[A83] Re: call vs. bcall()

To: assembly-83@lists.ticalc.org
Subject: [A83] Re: call vs. bcall()
From: Tijl Coosemans <tijl@ulyssis.org>
Date: Tue, 24 Dec 2002 16:18:42 +0100
In-Reply-To: <F110VhyemYewQ1N8Pik00000380@hotmail.com>
References: <F110VhyemYewQ1N8Pik00000380@hotmail.com>
Reply-To: assembly-83@lists.ticalc.org

On Mon, 23 Dec 2002 17:25:47 +0000
"Pieter Van Nuffel [aka SUCKER]" <sucker_pvn@hotmail.com> wrote:

> When there is a part like this:
> 
>   ...
>   call _newline
>   ret
>   ...
> 
> It can be easily replaced by a single jump to _newline. But this is
> not so with the Ti-83+ bcall(). I do know bcall's are for rom page
> swapping, but what about it than?

bcall(xxxxh) becomes rst 28h \ .dw xxxxh. The call is necessary because
the routine at 0028h pops the return address from the stack to get the
pointer. Therefore jp 0028h \ .dw xxxxh wouldn't work. You always need a
call using this system. That's why bjump() is also defined as a call.
The name bjump() is somewhat confusing though. It isn't to jp what bcall
is to call.

References:

[A83] call vs. bcall()

From: "Pieter Van Nuffel [aka SUCKER]" <sucker_pvn@hotmail.com>