
nop
nop
lda d021_colour
sta $d021
; Play the music (first pass)
jsr music+$03
; Update the scroller
ldx #$00
mover asl char_buffer,x
rol sprite_buffer+$1c5,x
rol sprite_buffer+$1c4,x
rol sprite_buffer+$1c3,x
rol sprite_buffer+$185,x
rol sprite_buffer+$184,x
rol sprite_buffer+$183,x
rol sprite_buffer+$145,x
rol sprite_buffer+$144,x
rol sprite_buffer+$143,x
rol sprite_buffer+$105,x
rol sprite_buffer+$104,x
rol sprite_buffer+$103,x
rol sprite_buffer+$0c5,x
rol sprite_buffer+$0c4,x
rol sprite_buffer+$0c3,x
rol sprite_buffer+$085,x
rol sprite_buffer+$084,x
rol sprite_buffer+$083,x
rol sprite_buffer+$045,x
rol sprite_buffer+$044,x
rol sprite_buffer+$043,x
rol sprite_buffer+$005,x
rol sprite_buffer+$004,x
rol sprite_buffer+$003,x
txa
clc
adc #$06
tax
cpx #$30
beq *+$05
jmp mover
; Fetch a new character if needed
ldx scroll_cnt
dex
cpx #$ff
bne scroll_xb
mread lda scroll_text
bne okay
jsr reset
jmp mread
okay sta def_copy+$01
lda #$00
asl def_copy+$01
rol
asl def_copy+$01
rol
asl def_copy+$01
rol
clc
adc #$d8
sta def_copy+$02
lda #$33
sta $01
ldx #$00
ldy #$00
def_copy lda $6464,x
sta char_buffer,y
tya
clc
adc #$06
tay
inx
cpx #$08
bne def_copy
lda #$35
sta $01
inc mread+$01
bne *+$05
inc mread+$02
ldx #$07
scroll_xb stx scroll_cnt
; Update the reversed scroller
ldx #$00
mover_2 lda sprite_buffer+$1c5,x
lsr
ror sprite_buffer+$006,x
ror sprite_buffer+$007,x
ror sprite_buffer+$008,x
ror sprite_buffer+$046,x
ror sprite_buffer+$047,x
ror sprite_buffer+$048,x
ror sprite_buffer+$086,x
ror sprite_buffer+$087,x
ror sprite_buffer+$088,x
ror sprite_buffer+$0c6,x
ror sprite_buffer+$0c7,x
ror sprite_buffer+$0c8,x
ror sprite_buffer+$106,x
ror sprite_buffer+$107,x
ror sprite_buffer+$108,x
ror sprite_buffer+$146,x
ror sprite_buffer+$147,x
ror sprite_buffer+$148,x
ror sprite_buffer+$186,x
ror sprite_buffer+$187,x
ror sprite_buffer+$188,x
ror sprite_buffer+$1c6,x
ror sprite_buffer+$1c7,x
ror sprite_buffer+$1c8,x
txa
clc
adc #$06
tax
cpx #$30
beq *+$05
jmp mover_2
; Update the left hand half of the lower scroller's colour effect
lda pulse_tmr_1
clc
adc #$01
cmp #$5f
bcc *+$04
lda #$00
sta pulse_tmr_1
lsr
cmp #$10
bcc *+$04
lda #$00
tax
lda colour_pulse_1+$00,x
sta split_1_11+$01
lda colour_pulse_1+$01,x
sta split_1_0f+$01
lda colour_pulse_1+$02,x
sta split_1_0d+$01
lda colour_pulse_1+$03,x
sta split_1_0b+$01
lda colour_pulse_1+$04,x
sta split_1_09+$01
lda colour_pulse_1+$05,x
sta split_1_07+$01
lda colour_pulse_1+$06,x
sta split_1_05+$01
lda colour_pulse_1+$07,x
sta split_1_03+$01
lda colour_pulse_1+$08,x
sta split_1_01+$01
; Update the right hand half of the lower scroller's colour effect
lda pulse_tmr_2
clc
adc #$01
cmp #$5f
bcc *+$04
lda #$00
sta pulse_tmr_2
lsr
cmp #$10
bcc *+$04
lda #$00
tax
lda colour_pulse_2+$08,x
sta split_2_11+$01
lda colour_pulse_2+$07,x
sta split_2_0f+$01
lda colour_pulse_2+$06,x
sta split_2_0d+$01
lda colour_pulse_2+$05,x
sta split_2_0b+$01
lda colour_pulse_2+$04,x
sta split_2_09+$01
lda colour_pulse_2+$03,x
sta split_2_07+$01
lda colour_pulse_2+$02,x
sta split_2_05+$01
lda colour_pulse_2+$01,x
sta split_2_03+$01
lda colour_pulse_2+$00,x
sta split_2_01+$01
; Wait for rasterline $cb before calling the music again
lda #$cb
cmp $d012
bne *-$03
jsr music+$03
; Set up for the second raster split
lda #$02
sta rn
lda #rstr2p
sta $d012
jmp ea31
; Raster split 2
rout2 ldx #$06
dex
bne *-$01
nop
; Jitter removal for the lower scroller
lda $d012
cmp #rstr2p+$01
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
nop
lda $d012
cmp #rstr2p+$02
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
nop
nop
lda $d012
cmp #rstr2p+$03
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
nop
lda $d012
cmp #rstr2p+$04
beq *+$02
; sta $d020
ldx #$0a
dex
bne *-$01
bit $ea
nop
lda $d012
cmp #rstr2p+$05
beq *+$02
; sta $d020
ldx #$09
dex
bne *-$01
nop
nop
nop
nop
lda $d012
cmp #rstr2p+$06
beq *+$02
; sta $d020
; Lining things up for before first scanline of the scroller
ldx #$0a
dex
bne *-$01
lda #$34
sta $d011
ldx #$03
dex
