Re: A83: a question
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Re: A83: a question
On Sat, 10 Jul 1999 16:25:18 EDT, you wrote:
>
>
>In a message dated 7/10/99 3:16:41 PM Central Daylight Time,
>bomber912@hotmail.com writes:
>
> > Hi everybody ...
> >
> > I have a question and it is really freacing me out
> >
> > There is a place in my prog that generates an ERR : Overflow...
> >
> > it looks like this :
> >
> > I have xy coordinates in bc
> >
> > push bc
> > couple of things that screw with registers
> > pop bc
> >
> > ;now i want to display the value of my x and y coordinates at 5,5 and
>5,9
> >
> > push bc
> > ld hl,0505h
> > ld (PENCOL),hl
> > ld a,b
> > call _SETXXOP1
> > call _DISPOP1A
> >
> > pop bc
> > ld hl,0905h
> > ld (PENCOL),hl
> > ld a,c
> > call _SETXXOP1
> > call _DISPOP1A
> >
> >
> > and it does the overflow error ... now is there something I'm not
>seeing
> > here or is it a logic problem
> >
> > thanks for any suggestions
> >
> > homonerdicus
> >
> > "summer is here, bring on the beer"
>
>Do a "call _zeroop1" before each of your "call _setxxop1" commands, because
>that command wont set all of OP1 to what A is, just the first byte, so
>there
>could be crap in the rest of OP1 which is why _DispOP1a cant handle it.
>Btw,
>you have to put the value into A of how many characters you want to
>display,
>that also may be causing th overflow error. cya...
>
>Jason_K
Yes, the last one. Change it to this:
push bc
ld hl,0505h
ld (PENCOL),hl
ld a,b
call _SETXXOP1
Here: ld a,2 ; load into A the maximum number of
characters to be displayed
call _DISPOP1A
pop bc
ld hl,0905h
ld (PENCOL),hl
ld a,c
call _SETXXOP1
ld a,2
call _DISPOP1A
I hope this helps.
James Vernon
jimbob_v@hotmail.com
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