Re: A85: **RIGEL - the NEW shell**

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Re: A85: **RIGEL - the NEW shell**

Ben Sferrazza wrote:
> 
> [Rigel desc]
> 
> I just uploaded it to www.ticalc.org.  It may not be up as of now, but
> look for it Sept. 16 (Tuesday) for the full package.  Thank you.

I didn't find prgmexmp.txt and libexmp.txt - or were those replaced
with lessons.doc?

A few things that crossed my mind when I read the doc files (and some
disasm :) ):

In lessons.doc you say "All interrupts are removed by Rigel upon exiting
Rigel." Does this mean that interrupt won't be resident in TI-OS?

When you install an interrupt, you simply just puts the pointer
to the routine in the table (btw, the interrupt chain mode is identical
with usgard, although the routine to store/remove an interrupt is
different). If you want to install a TSR, I can't understand how
that pointer will change when the program changes memory location. What
I mean is that if program A installs a TSR, and then if you run progam
B,
program A has been moved and the pointer to the TSR must change, else
the
calc will crash. Or have I missed something here? (this is just theory -
I haven't tested anything).

Interesting idea to store the interrupt table at $8200-$8300, but won't
you
mess up with TI-OS later? I checked ti-ram.txt, but it didn't say much
about that
particular memory area. If you don't restored the contents after
quitting Rigel,
some parts of the TI OS must be corrupted. Using that method will
definately
guarantee that you never can run TSR programs in TI-OS.

I also noted that you move the stack - is this really necessary? I
didn't
really get what you were doing (storing something at a fixed location I
assume), but can't you just store it at $FA70 instead? I didn't check
this
to closely, so I may have missed something.

Another thing: HOW are you going to make Rigel backward compatible!?!?
According
to rigel.h, you move the program you want to run directly after Rigel.
If you
in a later version increase the Rigel size (if only with a few bytes),
you would
have to change prog_start, ie you would lose backward compatibility.

Also, do you update the VAT when relocating (I doubt it)? You know,
that's
not very good...

This were just some few things that popped up at the first look. Since I
haven't
tested it, some of my statements above may be wrong.

-- 
Jimmy Mårdell                "The nice thing about standards is that 
mailto:mja@algonet.se         there are so many of them to choose from."
http://www.algonet.se/~mja    
IRC: Yarin                   "Sanity? I'm sure I have it on tape
somewhere!"
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