[A83] Re: Running external ASM programs from within an ASM program...
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[A83] Re: Running external ASM programs from within an ASM program...
Multitasking is far from impossible on a Z80 calc. Check out TSE for an
example of task-switching (83+ shell) and I've written a multithreading
kernel for a 73 shell I'm working on. The major problem for true
multitasking is running the programs back and forth. Obviously using
_insertmem and _delmem to swap out programs would be extremely slow, and not
even worth trying. So clearly, you must have all programs loaded already at
a time. What would work good is to have relocatable programs (via editing
absolute references) which was mentioned earlier on the list. You then could
switch between them in an interrupt routine. The 83+ LCD driver makes
saving/restoring the screen slow though. What I've specifically been working
on is probably the most useful type for a calc, where programs can create
threads which are called by the process managing interrupt in a circular
sequence. Thus the program has a main part that always executes, with
subroutines being called every interrupt.
Michael Vincent
Detached Solutions - www.detacheds.com
Radical Software - www.radicalsoft.org
----- Original Message -----
From: "Patai Gergely" <patai.ti@freemail.hu>
To: <assembly-83@lists.ticalc.org>
Sent: Tuesday, December 18, 2001 10:34 AM
Subject: [A83] Re: Running external ASM programs from within an ASM
program...
>
> > Yeah, memory protection is nifty and should be in any
> decent os,
> > but it is not something you _must_ have to call it an os.
> But that OS should not be called linux. :)
>
> Of course this was a joke, since even multitasking
> is impossible on these calcs, unless we restrict
> our programs. It would be kind of an extended Basic
> shell at the end.
>
> PG
>
>
>
>
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