Re: A86: Bug in TI86EMU?

To: assembly-86@lists.ticalc.org
Subject: Re: A86: Bug in TI86EMU?
From: ComAsYuAre@aol.com
Date: Mon, 28 Sep 1998 21:27:44 EDT
Delivered-To: assembly-86-outgoing@towerguard.unix.edu.sollentuna.se
Reply-To: assembly-86@lists.ticalc.org


In a message dated 9/28/98 00:51:05 Eastern Daylight Time, electrum@tfs.net
writes:

> I think I found an unfortunate bug in TI86EMU, but I'm not sure.  The
>  instruction JP (HL) should jump to the address stored in the memory
>  location that HL points to, correct?  But in TI86EMU, it jumps to HL
>  instead.  It is not a bug with the assembler, because the emu disassembles
>  it properly as JP (HL).  It's probably not a bug, I'm just too tired, but
>  anyway...
>  
>  In an effort to work around it, I came up with this code:
>  
>   ld e,(hl)
>   inc hl
>   ld d,(hl)
>   ex de,hl
>   ld (DoMenuModify+1),hl
>  DoMenuModify:
>   jp 0
>  
>  I'm sure there is a much better solution, but I can't see it tonight.
>  Thanks for any help.


if you want to jump to any 16-bit value stored in a register, do this:

 push hl
 ret

 or whatever register has the address in it.  whenever a z80 hits a ret, it
pops the last value off the stack and jumps there