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Flavioweb
Registered: Nov 2011
Posts: 447 |
$D3 behavior: values over $27. Why?
Take this code:
.> c000 a9 ff lda #$ff
.> c002 8d 13 c0 sta $c013
.> c005 a9 20 lda #$20
.> c007 ce 13 c0 dec $c013
.> c00a f0 06 beq $c012
.> c00c 20 d2 ff jsr $ffd2
.> c00f 4c 05 c0 jmp $c005
.> c012 60 rts
set a breakpoint to $c00c.
Check $D3 for current cursor column.
Why there are values over $27 ?
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MagerValp
Registered: Dec 2001
Posts: 1059 |
Because there are 80 characters in a line. |
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Skate
Registered: Jul 2003
Posts: 491 |
i tried it and $d3's value is zero here. and cartridges or other routines involved at your test platform? |
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Wisdom
Registered: Dec 2001
Posts: 90 |
The number of characters in a logical line can be either 40 or 80. Check $00D5 for current logical line length. |
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Flavioweb
Registered: Nov 2011
Posts: 447 |
There is a way to set virtual line lenght always to $27?
Setting $D5 also after PLOT call seems don't work.
Something related to screen area hi bytes in $D9-$F1? |
