16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits 
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 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits

Old programs often used timing loops, but the new processors
can be too fast - so the timing loop calibration tries to divide by
zero.

Older Borland Turbo Pascal built EXEs are particularly prone to this --
several patches and fixes have been developed for them.  Start
with Timo Salmi's Pascal FAQ in comp.os.msdos.programmer
among many other places -- or just goto Garbo and find the
TP patches for Fast Pentium II's and III's.
--
Kevin G. Rhoads, Ph.D. (The Cheshire Cat for official Internet mascot.)



Fri, 13 Sep 2002 03:00:00 GMT  
 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits

I have EXE patcher and patched run-time library at my homepage in the
"General Programming" section.

So don't worry. :))

Alexei A. Frounze
--
Homepage: http://alexfru.chat.ru
Mirror:   http://members.xoom.com/alexfru

Quote:

> Old programs often used timing loops, but the new processors
> can be too fast - so the timing loop calibration tries to divide by
> zero.

> Older Borland Turbo Pascal built EXEs are particularly prone to this --
> several patches and fixes have been developed for them.  Start
> with Timo Salmi's Pascal FAQ in comp.os.msdos.programmer
> among many other places -- or just goto Garbo and find the
> TP patches for Fast Pentium II's and III's.
> --
> Kevin G. Rhoads, Ph.D. (The Cheshire Cat for official Internet mascot.)




Sat, 14 Sep 2002 03:00:00 GMT  
 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits


Quote:
>Old programs often used timing loops, but the new processors
>can be too fast - so the timing loop calibration tries to divide by
>zero.

Has that been some kind of a general problem?

Quote:
>Older Borland Turbo Pascal built EXEs are particularly prone to this --
>several patches and fixes have been developed for them.

Actually the older versions are not the problem. They do have a bug
that causes too short delays built that's it. The problem is the version
7.0 which was the last version released. It introduced a new delay
calibration routine to fix 7the above mentioned bug. It just had an even
worse bug in it: unchecked division.

One should always check that division is safe, that is if one divides by
BX, one does CMP DX,BX  JAE error.

Osmo



Sat, 14 Sep 2002 03:00:00 GMT  
 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits

Quote:
> Older Borland Turbo Pascal built EXEs are particularly prone to this --

Has anybody heard of similar problems with dos-based Watcom c/c++ programms
? I remember having division by zero appear all of a sudden with some
programs I had written when I switched to my new computer (450 Mhz versus
133)). Then again, my new computer has 96 megs of ram whereas the previous
one has 32 megs, which means I crossed the mystical 64 meg barrier... Well,
I switched to codewarrior anyway so this isn't too hot an issue :)


Sat, 14 Sep 2002 03:00:00 GMT  
 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits



Quote:


> >Old programs often used timing loops, but the new processors
> >can be too fast - so the timing loop calibration tries to divide by
> >zero.
[..]
> Actually the older versions are not the problem. They do have a bug
> that causes too short delays built that's it. The problem is the version
> 7.0 which was the last version released. It introduced a new delay
> calibration routine to fix 7the above mentioned bug. It just had an even
> worse bug in it: unchecked division.

Talking of timing loops, there was a thread a while back which
mentioned a particular "safe" i/o port to read or write, and
which offered a pretty constant delay regardless of CPU speed.

Does anybody remember which port that was, and what the delay
was?  I found reference to a "dummy delay" in Ralf Brown's list
for ports 0xEB and 0xED, but can't remember if one of these was
the port that was mentioned in the newsgroup.  And there was no
clue as to the actual delay.

I could use such a mechanism for a CPU-independent serial port
handler, and any help would be much appreciated.

Pete
--
Replies to the newsgroup, please: email from unknown sources
will likely bounce...



Sat, 14 Sep 2002 03:00:00 GMT  
 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits

Quote:

> one has 32 megs, which means I crossed the mystical 64 meg barrier... Well,
> I switched to codewarrior anyway so this isn't too hot an issue :)

how's codewarrior ? any cool stuff about it ?
i'm looking to switch compilers/dev tools.

--
Stephane Hockenhull
Rv[Beyond]



Thu, 19 Sep 2002 04:00:00 GMT  
 16 bits Dos EXE run problem / Problème d'execution d'un EXE Dos 16 bits



Quote:


> > one has 32 megs, which means I crossed the mystical 64 meg barrier...
Well,
> > I switched to codewarrior anyway so this isn't too hot an issue :)

> how's codewarrior ? any cool stuff about it ?
> i'm looking to switch compilers/dev tools.

> --
> Stephane Hockenhull
> Rv[Beyond]

The compiler seems quite OK to me. They seem to have dropped pascal-support
in V5.0, but if you can get academic edition, that still makes a C/C++
compiler for win32 and macos as well as a java developpment system for a
cheap price... You also have RAD support, *but* (and this was not stated
very clearly) only for java (javabeans, of course). MFC is of course
supported. The IDE is not very useful either, the editor supports syntax
coloring, but has an annoying bug (sometimes some text vanishes with no
reason at all and you have to scroll it out and in again to make it appear).
To put it in a nutshell, although the product is better integrated than GNU,
what you get is mainly a (good) compiler, but I have the feeling the
graphical tools are mere excuses against Microsoft VC++.


Sat, 21 Sep 2002 03:00:00 GMT  
 
 [ 7 post ] 

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