-
Notifications
You must be signed in to change notification settings - Fork 0
Expand file tree
/
Copy pathhellgate.asm
More file actions
4337 lines (4000 loc) · 95.6 KB
/
hellgate.asm
File metadata and controls
4337 lines (4000 loc) · 95.6 KB
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
;
; **** ZP FIELDS ****
;
f3E = $3E
;
; **** ZP ABSOLUTE ADRESSES ****
;
zpLo = $00
zpHi = $01
screenPtrXPos = $02
screenPtrYPPos = $03
charToDraw = $04
colorToDraw = $05
bulletGroup = $06
pulsingColorArrayIndex = $07
a08 = $08
a09 = $09
a0A = $0A
a0B = $0B
dsplyCurScoreClrPtrLo = $0E
dsplyCurScoreClrPtrHi = $0F
a10 = $10
a11 = $11
a12 = $12
a13 = $13
a14 = $14
a15 = $15
a16 = $16
a17 = $17
a18 = $18
a19 = $19
a1A = $1A
joystickInput = $1B
a1C = $1C
a1D = $1D
a1E = $1E
a1F = $1F
a20 = $20
a21 = $21
previousColorPulse = $22
dsplyCurScorePtrLo = $23
dsplyCurScorePtrHi = $24
a26 = $26
a27 = $27
a28 = $28
a29 = $29
a2A = $2A
a2B = $2B
a2C = $2C
a2D = $2D
a2E = $2E
a2F = $2F
a30 = $30
curEnergyBarLevel = $31
a32 = $32
a33 = $33
a34 = $34
a35 = $35
inAttractMode = $36
currentPlayer = $37
a38 = $38
shipsLeft = $39
zapsLeft = $3A
a50 = $50
sequenceTimer1 = $51
titleSequenceTimer2 = $52
sequenceTimer3 = $53
a54 = $54
a55 = $55
aC5 = $C5
;
; **** ZP POINTERS ****
;
;
; **** FIELDS ****
;
SCREEN_PTR_LO = $0340
SCREEN_PTR_HI = $0360
highScoreTableStorage = $3D00
f3D01 = $3D01
f3D02 = $3D02
f3E00 = $3E00
enemyXPosArray = $3E20
enemyYPosArray = $3E40
alienAnimationSeqPtr = $3E60
f3E80 = $3E80
f3EA0 = $3EA0
enemyCharArray = $3EC0
f3EE0 = $3EE0
bulletColorArray = $3FA0
bulletGroupArray = $3FB0
bulletXPosArray = $3FC0
bulletYPosArray = $3FD0
f3FE0 = $3FE0
bulletCharArray = $3FF0
dsplyPlasmoZapsLabel = $96BE
f96D4 = $96D4
f96DC = $96DC
f96E1 = $96E1
f96E6 = $96E6
fC000 = $C000
;
; **** ABSOLUTE ADRESSES ****
;
screenPtrXPos91 = $0291
WaitCtr2 = $1108
WaitCtr1 = $1109
a113F = $113F
a1140 = $1140
a96D3 = $96D3
;
; **** POINTERS ****
;
p02 = $0002
p0B = $000B
p0200 = $0200
p0203 = $0203
p0505 = $0505
p0900 = $0900
p0901 = $0901
p0A02 = $0A02
p0A07 = $0A07
p0B0A = $0B0A
p0B0C = $0B0C
p0C02 = $0C02
p0C03 = $0C03
p0C13 = $0C13
p0E02 = $0E02
p0E13 = $0E13
SCREEN_RAM = $1000
dsplyEntryLevel = SCREEN_RAM + $264
dsplyPlayers = SCREEN_RAM + $270
dsplyZapsLeft = SCREEN_RAM + $2C2
dsplyLaserheadsLeft = SCREEN_RAM + $2D4
dsplyEnergyBar = SCREEN_RAM + $2C3
p4C0B = $4C0B
p6301 = $6301
BLACK = $00
WHITE = $01
RED = $02
CYAN = $03
PURPLE = $04
BLUE = $06
YELLOW = $07
LTYELLOW = $0F
;
; **** EXTERNAL JUMPS ****
;
;
; **** PREDEFINED LABELS ****
;
RAM_CINV = $0314
VICCR0 = $9000
VICCR1 = $9001
VICCR2 = $9002
VICCR3 = $9003
VICCR4 = $9004
VICCR5 = $9005
VICCRA = $900A
VICCRB = $900B
VICCRC = $900C
VICCRD = $900D
VICCRE = $900E
VICCRF = $900F
VIA1IER = $911E
VIA1PA2 = $911F
VIA2PB = $9120
VIA2DDRB = $9122
ROM_IRQ = $EABF
* = $1201
;------------------------------------------------
; SYS 6656 (LaunchGame $1A00) (Launch)
