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2015-02-19 14:35

awsm

Registered: Feb 2015
Posts: 13

Moving koala to different address (n00b)

I'm having a hard time understanding why this doesn't work for me:

The code below loads a koala file to $2000. All fine.
But in combination with music (starting at $1000) I get the music messed up. I figured that the pic overwrites parts of the music (>4096 bytes). Any other starting address than $2000 fails however, showing just garbage (updated $d018 too, but it didn't do the trick).

PICTURE 		= $2000
VIDEO 			= PICTURE+$1f40 
COLOR 			= PICTURE+$2328 
BACKGROUND 		= PICTURE+$2710 

* = PICTURE
!binary "resources/mypic.kla",,2 

* = $c000

init_koala	 
			
			sei
			lda #$00 
			sta $d020 ; Border Color 
			lda BACKGROUND 
			sta $d021 ; Screen Color 

			; Transfer Video and Color 
			ldx #$00 

			; Transfers video data 
vloop	       	lda VIDEO,x 
			sta $0400,x 
			lda VIDEO+$100,x 
			sta $0500,x 
			lda VIDEO+$200,x 
			sta $0600,x 
			lda VIDEO+$2e8,x 
			sta $06e8,x 
			; Transfers color data 
			lda COLOR,x 
			sta $d800,x 
			lda COLOR+$100,x 
			sta $d900,x 
			lda COLOR+$200,x 
			sta $da00,x 
			lda COLOR+$2e8,x 
			sta $dae8,x 
			inx 
			bne vloop 
			; 
			; Bitmap Mode On 
			; 
			lda #$3b 
			sta $d011 
			; 
			; MultiColor On 
			; 
			lda #$d8 
			sta $d016 

			; When bitmap adress is $2000
			; Screen at $0400 
			; Value of $d018 is $18
			lda #$18
			sta $d018 

          	        jmp *

... 11 posts hidden. Click here to view all posts....

2015-02-19 22:17

SIDWAVE
Account closed

Registered: Apr 2002
Posts: 2238

addition:

you must also poke d018 with charrom address.
do it this way:

so, when the koala is in $6000
here is to make d018 poke:

selectchar

lda $d018
and #240
ora #0 ;0-2-4-6-8-10-12-14 : 0000-07ff, 0800-0fff, 1000-17ff, 1800-1fff
; 2000-27ff, 2800-2fff, 3000-37ff, 3800-3fff
sta $d018

so, change the ORA
charbank 2 starts at $4000
so the ora must be 0

if the char of the koala is in 4800,
then it must be 2

each 0800 hop = +2 on the ORA

2015-02-20 13:02

awsm

Registered: Feb 2015
Posts: 13

@SIDwave

I think I'm almost there. The bank switching happens, the music plays fine along with the image and so on. But I still must oversee something trivial, as the bitmap displays, but color seems to be off: http://i.imgur.com/DcPzQdl.png


PIC_ADD     = $4000

* = $6000
!binary "resources/mypic.kla",,2 



init_koala	 
			
			;put this inside irq if used, else just do it
            ;KOALA PIC 2000
            lda $dd00 
            and #%11111100
            ora #%00000010 ;vic bank 3 (they go 3-2-1-0, so $6000 is #2)
            sta $dd00
            lda $d016
            ora #$10
            sta $d016
            LDA #$19
            STA $D018
            lda #$3b
            sta $d011

			ldx #$00 


			KOALARE
			lda $3f40+PIC_ADD,x ;add +$4000 on these to setup for $6000
			sta $0400,x
			lda $4040+PIC_ADD,x
			sta $0500,x
			lda $4140+PIC_ADD,x
			sta $0600,x
			lda $4228+PIC_ADD,x
			sta $06e8,x

			lda $4328+PIC_ADD,x ;add +$4000 for these to setup at $6000
			sta $d800,x
			lda $4428+PIC_ADD,x
			sta $d900,x
			lda $4528+PIC_ADD,x
			sta $da00,x
			lda $4610+PIC_ADD,x
			sta $dae8,x
			dex
			bne KOALARE

			lda $4710+PIC_ADD
			sta $d021
			
			; 
			; Bitmap Mode On 
			; 
			lda #$3b 
			sta $d011 

			; 
			; MultiColor On 
			; 
			lda #$d8 
			sta $d016 


			lda $d018
			and #240
			ora #8	;0-2-4-6-8-10-12-14 : 0000-07ff, 0800-0fff, 1000-17ff, 1800-1fff
			;	2000-27ff, 2800-2fff, 3000-37ff, 3800-3fff
			sta $d018

          	rts

2015-02-20 13:15

Bamse

Registered: Apr 2013
Posts: 7

Looks like you are still copying the "screen"-data to $0400. But since you switched the vic-bank this isn´t your screen anymore. Try copying to $4400,$4500... in your vloop.

2015-02-20 13:31

awsm

Registered: Feb 2015
Posts: 13

@Bamse: Hm. Are you looking at the code in the first post or the one from the last? Because I can't see where I'm copying to 0400 etc. anymore. Thank you!

2015-02-20 13:36

iAN CooG

Registered: May 2002
Posts: 3193

sta $0400,x <-

2015-02-20 13:40

awsm

Registered: Feb 2015
Posts: 13

I'm an idiot. Plus, it works now. But mainly idiot. :D
Thanks guys!

2015-02-20 13:52

Oswald

Registered: Apr 2002
Posts: 5094

no you're not, I remember how confusing this could be even when I wasnt a beginner.

2015-02-20 14:26

The Phantom

Registered: Jan 2004
Posts: 360

ldx #$00
wrap
lda $3f40,x
sta $0400,x
lda $4040,x
sta $0500,x
lda $4140,x
sta $0600,x
lda $4240,x
sta $0700,x

lda $4338,x
sta $d800,x
lda $4438,x
sta $d900,x
lda #4538,x
sta $da00,x
lda $4638,x
sta $db00,x
inx
bne wrap

lda #$18
ldx #$f8
ldy #$3b
sta $d018
stx $d016
sty $d011

rts

That's how I display koala/ocp from $2000-$4720. A koala from $6000-$8720 can be loaded into memory at $2000 and use the same code.
To display a koala where it stands in memory, from $6000 requires bank switching, which I don't have time to do at this moment, but that's not what you wanted to do ;)
I think $471e and $471f are bits for $d020 and $d021, not sure as I never use them :D
Doing it my way will also require any sprite inits to take place AFTER, since we write to $7f8-$7ff

2015-02-20 21:06

Ejner

Registered: Oct 2012
Posts: 43

Hey, just a small note about memory and graphics if you missed it...

When the VIC chip looks at $1000-$1fff and also $9000-$9fff, regardless of the data you have here, the VIC chip will see a mirror of the ROM charset. So no bitmap, fonts or screen color data can be displayed from these addresses...

Meaning, no FULLSCREEN bitmap in $0000 or $8000. Use instead $2000,$4000,$6000,$a000,$c000,$e000.

2015-02-20 21:08

awsm

Registered: Feb 2015
Posts: 13

Got it Ejner, thank you for the heads up!

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