mirror of https://github.com/cc65/cc65.git
30 lines
666 B
ArmAsm
30 lines
666 B
ArmAsm
;
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; Colin Leroy-Mira <colin@colino.net>, 2024
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;
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; unsigned char __fastcall__ detect_iigs(unsigned char speed)
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;
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.export _set_iigs_speed
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.import ostype, return0
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.include "apple2.inc"
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.include "accelerator.inc"
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_set_iigs_speed:
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tax ; Keep parameter
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lda ostype ; Return if not IIgs
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bmi :+
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jmp return0
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: lda CYAREG
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cpx #SPEED_SLOW
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beq :+
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ora #%10000000
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bne set_speed
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: and #%01111111
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set_speed:
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sta CYAREG
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txa
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ldx #$00
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rts
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