2000-10-25 19:53:22 +00:00
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;
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2003-10-28 08:47:47 +00:00
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; Piotr Fusik, 24.10.2003
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; originally by Ullrich von Bassewitz
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2000-10-25 19:53:22 +00:00
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;
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; CC65 runtime: Decrement the stackpointer by value in y
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;
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2003-10-28 08:47:47 +00:00
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.export subysp
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.importzp sp
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2000-10-25 19:53:22 +00:00
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.proc subysp
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2003-10-28 08:47:47 +00:00
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tya
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eor #$ff
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2000-10-25 19:53:22 +00:00
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sec
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2003-10-28 08:47:47 +00:00
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adc sp
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sta sp
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2000-10-25 19:53:22 +00:00
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bcs @L1
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dec sp+1
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2003-10-28 08:47:47 +00:00
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@L1: rts
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2000-10-25 19:53:22 +00:00
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.endproc
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