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37 lines
543 B
ArmAsm
37 lines
543 B
ArmAsm
;
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; Ullrich von Bassewitz, 2003-04-13
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;
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; clock_t clock (void);
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;
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.export _clock
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.import negax
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.importzp sreg
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.include "atmos.inc"
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.proc _clock
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; Clear the timer high 16 bits
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ldy #$00
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sty sreg
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sty sreg+1
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; Read the timer
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sei ; Disable interrupts
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lda TIMER3
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ldx TIMER3+1
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cli ; Reenable interrupts
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; Since the timer is counting downwards, return the negated value
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jmp negax
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.endproc
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