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54 lines
780 B
ArmAsm
54 lines
780 B
ArmAsm
;
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; Ullrich von Bassewitz, 07.12.1998
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;
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; Copy the data segment from the LOAD to the RUN location
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;
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.export copydata
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.import __DATA_LOAD__, __DATA_RUN__, __DATA_SIZE__
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.importzp ptr1, ptr2
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copydata:
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lda #<__DATA_LOAD__ ; Source pointer
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sta ptr1
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lda #>__DATA_LOAD__
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sta ptr1+1
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lda #<__DATA_RUN__ ; Target pointer
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sta ptr2
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lda #>__DATA_RUN__
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sta ptr2+1
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ldy #$00
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ldx #>__DATA_SIZE__ ; Get page count
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beq @L2 ; No full pages
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; Copy full pages
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@L1: lda (ptr1),y
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sta (ptr2),y
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iny
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bne @L1
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inc ptr1+1
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inc ptr2+1 ; Bump pointers
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dex
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bne @L1
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; Copy last page (remember: y contains zero)
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@L2: ldx #<__DATA_SIZE__ ; Get remaining bytes
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beq @L4
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@L3: lda (ptr1),y
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sta (ptr2),y
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iny
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dex
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bne @L3
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; Done
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@L4: rts
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