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Author Topic: WriteLn and DOSBox  (Read 19891 times)

MarkMLl

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Re: WriteLn and DOSBox
« Reply #15 on: June 21, 2021, 12:20:43 pm »
@MarkMLI

Can you tell us which dos version is installed on this laptop (Sony Miaow laptop) ?

Before installing GO32V2.

Erik

The latest FreeDOS. I messed around with various combinations using a scratch disk, but I think I ended up leaving it on a secondary partition of the live disk booted via GRUB hence one of the non-standard boot managers.

MarkMLl
MT+86 & Turbo Pascal v1 on CCP/M-86, multitasking with LAN & graphics in 128Kb.
Pet hate: people who boast about the size and sophistication of their computer.
GitHub repositories: https://github.com/MarkMLl?tab=repositories

lucamar

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Re: WriteLn and DOSBox
« Reply #16 on: June 21, 2021, 01:35:37 pm »
** The reason I was interested in looking at this was that I wanted to see how nicely FreeDOS played with other OSes etc. So far, I suspect that most of the problems I've seen were down to misinterpreted sector addresses, i.e. LBA vs non-LBA partition table entries, [...]

More problems than that gives trying to use a GPT partitioned vs. a traditional one, and since most hardware now comes GPT-partitioned ... Though I'm not quite as up-to-date as I used to be in FreeDOS; we just use v1.2 in old (or "make-up to look old") hardware when we need to install a new one; maybe the new 1.3 to-be is better in this respect.

Of course one solution, as you've discovered, is to use GRUB (or similar) to boot, though you might also find some problems with that in some configurations. That's probably one of the reason why most so-called "FreeDOS" (meaning "non-OS") computers actually have some kind of small Linux (like EndlessOS).

Quote
Leaving everything else aside, I can confirm that FPC 3.2.0 on Go32V2 running directly on i386 hardware (Sony Miaow laptop) renders all characters and character positions correctly, in particular the menu that you showed in your posting.

So I'd put my money on this being a problem in a library or BIOS facility used by multiple x86 emulators. ****

That's actually quite interesting ... and rather baffling, since the IDE has been working quite well till now and the only piece I can think of having to bear with this would be the Bosch (virtual) VGA BIOS, and that's a really mature and optimized piece of software. The other thing it might be would be the VGA emulation, but those are also rather mature and well understood. I would love to have the time to investigate this more fully, sounds interesting; unfortunately I haven't got it :(
Turbo Pascal 3 CP/M - Amstrad PCW 8256 (512 KB !!!) :P
Lazarus/FPC 2.0.8/3.0.4 & 2.0.12/3.2.0 - 32/64 bits on:
(K|L|X)Ubuntu 12..18, Windows XP, 7, 10 and various DOSes.

MarkMLl

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Re: WriteLn and DOSBox
« Reply #17 on: June 21, 2021, 04:44:00 pm »
More problems than that gives trying to use a GPT partitioned vs. a traditional one, and since most hardware now comes GPT-partitioned ... Though I'm not quite as up-to-date as I used to be in FreeDOS; we just use v1.2 in old (or "make-up to look old") hardware when we need to install a new one; maybe the new 1.3 to-be is better in this respect.

Well, this is specifically my "old OS" laptop: formatted using Windows XP and usually booting into Debian "Lenny". However, since setting that up I've discovered that I can run a Lenny image entirely happily under Docker, which I suspect would also obfuscate (render irrelevant due to its being inaccessible) things like the distinction between classic and GPT partitioning. And if Docker's won't play ball there's always Qemu, or at a pinch UML (although if hosted on 64-bit hardware it can't run a 32-bit kernel).

Quote
Of course one solution, as you've discovered, is to use GRUB (or similar) to boot, though you might also find some problems with that in some configurations. That's probably one of the reason why most so-called "FreeDOS" (meaning "non-OS") computers actually have some kind of small Linux (like EndlessOS).

I suspect that much of FreeDOS's compatibility with modern hardware is based on HP using it on a diagnostic partition.

Quote
Quote
Leaving everything else aside, I can confirm that FPC 3.2.0 on Go32V2 running directly on i386 hardware (Sony Miaow laptop) renders all characters and character positions correctly, in particular the menu that you showed in your posting.

