A82: Re: Re: Fw: Proposed open operating system/gui/shell (CalcOS-82,83,

[Prev][Next][Index][Thread]

A82: Re: Re: Fw: Proposed open operating system/gui/shell (CalcOS-82,83,85,86)

From: Dines Justesen <c958362@student.dtu.dk>
To: assembly-82@lists.ticalc.org <assembly-82@lists.ticalc.org>;
rileym@geocities.com <rileym@geocities.com>; calc-ti@lists.ppp.ti.com
<calc-ti@lists.ppp.ti.com>
Date: Wednesday, 15 October, 1997 01:39
Subject: A82: Re: Fw: Proposed open operating system/gui/shell
(CalcOS-82,83,85,86)


>Libraries has been tried on the TI85 and the authors of the shell found out
>that it was a bad idea, and therefore they removed them from the shell.
>Libraries are nice for programmers because they make it easier for us, but
>most users do not like them. Th reason for this is that you need a lot of
>variables on your calc to run one program and that it is too complicated to
>remember which libs goes with which programs.
Well, users have to decide.  Do they want more programs (because libs make
it easier for programmers), smaller program size (because of lib sharing,
a.k.a. a greyscale graphics lib could be shared among 3 programs that use
greyscale graphics instead of having 3 copies of almost identical code) or,
do they want to have less variables on their calculator?  Seems to me, the
first two are what everyone keeps asking for (more progs, smaller size).

>Another thing you are suggesting is multitasking. You have to remember that
>this is a calc, with a small processor and a limited amount of ram. The
>question is do we need multitasking ? are we willing to use some of the RAM
>for a feature like this ? My answer is no.
I am not saying that it should be preemptive multithreaded multitasking!  I
just ment the ability to have multiple tasks (most likely, not more than 3)
to perform different parts of a program (message handler for windows-like
apps, or a keyboard handler for a game, things like that).  I didn't mean we
should have Windows 95 like multitasking!

>You say that you want the the OS to work on all calcs, but it seems like
you
>have not thought about (or do not know about) the problems with all this.
>One of the big problems is that not all functions found on one calc has
been
>found on the other. I am currently working on finding these functions on
>both the ti85 and the ti82, but it takes time. These problems would have to
>be solved before you can make your OS work with all the calcs, and since i
>am (as far as i know) the only one working on this it might take some time.
>So you would probably endup with a OS for the TI82 which could not be
ported
>to the other calcs with out chaning the rom calls, and then people would
>have to make seperate version of their program for each calc anyway.
There would be one copy of the OS for each calc (with the ROM calls for that
calc built-in).  Then, the programs would be portable (probably would need
to be put in different files for different calculators 82p, 83p, 85s, 86p)
but the programmer wouldn't have to go through and change nearly every line
in the code just to re-assemble for another calculator.  It would be nearly
the equivilant of different ROM versions, just the ROM versions are on
different types of calculators.  I mean, that is essentially the only
difference between the calcs (there are only minor differences in hardware).
The only big problem would be in deciding how to handle the different screen
size of the TI-85.

>You also write that you want your OS to be small. The OS you are writing
>includes more functions than Usgard and alot of people think that it is too
>big. So what makes you think that people will like your OS which is even
>bigger ? Again you have to remember that these calcs only have 32k of mem.
Ahh... another reason for libs.  The user (and programmer) can decide which
libs they will need for their programs and then load only those.  If a lib
is found to be only of limited use (or none at all), no programmers would
make programs that use them and no users would have them on their calcs (and
then, in the next version, we would probably remove them).

>As far as i can see you are missing some of the important features of a
>shell in your OS. First of all i think tha it s very important to support
as
>many rom versions as possible and i know of 3 which are not yet supported
by
>a shell. Besides that several rom calls which could be very useful has not
>been added in any shell yet because they lack documentation.
As of now, there are enough known ROM routines to do the basic things needed
to create a program (or else there wouldn't be any!) like drawing text,
creating pixels on the screen, etc.  As more advanced functions are found,
they can be added in libraries (i.e. a floating point library as the
floating point functions are more documented, or a variable library for
accessing variables, lists, etc.)

Thank you for your feedback (or flame whichever the case may be :-) ),

Riley McArdle
rileym@geocities.com
http://griffn.base.org/
Warning
Could not process part with given Content-Type: text/x-vcard; name="Riley McArdle (Public).vcf"