43 lines
713 B
Plaintext
43 lines
713 B
Plaintext
( pixels )
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:dev/r fff8 ( std read port )
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:dev/w fff9 ( std write port )
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;x 2 ;y 2 ;color 1 ;alive 1
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|0100 @RESET
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#01 =dev/w ( set dev/write to screen )
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#01 =color ( set color )
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#0020 =x #0030 =y ( set origin )
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#01 =alive ( set alive = true )
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BRK
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|c000 @FRAME
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~alive #00 EQU BRK?
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#01 ~color ~x ~y ,putpixel JSR
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,move JSR
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BRK
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@move
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~x #0001 ADD2 =x ( incr x )
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~x #0040 LTH2 RTS? ( if x > 60 )
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#0020 =x ( x = 0x0020 )
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~y #0001 ADD2 =y ( incr y )
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~y #0050 LTH2 RTS? ( y > 50 )
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#00 ,alive STR ( alive = 0 )
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RTS
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@putpixel
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IOW2 ( y short )
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IOW2 ( x short )
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IOW ( color byte )
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IOW ( redraw byte )
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RTS
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|d000 @ERROR BRK
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|FFFA .RESET .FRAME .ERROR
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