Re: A86: actual asm help


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Re: A86: actual asm help




sorry i noticed some errors there...that isn't how it is in the program...
basically what i need to know to trouble shoot this is

ld hl,_textshadow

ld a,1
ld (hl),a ......what does h contain...and what does l contain

ld a,(hl)
cp 1    ...........does a now contain 1

ld bc,$FC00
ld (hl),bc.......what does h contain and what does l contain

i really have trouble with keeping in my head what value is in each register
when a 8 bit register is loaded into a 16 bit register....do you have to
clear the upper or lower byte first like m68k asm ?

sorry for the earlier mix up







----- Original Message -----
From: Cassady Roop <croop@oregontrail.net>
To: <assembly-86@lists.ticalc.org>
Sent: Thursday, May 13, 1999 11:46 AM
Subject: Re: A86: actual asm help


>
> I'm not sure I understand your code right, but are you executing a RET
> in a routine that you jumped to?  If you are, that will do a nice job of
> screwing up the stack, and then when you try to do something like exit
> the program it will crash.  Replace the JP to your char display routine
> with a CALL.
>
> Eugene Dirks wrote:
> > _freemem points to some free mem
> >
> >     ld hl,_freemem
> >     ld a,1
> >     ld (hl),a
> >     inc hl
> >     ld (hl),a
> >
> >     dec hl
> >     dec hl
> >     ld a,(hl)
> >     jp "a routine to display the correct character that i'm pretty sure
> > works
> >                 it... for example... cp 1
> >                                                jp z,put_1
> >                                                ....then it does a "ret"
>
> don't RET from a jump
>
> >     inc hl
> >     ld a,(hl)
> >     jp "the same char display routine"
> >
> > this always freezes up the calc.  I don't see it, but is there something
> > wrong with the above code that doesn't look right?  if not then it's in
my
> > char_put routine...
> >
> > thanks for any help you can give
> >
> > billybobIV
> > chad@dirks.com
> > http://chad.dirks.com
>
>




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