; Jumps to LaunchGame
;------------------------------------------------
.BYTE $0B,$12,$0A,$00,$9E,$36,$36,$35,$36,$00,$00,$00
.include "padding.asm"
.include "charset.asm"
; Redundant data
.BYTE $00,$00,$00,$00,$00,$00,$00,$C1
LaunchGame
LDA #$02
p1A02 STA VIA1IER ;$911E - interrupt enable register (IER)
LDA #$80
STA screenPtrXPos91
JMP InitializeAudioAndVideo
;------------------------------------------------
; We write to the screen by writing to address $1E00-$1FFF.
; Use SCREEN_PTR_LO/SCREEN_PTR_HI as an array that contains
; pointers to the addresses in screen memory.
;------------------------------------------------
InitScreenPtrArray
LDA #>SCREEN_RAM
STA zpHi
LDA #<SCREEN_RAM
STA zpLo
LDX #$00
b1A17 LDA zpLo
STA SCREEN_PTR_LO,X
LDA zpHi
STA SCREEN_PTR_HI,X
LDA zpLo
CLC
ADC #$19
STA zpLo
LDA zpHi
ADC #$00
STA zpHi
INX
CPX #$20
BNE b1A17
RTS
;------------------------------------------------
; Screen_GetPtr
;------------------------------------------------
Screen_GetPtr
LDX screenPtrYPPos
LDY screenPtrXPos
LDA SCREEN_PTR_LO,X
STA zpLo
LDA SCREEN_PTR_HI,X
STA zpHi
RTS
;------------------------------------------------
; GetCharAtCurrentPos
;------------------------------------------------
GetCharAtCurrentPos
JSR Screen_GetPtr
LDA (zpLo),Y
b1A48 RTS
;------------------------------------------------
; DrawCharacter
;------------------------------------------------
DrawCharacter
LDA screenPtrXPos
CMP #$28
BPL b1A48
TXA
PHA
TYA
PHA
JSR Screen_GetPtr
LDA charToDraw
STA (zpLo),Y
LDA zpHi
CLC
ADC #$84
STA zpHi
LDA colorToDraw
STA (zpLo),Y
PLA
TAY
PLA
TAX
RTS
;------------------------------------------------
; ClearScreen
;------------------------------------------------
ClearScreen
LDX #$00
b1A6C LDA #$20
STA SCREEN_RAM,X
STA SCREEN_RAM + $100,X
STA SCREEN_RAM + $200,X
STA SCREEN_RAM + $300,X
DEX
BNE b1A6C
RTS
a1A7E .TEXT "0"
a1A7F .TEXT $08
a1A80 .TEXT " "
a1A81 .TEXT $06
highScoreTable .TEXT "0010000LLA0009000MA 0008000YAK0007000DOE"
.TEXT "0006000VIC0005000UNA0004000EWE0003000YAK"
;------------------------------------------------
; InitializeAudioAndVideo
;------------------------------------------------
InitializeAudioAndVideo
JSR InitScreenPtrArray
JSR ClearScreen
LDA #$19
STA a33
LDA #$01
STA a34
LDA #$0B
STA a35
LDX #$00
STX inAttractMode
b1AE8 LDA highScoreTable,X
STA highScoreTableStorage,X
INX
CPX #$50
BNE b1AE8
LDA #$D5
STA dsplyCurScorePtrLo
LDA #$12
STA dsplyCurScorePtrHi
LDA #$08
STA VICCRF ;$900F - screen colors: background, border & inverse
; Bits 0 to 3 (i.e. the D in $CD) determine which address character
; set is stored at. So D points to $1400. The maps is as follows:
;Bits Address
;0000 8000
;0001 8400
;0010 8800
;0011 8C00
;1000 0000
;1100 1000
;1101 1400
;1110 1800
;1111 1C00
LDA #$CD ; $D translates as charcters starting at $1400
STA VICCR5 ;$9005 - screen map & character map address
LDA #$19
STA VICCR2 ;$9002 - number of columns, part os screen map addr.