bne *-$01
; Set the sprite Y positions for the lower scroller
lda #$fa
sta $d001
sta $d003
sta $d005
sta $d007
sta $d009
sta $d00b
sta $d00d
sta $d00f
nop
nop
lda #$00
sta $d021
jsr splitter
; Update the left hand half of the upper scroller's colour effect
lda pulse_tmr_1
lsr
cmp #$10
bcc *+$04
lda #$00
tax
lda colour_pulse_2+$08,x
sta split_1_11+$01
lda colour_pulse_2+$07,x
sta split_1_0f+$01
lda colour_pulse_2+$06,x
sta split_1_0d+$01
lda colour_pulse_2+$05,x
sta split_1_0b+$01
lda colour_pulse_2+$04,x
sta split_1_09+$01
lda colour_pulse_2+$03,x
sta split_1_07+$01
lda colour_pulse_2+$02,x
sta split_1_05+$01
lda colour_pulse_2+$01,x
sta split_1_03+$01
lda colour_pulse_2+$00,x
sta split_1_01+$01
; Update the right hand half of the upper scroller's colour effect
lda pulse_tmr_2
lsr
cmp #$10
bcc *+$04
lda #$00
tax
lda colour_pulse_1+$00,x
sta split_2_11+$01
lda colour_pulse_1+$01,x
sta split_2_0f+$01
lda colour_pulse_1+$02,x
sta split_2_0d+$01
lda colour_pulse_1+$03,x
sta split_2_0b+$01
lda colour_pulse_1+$04,x
sta split_2_09+$01
lda colour_pulse_1+$05,x
sta split_2_07+$01
lda colour_pulse_1+$06,x
sta split_2_05+$01
lda colour_pulse_1+$07,x
sta split_2_03+$01
lda colour_pulse_1+$08,x
sta split_2_01+$01
; Set up for the first raster split
lda #$01
sta rn
lda #rstr1p
sta $d012
; Exit IRQ interrupt
ea31 pla
tay
pla
tax
pla
nmi rti
; Reset the scrolling message
reset lda #<scroll_text
sta mread+$01
lda #>scroll_text
sta mread+$02
rts
; Splitter code (called twice per frame)
splitter lda #$18
bit $ea
; Scanline $00
ldx #split1_col_00
ldy #split2_col_00
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_01 ldx #$01
sta $d016
; Scanline $01
sty $d02c
sty $d02d
sty $d02e
split_2_01 ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_01
sta $d016
; Scanline $02
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_01
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_03 ldx #$01
sta $d016
; Scanline $03
sty $d02c
sty $d02d
sty $d02e
split_2_03 ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_02
sta $d016
; Scanline $04
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_02
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_05 ldx #$01
sta $d016
; Scanline $05
sty $d02c
sty $d02d
sty $d02e
split_2_05 ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_03
sta $d016
; Scanline $06
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_03
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_07 ldx #$01
sta $d016
; Scanline $07
sty $d02c
sty $d02d
sty $d02e
split_2_07 ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_04
sta $d016
; Scanline $08
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_04
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_09 ldx #$01
sta $d016
; Scanline $09
sty $d02c
sty $d02d
sty $d02e
split_2_09 ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_05
sta $d016
; Scanline $0a
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_05
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_0b ldx #$01
sta $d016
; Scanline $0b
sty $d02c
sty $d02d
sty $d02e
split_2_0b ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_06
sta $d016
; Scanline $0c
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_06
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_0d ldx #$01
sta $d016
; Scanline $0d
sty $d02c
sty $d02d
sty $d02e
split_2_0d ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_07
sta $d016
; Scanline $0e
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_07
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_0f ldx #$01
sta $d016
; Scanline $0f
sty $d02c
sty $d02d
sty $d02e
split_2_0f ldy #$01
stx $d027
stx $d028
stx $d029
stx $d02a
sty $d02b
dec $d016
ldx #split1_col_08
sta $d016
; Scanline $10
sty $d02c
sty $d02d
sty $d02e
ldy #split2_col_08
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
split_1_11 ldx #$01
sta $d016
; Scanline $10
sty $d02c
sty $d02d
sty $d02e
split_2_11 ldy #$09
stx $d027
stx $d028
stx $d029
sty $d02a
stx $d02b
dec $d016
nop
sta $d016