acme/ACME_Lib/cbm/c64/memcopy.a

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;ACME 0.96.4
!ifdef lib_cbm_c64_memcopy_a !eof
lib_cbm_c64_memcopy_a = 1
; this macro inserts code to copy a memory block.
; it calls a function from the basic interpreter, so:
; - BASIC ROM must be banked in
; - the source block must be readable (so no RAM hidden under BASIC, Kernal, or I/O)
; - the target block must be writable (so no RAM hidden under I/O)
; higher addresses are copied first, so:
; - moving data to higher addresses works even if areas overlap
; - moving data to lower addresses only works if areas do not overlap
!macro basic_memcopy @src_start, @src_end, @target_start {
!addr @z_target_end = $58
!addr @z_src_end = $5a
!addr @z_src_start = $5f
!addr @fn = $a3bf
lda #<@src_start
ldx #>@src_start
sta @z_src_start
stx @z_src_start + 1
lda #<@src_end
ldx #>@src_end
sta @z_src_end
stx @z_src_end + 1
lda #<(@target_start + @src_end - @src_start)
ldx #>(@target_start + @src_end - @src_start)
sta @z_target_end
stx @z_target_end + 1
jsr @fn
}