LDA #$3C
STA VICCR3 ;$9003 - number of lines, part of raster location (bit 8)
LDA #$0A
STA VICCR0 ;$9000 - left edge of picture & interlace switch
; Set the IRQ interrupt handlet to ColorPulseScoreAndPlasmoLabel
SEI
LDA #<ColorPulseScoreAndPlasmoLabel
STA RAM_CINV
LDA #>ColorPulseScoreAndPlasmoLabel
STA RAM_CINV + $01
CLI
LDA #$18
STA VICCR1 ;$9001 - vertical picture origin
LDA #$00
STA a32
STA currentPlayer
JMP RunTitleSequence
;-------------------------------
; SetupGameScreen
;-------------------------------
SetupGameScreen
JSR DrawScreenInterstitialEffect
JSR DrawLaserBasesAndStrapLine
LDA inAttractMode
BEQ b1B3F
JSR UpdateScrPtrYPosWithX
AND #$0F
STA a32
b1B3F LDA #$33
STA zapsLeft
LDA #$34 ; 4 ships
STA shipsLeft
LDA a32
STA a38
;-------------------------------
; EnterNextLevel
;-------------------------------
EnterNextLevel
LDA #$06
STA a1E
LDA #$0F
STA VICCRE ;$900E - sound volume
JSR ClearFullScreen
LDA #$01
STA a21
STA previousColorPulse
STA a20
LDA #$00
LDX #$00
b1B63 STA bulletColorArray,X
INX
CPX #$10
BNE b1B63
STA joystickInput
STA a50
LDA #<p6301
STA a2B
LDA #>p6301
STA a2C
LDA #$2F
STA a2D
LDA a32
BEQ b1B8B
TAX
b1B80 JSR WasteSomeCycles
BNE b1B80
DEX
BNE b1B80
JSR WasteSomeCycles
b1B8B JSR PrepareToDieNewLevelEffect
JSR SetUpAliensAndLaserheads
JMP MainGameLoop
;------------------------------------------------
; DrawLaserBasesAndStrapLine
;------------------------------------------------
DrawLaserBasesAndStrapLine
; Draw Horizontal top & bottom bases
LDA #<p02
STA screenPtrXPos
b1B98 LDA #>p02
STA screenPtrYPPos
LDA #BLUE
STA colorToDraw
LDA #$6E ; Horizontal Base
STA charToDraw
JSR DrawCharacter
LDA #$6D ; Horizontal Base
STA charToDraw
LDA #$1B
STA screenPtrYPPos
JSR DrawCharacter
INC screenPtrXPos
LDA screenPtrXPos
CMP #$17
BNE b1B98
; Draw vertical left & right bases
LDA #>p0200
STA screenPtrYPPos
b1BBE LDA #<p0200
STA screenPtrXPos
LDA #$70 ; Vertical Base
STA charToDraw
JSR DrawCharacter
DEC charToDraw ; Vertical Base
LDA #$18
STA screenPtrXPos
JSR DrawCharacter
INC screenPtrYPPos
LDA screenPtrYPPos
CMP #$1A
BNE b1BBE
; Draw straplines
LDA #$1C
STA screenPtrYPPos
LDA #$00
STA screenPtrXPos
LDA inAttractMode
BNE b1C0B
LDX #$00
b1BE8 LDA scoreLineText1,X
AND #$BF
STA charToDraw
LDA #YELLOW
STA colorToDraw
JSR DrawCharacter
INC screenPtrYPPos
LDA scoreLineText2,X
AND #$3F
STA charToDraw
JSR DrawCharacter
DEC screenPtrYPPos
INC screenPtrXPos
INX
CPX #$19
BNE b1BE8
b1C0B JSR ResetEnergyBar
JMP InitializeGameVariables
scoreLineText1 .BYTE $9D,$9E,$9F,$A0,$A1,$A2,$33,$20
.BYTE $20,$20,$20,$20,$20,$20,$20,$20
.BYTE $20,$20,$20,$20,$20,$20,$20,$A3
.BYTE $34
scoreLineText2 .TEXT "0000000 HELL$GATE 0000000"
;-------------------------------
