Re: A83: Grbuf again


[Prev][Next][Index][Thread]

Re: A83: Grbuf again




AHH... I am tired of people wasting 5 bytes! It is in the rom...
lcd_busy is in the include file!

Sebastiaan Roodenburg wrote:
> 
> Hi!
> 
> Q1:
> The LCDBusy is defined as:
> 
> #define         lcdbusy         delay-interrupt_start+$8484
> 
> so, the LCDbusy is an call to 'delay':
> 
> delay:          push    af                      ; produce small delay
> for lcd driver
>         inc     hl
>         dec     hl
>         pop     af
>         ret
> 
> But why a delay? because the TI's Z80 is faster than the LCD-driver: if
> you don't include a delay, the LCD get's overloaded and starts
> displaying junk (i think)...
> 
> So that's th delay thing...
> 
> Q2:
> depends on what type of code... some code works the first time, somtimes
> its a stupid bug and takes me 1 or just a few times to recompile and
> sometimes it's an hard one and takes me a few hours to find out what's
> wrong... and how to fix the bug...
> 
> Hope this helped!
> 
> grtx,
> 
> Sebastiaan Roodenburg
> sebastiaan@rimsystems.nl
> 
> > hey,
> >
> > A while back Jason_K, whom I thank, posted a routine that copies the
> > LCD to
> > the GBUF ...
> >
> > LCD_To_GBUF:  ; credits = Ian Graf
> >       ld hl, Plotsscreen
> >       ld a, $07
> >       call LCDBusy
> >       out ($10), a
> >       ld a, $80
> >       ld d, a
> >
> > Read_Loop1:
> >       call LCDBusy
> >       out ($10), a
> >       ld a, $20
> >       call LCDBusy
> >       out ($10), a
> >       call LCDBusy
> >       in a, ($11)
> >       ld bc,12*256+$11
> >
> > Read_Loop2:
> >       call LCDBusy
> >       INI
> >       jr nz, Read_Loop2
> >       inc d
> >       ld a,d
> >       cp $BF
> >       jr nz, Read_Loop1
> >       ld a, $05
> >       call LCDBusy
> >       out ($10), a
> >       ret
> >
> > I didn't look at it until today and I don't get what the lcdbusy
> > stands for
> > So I took the complete source of capture 83 by Ian Graf and, due to my
> >
> > no-knoledge-about-interrupts don't get it now either...
> >
> > Could someone explain it to me because the code is't commented
> > enough... (my
> > opinion) I have attached it ...
> > And is there another LCD to GBUF routine that someone could post ?
> >
> > thanks.
> >
> > Q2: For advanced programmers...
> > I was wondering, how many times do you have to correct some code you
> > write... I mean, to me it takes me 10 minutes to work up the logical
> > suite
> > and write the code and then at least 1 hour of debugging.  And after 1
> > hour
> > of work I always come here and ask you for help.... What about you
> > what
> > pourcentage of your time do you spend in debugging?
> >
> > About the unsubscription thing.... Yes it is possible to unsubscribe
> > someone
> > else, just read the infoletter you received when you joined this list
> > .... I
> > could post it if you don't have it ....
> > the fact that they haven't replied means that thay no longer have
> > acces to
> > the list.... until the next time they subscribe.
> >
> > thanks
> >
> >
> >
> >
> > ()()()()()()()()()()()()()()()()    ()()()()()()
> > () www.homonerdicus.cjb.net  ()    ()visit me()
> > ()()()()()()()()()()()()()()()    ()()()()()()
> >
> >
> > ______________________________________________________
> > Get Your Private, Free Email at http://www.hotmail.com
> >
> 
>   ------------------------------------------------------------------------
> 
>    Part 1.2    Type: application/ms-tnef
>            Encoding: base64

-- 
Scott "_Wrath_" Dial
wrath@calc.org
ICQ#3608935
TimeCity Co-Lead Developer, AI - www.timecity.org
Member of TCPA - tcpa.calc.org


Follow-Ups: References: