; Lezione15h.s		- Esempio degli effetti del BPLCON4 nella palette

	SECTION	AgaRulez,CODE

;	Include	"DaWorkBench.s"	; togliere il ; prima di salvare con "WO"

*****************************************************************************
	include	"startup2.s"	; Salva Copperlist Etc.
*****************************************************************************

		;5432109876543210
DMASET	EQU	%1000001110000000	; copper, bitplane DMA

WaitDisk	EQU	30	; 50-150 al salvataggio (secondo i casi)

START:

;	Puntiamo la pic AGA

	MOVE.L	#PICTURE,d0
	LEA	BPLPOINTERS,A1	
	MOVEQ	#8-1,D7			;num of bitplanes -1
POINTB:
	move.w	d0,6(a1)		
	swap	d0			
	move.w	d0,2(a1)		
	swap	d0			
	addi.l	#10240,d0		;lenght of bitplane
	addq.w	#8,a1
	dbra	d7,POINTB		;Rifai D1 volte (D1=num of bitplanes)

	bsr.s	MettiColori

	MOVE.W	#DMASET,$96(a5)		; DMACON - abilita bitplane, copper
	move.l	#CopList,$80(a5)	; Puntiamo la nostra COP
	move.w	d0,$88(a5)		; Facciamo partire la COP
	move.w	#0,$1fc(a5)		; Fmode azzerato, burst normale
	move.w	#$c00,$106(a5)		; BPLCON3 resettato
	move.w	#$11,$10c(a5)		; BPLCON4 resettato

LOOP:
	MOVE.L	#$1ff00,d1	; bit per la selezione tramite AND
	MOVE.L	#$11000,d2	; linea da aspettare = $110
Waity1:
	MOVE.L	4(A5),D0	; VPOSR e VHPOSR - $dff004/$dff006
	ANDI.L	D1,D0		; Seleziona solo i bit della pos. verticale
	CMPI.L	D2,D0		; aspetta la linea $110
	BNE.S	Waity1

Aspetta:
	MOVE.L	4(A5),D0	; VPOSR e VHPOSR - $dff004/$dff006
	ANDI.L	D1,D0		; Seleziona solo i bit della pos. verticale
	CMPI.L	D2,D0		; aspetta la linea $110
	BEQ.S	Aspetta

	bsr.s	CambiaCon4

	BTST	#6,$BFE001
	BNE.S	LOOP
	RTS

CambiaCon4:
	addq.b	#1,ContaSpetta
	cmp.b	#20,ContaSpetta	; Passati 20 frames?
	bne.s	NonAncora	
	clr.b	ContaSpetta	; resetta il "timer"
	addq.b	#1,MioCon4	; Cambia il byte alto di bplcon4
NonAncora:
	rts

ContaSpetta:
	dc.w	0

MettiColori:
	LEA	PICTURE+(10240*8),A0	; indirizzo della color palette alla
					; fine della figura -> in A0
	LEA	COLP0+2,A1		; Indirizzo del primo registro
					; settato per i nibble ALTI
	LEA	COLP0B+2,A2		; Indirizzo del primo registro
					; settato per i nibble BASSI
	MOVEQ	#8-1,d7			; 8 banchi da 32 registri ciascuno
ConvertiPaletteBank:
	moveq	#0,d0
	moveq	#0,d2
	moveq	#0,d3
	moveq	#32-1,d6	; 32 registri colore per banco

DaLongARegistri:	; loop che trasforma i colori $00RrGgBb.l nelle 2
			; word $0RGB, $0rgb adatte ai registri copper.

; Conversione dei nibble bassi da $00RgGgBb (long) al colore aga $0rgb (word)

	MOVE.B	1(A0),(a2)	; Byte alto del colore $00Rr0000 copiato
				; nel registro cop per nibble bassi
	ANDI.B	#%00001111,(a2) ; Seleziona solo il nibble BASSO ($0r)
	move.b	2(a0),d2	; Prendi il byte $0000Gg00 dal colore a 24bit
	lsl.b	#4,d2		; Sposta a sinistra di 4 bit il nibble basso
				; del GREEN, "trasformandolo" in nibble alto
				; di del byte basso di D2 ($g0)
	move.b	3(a0),d3	; Prendi il byte $000000Bb dal colore a 24bit
	ANDI.B	#%00001111,d3	; Seleziona solo il nibble BASSO ($0b)
	or.b	d2,d3		; "FONDI" i nibble bassi di green e blu...
	move.b	d3,1(a2)	; Formando il byte basso finale $gb da mettere
				; nel registro colore, dopo il byte $0r, per
				; formare la word $0rgb dei nibble bassi

; Conversione dei nibble alti da $00RgGgBb (long) al colore aga $0RGB (word)

	MOVE.B	1(A0),d0	; Byte alto del colore $00Rr0000 in d0
	ANDI.B	#%11110000,d0	; Seleziona solo il nibble ALTO ($R0)
	lsr.b	#4,d0		; Shifta a destra di 4 bit il nibble, in modo
				; che diventi il nibble basso del byte ($0R)
	move.b	d0,(a1)		; Copia il byte alto $0R nel color register
	move.b	2(a0),d2	; Prendi il byte $0000Gg00 dal colore a 24bit
	ANDI.B	#%11110000,d2	; Seleziona solo il nibble ALTO ($G0)
	move.b	3(a0),d3	; Prendi il byte $000000Bb dal colore a 24 bit
	ANDI.B	#%11110000,d3	; Seleziona solo il nibble ALTO ($B0)
	lsr.b	#4,d3		; Shiftalo di 4 bit a destra trasformandolo in
				; nibble basso del byte basso di d3 ($0B)
	ori.b	d2,d3		; Fondi i nibble alti di green e blu ($G0+$0B)
	move.b	d3,1(a1)	; Formando il byte basso finale $GB da mettere
				; nel registro colore, dopo il byte $0R, per
				; formare la word $0RGB dei nibble alti.

	addq.w	#4,a0		; Saltiamo al prossimo colore .l della palette
				; attaccata in fondo alla pic
	addq.w	#4,a1		; Saltiamo al prossimo registro colore per i
				; nibble ALTI in Copperlist
	addq.w	#4,a2		; Saltiamo al prossimo registro colore per i
				; nibble BASSI in Copperlist

	dbra	d6,DaLongARegistri

	add.w	#(128+8),a1	; salta i registri colore + il dc.w $106,xxx
				; dei nibble ALTI
	add.w	#(128+8),a2	; salta i registri colore + il dc.w $106,xxx
				; dei nibble BASSI

	dbra	d7,ConvertiPaletteBank	; Converte un banco da 32 colori per
	rts				; loop. 8 loop per i 256 colori.


;*****************************************************************************
;*				COPPERLIST				     *
;*****************************************************************************

	CNOP	0,8	; Allineo a 64 bit

	section	coppera,data_C

COPLIST:
	dc.w	$8E,$2c81	; DiwStrt
	dc.w	$90,$2cc1	; DiwStop
	dc.w	$92,$0038	; DdfStart
	dc.w	$94,$00d0	; DdfStop
	dc.w	$102,0		; BplCon1
	dc.w	$104,0		; BplCon2
	dc.w	$108,0		; Bpl1Mod
	dc.w	$10a,0		; Bpl2Mod
	dc.w	$10c		; BplCon4
MioCon4:
	dc.w	0

		    ; 5432109876543210
	dc.w	$100,%0000001000010001	; 8 bitplane LOWRES 320x256. Per
					; settare 8 planes setto il bit 4 e
					; azzero i bit 12,13,14. Il bit 0 e'
					; settato dato che abilita molte
					; funzioni AGA che vedremo dopo.

	dc.w	$1fc,0		; Burst mode azzerato (per ora!)

BPLPOINTERS:
	dc.w $e0,0,$e2,0	; primo 	bitplane
	dc.w $e4,0,$e6,0	; secondo	   "
	dc.w $e8,0,$ea,0	; terzo		   "
	dc.w $ec,0,$ee,0	; quarto	   "
	dc.w $f0,0,$f2,0	; quinto	   "
	dc.w $f4,0,$f6,0	; sesto		   "
	dc.w $f8,0,$fA,0	; settimo	   "
	dc.w $fC,0,$fE,0	; ottavo	   "

; In questo caso la palette viene aggiornata da una routine, per cui basta
; lasciare azzerati i valori dei registri.

	DC.W	$106,$c00	; SELEZIONA PALETTE 0 (0-31), NIBBLE ALTI
COLP0:
	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$e00	; SELEZIONA PALETTE 0 (0-31), NIBBLE BASSI
COLP0B:
	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$2C00	; SELEZIONA PALETTE 1 (32-63), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$2E00	; SELEZIONA PALETTE 1 (32-63), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$4C00	; SELEZIONA PALETTE 2 (64-95), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$4E00	; SELEZIONA PALETTE 2 (64-95), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$6C00	; SELEZIONA PALETTE 3 (96-127), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$6E00	; SELEZIONA PALETTE 3 (96-127), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$8C00	; SELEZIONA PALETTE 4 (128-159), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$8E00	; SELEZIONA PALETTE 4 (128-159), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$AC00	; SELEZIONA PALETTE 5 (160-191), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$AE00	; SELEZIONA PALETTE 5 (160-191), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$CC00	; SELEZIONA PALETTE 6 (192-223), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$CE00	; SELEZIONA PALETTE 6 (192-223), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$EC00	; SELEZIONA PALETTE 7 (224-255), NIBBLE ALTI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	DC.W	$106,$EE00	; SELEZIONA PALETTE 7 (224-255), NIBBLE BASSI

	DC.W	$180,0,$182,0,$184,0,$186,0,$188,0,$18A,0,$18C,0,$18E,0
	DC.W	$190,0,$192,0,$194,0,$196,0,$198,0,$19A,0,$19C,0,$19E,0
	DC.W	$1A0,0,$1A2,0,$1A4,0,$1A6,0,$1A8,0,$1AA,0,$1AC,0,$1AE,0
	DC.W	$1B0,0,$1B2,0,$1B4,0,$1B6,0,$1B8,0,$1BA,0,$1BC,0,$1BE,0

	dc.w	$FFFF,$FFFE	; Fine della copperlist

;******************************************************************************

; Figura RAW ad 8 bitplanes, cioe' a 256 colori

	CNOP	0,8	; allineo a 64 bit

PICTURE:
	INCBIN	"MURALE320*256*256c.RAW"

	end

Questo esempio non e' certo "bello", ma rende l'idea del funzionamento del
registro, che e' certamente utile in certe routines che potreste fare,
appositamente studiate per cambiare la palette.... potreste per esempio
mettere un $10c ogni linea per cambiare la palette in modo diverso molte
volte... per fare chissacche'....