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Re: Screen Scrolling

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"duhas...@gmail.com" <duhast6377@gmail.com> writes:

> On Monday, May 9, 2022 at 6:40:09 PM UTC-4, Brian Patrie wrote:
>> Kent Dickey wrote: 
>> > In article <f812d193-6a9e-4bfa...@googlegroups.com>, 
>> > qkumba  wrote: 
>> >> HLINE and VLINE don't scroll. 
>> > 
>> > To give a little more detail, try the following: 
>> > 
>> > 10 FOR I = 0 TO 23 
>> > 20 COLOR= 3 
>> > 30 HLIN 0,39 AT I * 2 
>> > 40 COLOR= 10 
>> > 50 HLIN 0,39 AT I * 2 + 1 
>> > 60 NEXT 
>> > 70 FOR I = 1 TO 10000000 
>> > 80 NEXT 
>> > 
>> > The HLIN (and VLIN and PLOT) commands work on the text screen, 
>> > if you don't give GR.
>> Better yet, write directly to the colour mask byte: 
>> 
>> 10 FOR I = 0 TO 47 
>> 20 POKE 48,163
>> 30 HLIN 0,39 AT I
>> 40 NEXT 
>> 90 ON PEEK(49152) < 128 GOTO 90 : POKE 49168,. 
>> 
>> (That last line just waits for a key, and clears it.) 
>> 
>> Or (on a machine with MouseText): 
>> 
>> 10 PRINT CHR$(17); : POKE 49167,. : TEXT 
>> 21 FOR X = 0 TO 38 STEP 2 
>> 22 POKE 48,86 : VLIN 0,47 AT X 
>> 23 POKE 48,87 : VLIN 0,47 AT X + 1 
>> 24 NEXT 
>> 90 ON PEEK(49152) < 128 GOTO 90 : POKE 49168,. 
>> 
>> (Line 10 ensures 40 columns, alt charset, text mode.)
>
> Ok I tried the BASIC versions and they work like I want, but I tried to right a little
> assembly program to test it and I can't get it to work.
>
>       
> *300L                                   
> 0300-   A9 A3       LDA   #$A3       ;Load "#"   
> 0302-   85 30       STA   $30           ;Stick in color
> 0304-   A9 27       LDA   #$27         ;Load rightmost 
> 0306-   85 2C       STA   $2C           ;Stick in 2C
> 0308-   A9 09       LDA   #$09          ;Load vertical coord
> 030A-   A0 00       LDY   #$00          ;load horizontal coord
> 030C-   20 19 F8    JSR   $F819      ; call HLIN
>
> Should have a line of # through the screen and I don;t....
>  
> 0        
> *                                       

You still have to draw two HLINs because with one you're only setting
one half of the byte (the top or the bottom, depending on your
Y-coordinate).


-- 
--
Jerry     jerry+a2 at jpen.ca

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Screen Scrolling "duhas...@gmail.com" <duhast6377@gmail.com> - 2022-05-06 20:38 -0700
  Re: Screen Scrolling barrym95838 <barrym95838@yahoo.com> - 2022-05-07 01:46 -0700
    Re: Screen Scrolling qkumba <peter.ferrie@gmail.com> - 2022-05-07 12:39 -0700
      Re: Screen Scrolling barrym95838 <barrym95838@yahoo.com> - 2022-05-08 01:24 -0700
      Re: Screen Scrolling kegs@provalid.com (Kent Dickey) - 2022-05-09 04:03 +0000
        Re: Screen Scrolling qkumba <peter.ferrie@gmail.com> - 2022-05-09 09:41 -0700
          Re: Screen Scrolling Brian Patrie <bpatrie@bellsouth.spamisicky.net> - 2022-05-09 17:51 -0500
            Re: Screen Scrolling Brian Patrie <bpatrie@bellsouth.spamisicky.net> - 2022-05-13 02:15 -0500
        Re: Screen Scrolling qkumba <peter.ferrie@gmail.com> - 2022-05-09 09:42 -0700
        Re: Screen Scrolling Brian Patrie <bpatrie@bellsouth.spamisicky.net> - 2022-05-09 17:40 -0500
          Re: Screen Scrolling "duhas...@gmail.com" <duhast6377@gmail.com> - 2022-05-10 18:55 -0700
            Re: Screen Scrolling Jerry Penner <jerry+a2@jpen.ca> - 2022-05-10 21:57 -0600
              Re: Screen Scrolling Oliver Schmidt <ol.sc@web.de> - 2022-05-11 07:33 +0000
              Re: Screen Scrolling Brian Patrie <bpatrie@bellsouth.spamisicky.net> - 2022-05-13 02:33 -0500
  Re: Screen Scrolling I am Rob <gids.rs@sasktel.net> - 2022-05-07 14:22 -0700
  Re: Screen Scrolling Speccie <someone@somewhere.com> - 2022-05-08 07:55 +0100
  Re: Screen Scrolling mmphosis <mmphosis@macgui.com> - 2022-05-13 16:39 +0000

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