42 lines
827 B
ArmAsm
42 lines
827 B
ArmAsm
; Reads from wave RAM while playing, each time 2
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; clocks later.
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;.define REQUIRE_DMG 1
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;.define REQUIRE_CGB 1
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.include "shell.inc"
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.include "apu.s"
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main:
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wreg NR51,0 ; mute sound
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loop_n_times test,69
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check_crc_dmg_cgb $118A3620,$270DA9A3
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jp tests_passed
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test:
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add $99
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ld b,a
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; Reload wave and have its first
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; sample read occur 2 clocks earlier
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; each loop iteration
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ld hl,wave
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call load_wave
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wreg NR30,$80 ; enable
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wreg NR32,$00 ; silent
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ld a,b
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sta NR33 ; period
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wreg NR34,$87 ; start
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; Read from wave
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wreg NR33,-2 ; period = 4
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delay_clocks 176
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lda WAVE
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call print_a
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ret
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wave:
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.byte $00,$11,$22,$33,$44,$55,$66,$77
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.byte $88,$99,$AA,$BB,$CC,$DD,$EE,$FF
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