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At power-on or reset time, you must initialize one of the Copper
 location registers (COP1LC or COP2LC)  and write to its  strobe address 
before Copper DMA is turned on. This ensures a known start address and
known state. Usually,  COP1LC  is used because this particular register is
reused during each vertical blanking  time. The following sequence of
instructions shows how to initialize a  location register . It is assumed
that the user has already created the correct  Copper instruction list  at
location "mycoplist."

; Install the copper list
     LEA     CUSTOM,a1           ; a1 = address of custom chips
     LEA     MYCOPLIST(pc),a0    ; Address of our copper list
     MOVE.L  a0,COP1LC(a1)       ; Write whole longword address
     MOVE.W  COPJMP1(a1),d0      ; Causes copper to load PC from  COP1LC 
; Then enable copper and raster dma

Now, if the contents of  COP1LC  are not changed, every time
 vertical blanking  occurs the Copper will restart at the same location
for each subsequent video screen. This forms a repeatable loop which, if
the list is correctly formulated, will cause the displayed screen to be

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