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30 lines
1.0 KiB
ArmAsm
30 lines
1.0 KiB
ArmAsm
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.include "pcengine.inc"
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.export psg_init
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psg_init:
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clx
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stx $0800 ; Select channel
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psg_clear_loop:
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stz $0801 ; Clear global balance
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stz $0802 ; Clear frequency LSB
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stz $0803 ; Clear frequency MSB
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stz $0804 ; Clear volume
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stz $0805 ; Clear balance
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stz $0807 ; Clear noise control
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stz $0808 ; Clear LFO frequency
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stz $0809 ; Clear LFO control
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cly
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psg_clear_waveform: stz $0806 ; Clear waveform byte
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iny
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cpy #$20
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bne psg_clear_waveform
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inx
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cpx #$06
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bne psg_clear_loop
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rts
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