29 lines
504 B
ArmAsm
29 lines
504 B
ArmAsm
// #LAYOUT# STD * #TAKE
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// #LAYOUT# * KERNAL_0 #TAKE
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// #LAYOUT# * * #IGNORE
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//
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// Official Kernal routine, described in:
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//
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// - [RG64] C64 Programmers Reference Guide - page 288
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// - [CM64] Computes 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 MEMSIZK+1
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ldx MEMSIZK+0
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// FALLTROUGH
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memtop_set: // for compatibility reasons this has to start at $FE2D
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sty MEMSIZK+1
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stx MEMSIZK+0
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rts
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