30 lines
435 B
ArmAsm
30 lines
435 B
ArmAsm
#if ROM_LAYOUT_STD || (ROM_LAYOUT_M65 && SEGMENT_KERNAL_0)
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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 287/288
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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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MEMBOT:
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bcc membot_set
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ldy MEMSTR+1
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ldx MEMSTR+0
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// FALLTROUGH
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membot_set:
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sty MEMSTR+1
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stx MEMSTR+0
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rts
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#endif // ROM layout
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