;*** Example for a simple Copperlist ***

     section main,code,chip

;CustomChip-Register

INTENA  = $9A       ; Interrupt-Enable-Register (write)
DMACON  = $96       ; DMA-control register (write)
COLOR00 = $0180     ; Color palette register 0
COLOR01 = $0182     ; Color palette register 1
VHPOSR  = $6

;Copper Register

COP1LC  = $80       ; Address of 1. Copper list
COP2LC  = $84       ; Address of 2. Copper list
COPJMP1 = $88       ; Jump to Copper list 1
COPJMP2 = $8A       ; Jump to Copper list 2

BPLCON0 = $100 ; Display control registers.
BPLCON1 = $102
BPLCON2 = $104

BPL1PTH = $0E0
BPL1PTL = $0E2
BPL1MOD = $108
DIWSTRT = $08E
DIWSTOP = $090
DDFSTRT = $092
DDFSTOP = $094

;CIA-A Port Register A (Mouse key)

CIAAPRA = $BFE001

;Exec Library Base Offsets

OpenLibrary = -552   ; Libname,Version / a1,d0
Forbid      = -132
Permit      = -138
AllocMem    = -198   ; Byte Size,Requirements / d0,d1
FreeMem     = -210   ; Memory Block,Byte Size / a1,d0

;Graphics base

StartList   = 38

;Other labels

Execbase    = 4
Chip        = 2 ; Constant to request CHIP RAM


;*** Initialise-Program ***

_start:
    move.l  Execbase,a6     ; We need exec to do anything!

; Request memory for Copperlist
    moveq   #CLsize,d0  ;Set Parameter for Allocmem
    moveq   #Chip,d1    ;Ask for Chip RAM
    jsr AllocMem(a6)    ;Request Memory
    move.l  d0,CLadr    ;Address of the RAM-area memory
    beq Ende        ;Error! -> End

;copy Copperlist to CLadr
    lea CLstart,a0
    move.l  CLadr,a1
    moveq   #CLsize-1,d0    ;Set loop value
CLcopy: move.b  (a0)+,(a1)+ ;Copy Copperlist byte for byte
    dbf d0,CLcopy

; Request memory for Single Bitplane.
    move.l  #BPMemSize,d0   ;Set Parameter for Allocmem
    moveq   #Chip,d1    ;Ask for Chip RAM
    jsr AllocMem(a6)    ;Request Memory
    move.l  d0,BPMemoryPtr  ;Address of the RAM-area memory
    beq Ende        ;Error! -> End

; Fill the bitplane with stripe pattern.
        move.l  BPMemoryPtr,a0
        move.l  #%1111001100110000,d0
        move.l  #(BPMemSize/2-1),d1
BPFill: move.w  d0,(a0)+
        dbf     d1,BPFill

; Put the address of the bitplane in the appropriate
; position in the copper list.
        move.l  CLadr,a1
        move.l  BPMemoryPtr,d0
        move.w  d0,6(a1) ; The low word goes in BPL1PTL
        swap    d0
        move.w  d0,2(a1) ; The high word goes in BPL1PTH (this works?)

;*** Main program ***

    jsr Forbid(a6)  ;Task Switching off

    lea $DFF000,a5  ;Custom chip base address.
    move.w  #$03a0,DMACON(a5) ;DMA off

        move.w  #%0001001000000000,BPLCON0(a5)
        ; Set one bitplane, and enable colour.

        move.w  #$3081,DIWSTRT(a5)
        move.w  #$30c1,DIWSTOP(a5)
        move.w  #$0038,DDFSTRT(a5)
        move.w  #$00d0,DDFSTOP(a5)

        move.w  #$0,BPLCON1(a5)   ; This is scrolling
        move.w  #$0,BPLCON2(a5)   ; This is sprite priority

        move.w  #$0,BPL1MOD(a5) ;modulo 0


; Initialise copperlist.
    move.l  CLadr,COP1LC(a5)  ;Address of the Copperlist to COP1LC
    clr.w   COPJMP1(a5)   ;Load copperlist in program counter

    move.w  #$8380,DMACON(a5) ;$8xxx means set... we're setting:
                                  ;Master, copper and bitplane.


    ; Turn off drive motors, all drives
    st.b $bfd100
        move.b #$87,$bfd100

;Wait for left mouse key

Wait:
    btst    #6,CIAAPRA  ;Bit test
    bne.s   Wait        ;Done? Else continue.
Wait2:
    btst    #6,CIAAPRA  ;Bit test again
    beq.s   Wait2       ;Done? Else continue.
    move.l  CLadr,-(a7)

    lea     4(a7),a7
Wait3:
    btst    #6,CIAAPRA  ;Bit test again
    bne.s   Wait3       ;Done? Else continue.

;*** End program ***

;Restore old Copper list

    move.l  #GRname,a1  ;Get parameter for OpenLibrary
    clr.l   d0
    jsr OpenLibrary(a6) ;Graphics Library open
    move.l  d0,a4       ;Address of GrahpicsBase to a4
    move.l  StartList(a4),COP1LC(a5) ;Load address of Startlist
    clr.w   COPJMP1(a5)
    move.w  #$83E0,DMACON(a5)   ; All DMA on
    jsr Permit(a6)      ;Task-Switching on

;Free memory of Copperlist
    move.l  CLadr,a1    ;Set parameter for FreeMem
    moveq   #CLsize,d0
    jsr FreeMem(a6) ;Memory freed

;Free memory of bitplane
    move.l  BPMemoryPtr,a1  ;Set parameter for FreeMem
    move.l  #BPMemSize,d0
    jsr FreeMem(a6) ;Memory freed

Ende:
    clr.l   d0      ;Error flag erased
    rts         ;End program


BPMemSize   = ((320*256)/8) ; 320 across, 256 down, 8 bits per byte.

; Copperlist

CLstart:
        dc.w    BPL1PTH,$ffff   ;The program needs to put the BP MSW adr here.
        dc.w    BPL1PTL,$ffff   ;The program needs to put the BP LSW adr here.

    dc.w    COLOR00,$0000   ;Background color black
    dc.w    COLOR01,$0fff   ;Foreground color white
;   dc.w    $640f,$fffe ;On line 100 change to
;   dc.w    COLOR00,$0f00   ;BG = red
;   dc.w    COLOR01,$0000   ;FG = black
;   dc.w    $be0f,$fffe ;Line 190 to
;   dc.w    COLOR00,$0fb0   ;BG = gold
    dc.w    $ffff,$fffe ;Impossible position: End of copperlist

CLend:
CLsize = CLend-CLstart

; Variables
CLadr:
    dc.l    0

BPMemoryPtr:
        dc.l    0

GRname:
    dc.b    "graphics.library",0
    align   0,4


END
;End of program