[A83] Re: Official H**s Replacement Commands (OT)
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[A83] Re: Official H**s Replacement Commands (OT)
Can you also get *more* than the official labelling (with zero termination)?
It would be very, very, very nasty to load a large piece of the vat, and
cleared the whole lot.
>To clarify a bit, what he's saying is that >> 8 and & 255 are used to get
the 8-bit pieces of a 16-bit address. For example, when you do:
> ld hl,plotsscreen
>What you're doing is equivalent to
> ld h,plotsscreen >> 8 ;upper byte
> ld l,plotsscreen & 255 ;lower byte
>
>Thus you can use >> 8 and & 255 to just get one piece of the address if you
don't want to do an entire 16-bit load.
>
>
>In a message dated Tue, 3 Jul 2001 3:35:01 PM Eastern Daylight Time, "Kirk
Meyer" <kirk.meyer@colorado.edu> writes:
>
><<
>>> 8 shifts right 8 (get upper byte)
>& 255 ands with 255 (get lower byte)
>
>In this code it's obviously a joke, but >> 8 is often used for optimizing
>tables by splitting them across 256 bytes.
>
>-----Original Message-----
>From: assembly-83-bounce@lists.ticalc.org
>[mailto:assembly-83-bounce@lists.ticalc.org]On Behalf Of Jeff Ruud
>Sent: Tuesday, July 03, 2001 1:24 PM
>To: assembly-83@lists.ticalc.org
>Subject: [A83] Re: Official H**s Replacement Commands (OT)
>
>
>
>What are the >> and & in those lines for?
> ld a,plotsscreen >> 8
> ld a,plotsscreen & 255
>
>
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