; InitializeGameVariables
;-------------------------------
InitializeGameVariables
LDA #$01
STA a11
STA a16
LDA #$16
STA a10
LDA #$02
STA a17
LDA #>p1917
STA a15
LDA #<p1917
STA a14
LDA #>p1A02
STA a13
LDA #<p1A02
STA a12
LDA #$00
STA a18
STA a19
STA a1A
RTS
;------------------------------------------------
; SetUpAliensAndLaserheads
;------------------------------------------------
SetUpAliensAndLaserheads
LDA #$A0
STA VICCRD ;$900D - frequency of sound osc.4 (noise)
JSR PerformAlienAnimation
LDX #$00
LDA #$00
b1C76 STA f3E00,X
INX
BNE b1C76
LDA #$00
STA VICCRD ;$900D - frequency of sound osc.4 (noise)
JSR MoveLaserheads
JMP PlayNewLevelSounds
;Returns
;------------------------------------------------
; MoveLaserheads
;------------------------------------------------
MoveLaserheads
LDA a18
BEQ b1C8E
JMP LeftRightLaserheadFirstFrame
b1C8E LDA #leftLaserheadFull
JSR UpdateCharToDraw
LDA a16
STA screenPtrXPos
LDA #YELLOW
STA colorToDraw
LDA a17
STA screenPtrYPPos
JSR MoveLaserhead
LDA #rightLaserheadFull
JSR UpdateCharToDraw
LDA a14
STA screenPtrXPos
LDA #PURPLE
STA colorToDraw
LDA a15
STA screenPtrYPPos
JSR MoveLaserhead
JMP MoveTopBottomLaserheads
; Returns from MoveLaserhead
;------------------------------------------------
; UpdateCharToDraw
;------------------------------------------------
UpdateCharToDraw
LDY a1A
CPY #$01
BNE b1CC1
LDA #$20
b1CC1 STA charToDraw
RTS
;-------------------------------
; LeftRightLaserheadFirstFrame
;-------------------------------
LeftRightLaserheadFirstFrame
LDA #leftLaserheadTopHalf
JSR UpdateCharToDraw
LDA #YELLOW
STA colorToDraw
LDA a16
STA screenPtrXPos
LDA a17
STA screenPtrYPPos
JSR MoveLaserhead
INC charToDraw
LDA charToDraw
JSR UpdateCharToDraw
INC screenPtrYPPos
JSR MoveLaserhead
LDA #rightLaserheadTopHalf
JSR UpdateCharToDraw
LDA #PURPLE
STA colorToDraw
LDA a14
STA screenPtrXPos
LDA a15
STA screenPtrYPPos
JSR MoveLaserhead
INC charToDraw
LDA charToDraw
JSR UpdateCharToDraw
INC screenPtrYPPos
JSR MoveLaserhead
;-------------------------------
; MoveTopBottomLaserheads
;-------------------------------
MoveTopBottomLaserheads
LDA a19
BEQ b1D0B
JMP BottomTopFirstFrame
b1D0B LDA #bottomLaserheadFull
JSR UpdateCharToDraw
LDA #YELLOW
STA colorToDraw
LDA a12
STA screenPtrXPos
LDA a13
STA screenPtrYPPos
JSR MoveLaserhead
LDA #topLaserheadFull
JSR UpdateCharToDraw
LDA #PURPLE
STA colorToDraw
LDA a10
STA screenPtrXPos
LDA a11
STA screenPtrYPPos
JMP MoveLaserhead
; Returns
;-------------------------------
; BottomTopFirstFrame
;-------------------------------
BottomTopFirstFrame
LDA #bottomLaserheadLeftHalf
JSR UpdateCharToDraw
LDA #YELLOW
STA colorToDraw
LDA a12
STA screenPtrXPos
LDA a13
STA screenPtrYPPos
JSR MoveLaserhead
