25 lines
340 B
ArmAsm
25 lines
340 B
ArmAsm
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//
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// Official Kernal routine, described in:
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//
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// - [RG64] C64 Programmer's Reference Guide - page 288
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// - [CM64] Compute's Mapping the Commodore 64 - page 240
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//
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// CPU registers that has to be preserved (see [RG64]): .A
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//
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MEMTOP:
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bcc memtop_set
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ldy MEMSIZ+1
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ldx MEMSIZ+0
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rts
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memtop_set:
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sty MEMSIZ+1
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stx MEMSIZ+0
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rts
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