mirror of
https://github.com/cc65/cc65.git
synced 2024-08-29 09:29:19 +00:00
54 lines
780 B
ArmAsm
54 lines
780 B
ArmAsm
;
|
|
; Ullrich von Bassewitz, 07.12.1998
|
|
;
|
|
; Copy the data segment from the LOAD to the RUN location
|
|
;
|
|
|
|
.export copydata
|
|
.import __DATA_LOAD__, __DATA_RUN__, __DATA_SIZE__
|
|
.importzp ptr1, ptr2
|
|
|
|
|
|
copydata:
|
|
lda #<__DATA_LOAD__ ; Source pointer
|
|
sta ptr1
|
|
lda #>__DATA_LOAD__
|
|
sta ptr1+1
|
|
|
|
lda #<__DATA_RUN__ ; Target pointer
|
|
sta ptr2
|
|
lda #>__DATA_RUN__
|
|
sta ptr2+1
|
|
|
|
ldy #$00
|
|
ldx #>__DATA_SIZE__ ; Get page count
|
|
beq @L2 ; No full pages
|
|
|
|
; Copy full pages
|
|
|
|
@L1: lda (ptr1),y
|
|
sta (ptr2),y
|
|
iny
|
|
bne @L1
|
|
inc ptr1+1
|
|
inc ptr2+1 ; Bump pointers
|
|
dex
|
|
bne @L1
|
|
|
|
; Copy last page (remember: y contains zero)
|
|
|
|
@L2: ldx #<__DATA_SIZE__ ; Get remaining bytes
|
|
beq @L4
|
|
|
|
@L3: lda (ptr1),y
|
|
sta (ptr2),y
|
|
iny
|
|
dex
|
|
bne @L3
|
|
|
|
; Done
|
|
|
|
@L4: rts
|
|
|
|
|