INC charToDraw
LDA charToDraw
JSR UpdateCharToDraw
INC screenPtrXPos
JSR MoveLaserhead
LDA #PURPLE
STA colorToDraw
LDA a10
STA screenPtrXPos
LDA a11
STA screenPtrYPPos
LDA #topLaserheadRightHalf
JSR UpdateCharToDraw
JSR MoveLaserhead
INC charToDraw
LDA charToDraw
JSR UpdateCharToDraw
INC screenPtrXPos
JMP MoveLaserhead
;------------------------------------------------
; GetJoystickInput
;------------------------------------------------
GetJoystickInput
SEI
LDX #$7F
STX VIA2DDRB ;$9122 - data direction register for port b
b1D79 LDY VIA2PB ;$9120 - port b I/O register
CPY VIA2PB ;$9120 - port b I/O register
BNE b1D79
LDX #$FF
STX VIA2DDRB ;$9122 - data direction register for port b
LDX #$F7
STX VIA2PB ;$9120 - port b I/O register
CLI
b1D8C LDA VIA1PA2 ;$911F - mirror of VIA1PA1 (CA1 & CA2 unaffected)
CMP VIA1PA2 ;$911F - mirror of VIA1PA1 (CA1 & CA2 unaffected)
BNE b1D8C
PHA
AND #$1C
LSR
CPY #$80
BCC b1D9E
ORA #$10
b1D9E TAY
PLA
AND #$20
CMP #$20
TYA
ROR
EOR #$8F
STA joystickInput
LDA inAttractMode
BEQ b1DBB
LDA joystickInput
AND #$80
BEQ b1DB7
JMP BackToSecondTitleScreen
b1DB7 LDA #$85
STA joystickInput
b1DBB RTS
;------------------------------------------------
; MoveLaserheadsDown
;------------------------------------------------
MoveLaserheadsDown
LDA a17
CMP #$19
BNE b1DCC
LDA a17
PHA
LDA a15
STA a17
PLA
STA a15
b1DCC INC a18
LDA a18
CMP #$02
BNE b1DD8
LDA #$00
STA a18
b1DD8 LDA a18
BEQ b1DDF
DEC a15
RTS
b1DDF INC a17
RTS
;------------------------------------------------
; MoveLaserheadsUp
;------------------------------------------------
MoveLaserheadsUp
LDA a17
CMP #$02
BNE b1DF2
LDA a17
PHA
LDA a15
STA a17
PLA
STA a15
b1DF2 DEC a18
LDA a18
CMP #$FF
BNE b1DFE
LDA #$01
STA a18
b1DFE LDA a18
BEQ b1E05
DEC a17
RTS
b1E05 INC a15
RTS
;------------------------------------------------
; MoveLaserheadsRight
;------------------------------------------------
MoveLaserheadsRight
LDA a12
CMP #$16
BNE b1E18
LDA a12
PHA
LDA a10
STA a12
PLA
STA a10
b1E18 INC a19
LDA a19
AND #$01
STA a19
BEQ b1E25
DEC a10
RTS
b1E25 INC a12
RTS
;------------------------------------------------
; MoveLaserheadsLeft
;------------------------------------------------
MoveLaserheadsLeft
LDA a12
CMP #$02
BNE b1E38
LDA a12
PHA
LDA a10
STA a12
PLA
STA a10
b1E38 INC a19
LDA a19
AND #$01
STA a19
BEQ b1E45
DEC a12
RTS
b1E45 INC a10
;------------------------------------------------
; CheckJoystickInput
;------------------------------------------------
b1E47 RTS
CheckJoystickInput
DEC a1C
BNE b1E47
LDA a1A7E
STA a1C
JSR DoSomeAnimation
LDA #$01
STA a2A
JSR MoveLaserheads
DEC a2A
JSR GetJoystickInput
LDA joystickInput
AND #$0F
BEQ b1E47
LDA #$01
STA a1A
JSR MoveLaserheads
DEC a1A
