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42 lines
458 B
ArmAsm
42 lines
458 B
ArmAsm
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;
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; Ullrich von Bassewitz, 23.09.1998
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;
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; unsigned readjoy (unsigned char joy);
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;
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.export _readjoy
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.include "c64.inc"
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.proc _readjoy
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tax ; Joystick number into X
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bne joy2
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; Read joystick 1
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joy1: lda #$7F
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sei
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sta CIA1_PRA
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lda CIA1_PRB
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cli
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and #$1F
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eor #$1F
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rts
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; Read joystick 2
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joy2: ldx #0
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lda #$E0
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ldy #$FF
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sta CIA1_DDRA
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lda CIA1_PRA
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sty CIA1_DDRA
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and #$1F
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eor #$1F
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rts
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.endproc
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