Writing a mini intro with picture and sid tune (C64) part 1

Last Updated or created 2023-08-02

Started with a example from https://codebase64.org/

But that didnĀ“t work (see movie clip)

looking at the sid info:

Title Bottom
Author Richard Bayliss
Released 2011 The New Dimension
Load Address $8000
Init Address $8000
Play Address $8003
Number of tunes 1
Default tune 1
Speed $00000000
SID Model 8580
Clock PAL
File Format PSID
Format Version 2
BASIC false
PlaySID Specific false

I saw that I have to move the load/init/play address.

Luckily there is sidreloc !

wget https://hd0.linusakesson.net/files/sidreloc-1.0.tgz
tar xzvf sidreloc*
cd sidreloc
make

Using:

~/Downloads/sidreloc-1.0/sidreloc  -p 10 ~/projects/sidplaybottomdemo/bottom.sid ~/projects/sidplaybottomdemo/bottom1000.sid

I could successfully move the sid to $1000

Final code (for now, next time i’ll add a picture).
(Using ACME as compiler, and X64 (vice as emulator))

;https://codebase64.org/doku.php?id=base:simple_irq_music_player
             !to "bottom.prg",cbm

        * = $0801
			
sysline:	
        !byte $0b,$08,$01,$00,$9e,$32,$30,$36,$31,$00,$00,$00 ;= SYS 2061

        * = $080d 

             sei
             lda #<irq
             ldx #>irq
             sta $314
             stx $315
             lda #$1b
             ldx #$00
             ldy #$7f 
             sta $d011
             stx $d012
             sty $dc0d
             lda #$01
             sta $d01a
             sta $d019 ; ACK any raster IRQs
             lda #$00
             jsr $1000 
             cli
hold         jmp hold 
                      ; we could also RTS here, when also changing $ea81 to $ea31
irq
             lda #$01
             sta $d019 ; ACK any raster IRQs
             jsr $1003 ;Play the music
             jmp $ea31
            
            * = $1000
             !binary "bottom1000.sid" ,, $7c+2

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