64 lines
1.1 KiB
ArmAsm
64 lines
1.1 KiB
ArmAsm
; Apple II graphics/music in 1k
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; by deater (Vince Weaver) <vince@deater.net>
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; Zero Page
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.include "zp.inc"
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.include "hardware.inc"
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; for a 256 entry we need to fit in 252 bytes
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; 310 bytes -- initial
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; 268 bytes -- strip out interrupts
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; 262 bytes -- simplify init
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; 261 bytes -- optimize init more
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; 253 bytes -- optimize var init
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; 252 bytes -- bne vs jmp
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; 250 bytes -- song only has 16 notes so can never be negative
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; 249 bytes -- make terminating value $80 instead of $FF
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; 247 bytes -- combine note loop. makes song a bit faster
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; 245 bytes -- try to optimize writing out volume
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; 255 bytes -- add in some visualization
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; 252 bytes -- re-arrange decode code
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d2:
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;===================
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; music Player Setup
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tracker_song = peasant_song
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; assume mockingboard in slot#4
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; inline mockingboard_init
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.include "mockingboard_init.s"
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.include "tracker_init.s"
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jsr SETGR ; enable lo-res graphics
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game_loop:
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; typically A=0, X=FF, Y=0 here
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; play a frame of music
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.include "play_frame.s"
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.include "ay3_write_regs.s"
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; delay 20Hz, or 1/20s = 50ms
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lda #140
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jsr WAIT
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lda #140
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jsr WAIT
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lda #140
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jsr WAIT
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beq game_loop
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; music
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.include "mA2E_4.s"
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