So I'd put my money on this being a problem in a library or BIOS facility used by multiple x86 emulators. ****

That's actually quite interesting ... and rather baffling, since the IDE has been working quite well till now and the only piece I can think of having to bear with this would be the Bosch (virtual) VGA BIOS, and that's a really mature and optimized piece of software. The other thing it might be would be the VGA emulation, but those are also rather mature and well understood. I would love to have the time to investigate this more fully, sounds interesting; unfortunately I haven't got it :(

But as I've said before, the issue appeared to be whether the characters being displayed were strict-ANSI or extended. What's the saying... "When you have eliminated the impossible the remainder, however unlikely, must be the truth"? :-)

MarkMLl
MT+86 & Turbo Pascal v1 on CCP/M-86, multitasking with LAN & graphics in 128Kb.
Pet hate: people who boast about the size and sophistication of their computer.
GitHub repositories: https://github.com/MarkMLl?tab=repositories

MarkMLl

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Re: WriteLn and DOSBox
« Reply #18 on: July 03, 2021, 01:43:05 pm »
That's actually quite interesting ... and rather baffling, since the IDE has been working quite well till now and the only piece I can think of having to bear with this would be the Bosch (virtual) VGA BIOS, and that's a really mature and optimized piece of software. The other thing it might be would be the VGA emulation, but those are also rather mature and well understood. I would love to have the time to investigate this more fully, sounds interesting; unfortunately I haven't got it :(

I wonder why the Bochs manual has this, with no further explanation?

"6.3 Text-mode is broken in some ancient DOS program"

https://bochs.sourceforge.io/doc/docbook/user/textmode-problems.html

MarkMLl
MT+86 & Turbo Pascal v1 on CCP/M-86, multitasking with LAN & graphics in 128Kb.
Pet hate: people who boast about the size and sophistication of their computer.
GitHub repositories: https://github.com/MarkMLl?tab=repositories

lucamar

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Re: WriteLn and DOSBox
« Reply #19 on: July 03, 2021, 02:19:05 pm »
I wonder why the Bochs manual has this, with no further explanation?

"6.3 Text-mode is broken in some ancient DOS program"

https://bochs.sourceforge.io/doc/docbook/user/textmode-problems.html

Probably because lots of EGA/VGA/SVGA clones BIOSes (nevermind the hardware itself) were quite buggy so as soon as you tried something "esoteric" like, for example, change the number of lines (e.g. to 28/30 or 50/60 lines) all kinds of mayhem might ensue: characters chopped off, cursor mishaps, vsync going bonkers, etc.

I wrote a program to do precisely that (change the lines to one of twelve modes) and it's full of kluges to deal with those bugs, along with a long list of cards/chipsets/BIOSes with some problem or other and whether they could be worked around somehow.
« Last Edit: July 03, 2021, 02:20:46 pm by lucamar »
Turbo Pascal 3 CP/M - Amstrad PCW 8256 (512 KB !!!) :P
Lazarus/FPC 2.0.8/3.0.4 & 2.0.12/3.2.0 - 32/64 bits on:
(K|L|X)Ubuntu 12..18, Windows XP, 7, 10 and various DOSes.

Anon1024

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Re: WriteLn and DOSBox
« Reply #20 on: February 12, 2022, 07:56:09 am »
Just adding some info to fully resolve/explain this issue.

The WriteLn issue is (almost certainly) not due to a bug in FPC; it is due to a bug in DOSBox.

To test, I used the FPC installer for DOS. There was no special reason to use the FPC installer; I only used it because I noticed the strange display issues when I had previously tried running it under DOSBox.

The installer displayed fine on:
    * FreeDOS 1.2 running under QEMU
    * FreeDOS 1.3 running under Bochs 2.7
    * DOSBox-X v0.83.22

The installer did not display fine on DOSBox (v0.74-3). If interested, see the attachment, 'install.png' which shows another example of what other people have described.

Interestingly, there seems to be a deeper issue with DOSBox which may be related to the screen corruption issue. In DOSBox, when INSTALL.EXE was run, it could not find the INSTALL.DAT file. (The error is shown in the attachment.) Both files reside in the same directory. The exact same directory was used with DOSBox-X and it worked fine.

Cheers!

Ñuño_Martínez

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Re: WriteLn and DOSBox
« Reply #21 on: April 16, 2022, 06:40:25 pm »
AFAIK FreeDOS uses some code from DOSbox so maybe that's why both have the same behavior.
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