LDA joystickInput
AND #$01 ; Up
BEQ b1E78
JSR MoveLaserheadsUp
b1E78 LDA joystickInput
AND #$02 ; Down
BEQ b1E81
JSR MoveLaserheadsDown
b1E81 LDA joystickInput
AND #$04 ; Left
BEQ b1E8A
JSR MoveLaserheadsLeft
b1E8A LDA joystickInput
AND #$08 ; Right
BEQ b1E93
JSR MoveLaserheadsRight
b1E93 JMP MoveLaserheads
;------------------------------------------------
; MainGameLoop
;------------------------------------------------
MainGameLoop
JSR CheckJoystickInput
JSR PlayBackgroundSounds
JSR CheckFireBullets
JSR UpdateEnemyPositions
JMP MainGameLoop
;------------------------------------------------
; DrawBullets4
;------------------------------------------------
DrawBullets4
INC f3FE0,X
LDA f3FE0,X
AND #$01
STA f3FE0,X
BEQ b1EC9
LDA bulletCharArray,X
STA charToDraw
INC charToDraw
LDA bulletXPosArray,X
STA screenPtrXPos
LDA bulletYPosArray,X
STA screenPtrYPPos
JSR DrawBulletImpl
JMP DrawCharacter
b1EC9 LDA bulletXPosArray,X
STA screenPtrXPos
LDA bulletYPosArray,X
STA screenPtrYPPos
LDA #$20
STA charToDraw
JSR DrawBulletImpl
JSR DrawCharacter
INC screenPtrXPos
INC bulletXPosArray,X
DEC bulletColorArray,X
BNE b1EE8
RTS
b1EE8 LDA bulletCharArray,X
STA charToDraw
JSR DrawBulletImpl
JMP DrawCharacter
;------------------------------------------------
; DrawBullets3
;------------------------------------------------
DrawBullets3
DEC f3FE0,X
LDA f3FE0,X
AND #$01
STA f3FE0,X
BNE b1F15
LDA bulletXPosArray,X
STA screenPtrXPos
LDA bulletYPosArray,X
STA screenPtrYPPos
LDA bulletCharArray,X
STA charToDraw
JSR DrawBulletImpl
JMP DrawCharacter
b1F15 LDA bulletXPosArray,X
STA screenPtrXPos
LDA bulletYPosArray,X
STA screenPtrYPPos
LDA #$20
STA charToDraw
JSR DrawBulletImpl
JSR DrawCharacter
DEC screenPtrXPos
DEC bulletXPosArray,X
DEC bulletColorArray,X
BNE b1F34
RTS
b1F34 LDA bulletCharArray,X
STA charToDraw
INC charToDraw
JSR DrawBulletImpl
JMP DrawCharacter
;------------------------------------------------
; DrawBullets1
;------------------------------------------------
DrawBullets1
DEC f3FE0,X
LDA f3FE0,X
AND #$01
STA f3FE0,X
BNE b1F63
LDA bulletXPosArray,X
STA screenPtrXPos
LDA bulletYPosArray,X
STA screenPtrYPPos
LDA bulletCharArray,X
STA charToDraw
JSR DrawBulletImpl
JMP DrawCharacter
b1F63 LDA bulletXPosArray,X
STA screenPtrXPos
LDA bulletYPosArray,X
STA screenPtrYPPos
LDA #$20
STA charToDraw
JSR DrawBulletImpl
JSR DrawCharacter
DEC screenPtrYPPos
DEC bulletYPosArray,X
DEC bulletColorArray,X
BNE b1F82
RTS
b1F82 LDA bulletCharArray,X
STA charToDraw
INC charToDraw
JSR DrawBulletImpl
JMP DrawCharacter
;------------------------------------------------
; DrawBullets2
;------------------------------------------------
DrawBullets2
INC f3FE0,X
LDA f3FE0,X
AND #$01
STA f3FE0,X
BEQ b1FB3