2015-11-17 14:14:15 +00:00
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;
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; Clear (erase) the screen.
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;
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; Support the full 128- x 64-tile background.
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;
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2015-10-02 14:50:22 +00:00
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.export _clrscr
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.import plot
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2014-11-29 13:18:48 +00:00
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2015-08-29 13:58:57 +00:00
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.include "pce.inc"
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2015-09-19 13:37:39 +00:00
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.include "extzp.inc"
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2014-11-29 13:18:48 +00:00
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_clrscr:
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2015-08-29 13:58:57 +00:00
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st0 #VDC_MAWR
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st1 #<$0000
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st2 #>$0000
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2014-11-29 13:18:48 +00:00
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2015-08-29 13:58:57 +00:00
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st0 #VDC_VWR
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ldy #$40
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rowloop:
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ldx #$80
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colloop:
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2015-11-17 14:14:15 +00:00
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lda #' ' ; low byte of char. index
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2015-09-29 16:39:58 +00:00
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sta VDC_DATA_LO
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2015-11-17 14:14:15 +00:00
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lda #$02 ; background color, high nybble of char. index
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2015-09-29 16:39:58 +00:00
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sta VDC_DATA_HI
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2014-11-29 13:18:48 +00:00
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2015-08-29 13:58:57 +00:00
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dex
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bne colloop
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dey
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bne rowloop
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2014-11-29 13:18:48 +00:00
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2015-09-19 13:37:39 +00:00
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; Go to the home position.
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stz CURS_X
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stz CURS_Y
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2015-09-20 10:18:41 +00:00
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jmp plot
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2014-11-29 13:18:48 +00:00
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2015-07-13 10:10:09 +00:00
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;-------------------------------------------------------------------------------
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; force the init constructor to be imported
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.import initconio
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2015-08-29 13:58:57 +00:00
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conio_init = initconio
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