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@@ -0,0 +1,41 @@
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+*=$0800 "BASIC Start"
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+ // location to put a 1 line basic program so we can just
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+ // type run to execute the assembled program.
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+
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+ // will just call assembled program at correct location
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+ // 10 SYS (4096)
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+
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+ // These bytes are a one line basic program that will
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+ // do a sys call to assembly language portion of
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+ // of the program which will be at $1000 or 4096 decimal
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+ // basic line is:
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+ // 10 SYS (4096)
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+ .byte $00 // first byte of basic should be a zero
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+ .byte $0E, $08 // Forward address to next basic line
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+ .byte $0A, $00 // this will be line 10 ($0A)
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+ .byte $9E // basic token for SYS
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+ .byte $20, $28, $34, $30, $39, $36, $29 // ASCII for " (4096)"
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+ .byte $00, $00, $00 // end of basic program (addr $080E from above)
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+
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+*=$1000 "Main Start"
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+
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+ ldx #$00
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+ stx $d020 // Border color register
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+ stx $d021 // Background color
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+
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+clear: lda #$20 // spacebar screen code
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+ sta $0400,x // fill four areas of screen with 256 spacebar characters
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+ sta $0500,x
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+ sta $0600,x
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+ sta $06e8,x
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+ lda #$00 // set foreground to black in Color Ram
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+ sta $d800,x
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+ sta $d900,x
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+ sta $da00,x
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+ sta $dae8,x
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+ inx
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+ bne clear // bne = branch on not equal
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+ // did x turn to zero already?
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+ // if yes -> stop loop
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+ // if no -> continue loop
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+ rts
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