Dos Port

[jmetal88]

Hi, I found this open source DOS project that's supposed to have at least some level of compatibility with real DOS. I figured since it was possible to port Linux to GP, maybe someone could work on porting this. The sourceforge page: http://freedos.sourceforge.net/.

 

[loki666]

no way!
Linux was ported to GP32 because linux IS portable.
FreeDOS isn't portable at all, its aimed for x86 only

 

[lizard808uk]

Is it possible to strip down either Castaway or MSX emulators to only just run DOS (so it becomes an interpreter) and then optimise the pants out of it so its really fast? [DOS is available for both systems] Is the x86 thing a really important part of DOS, and is it necessary?

I know this sounds like I'm talking BS, (I guess I probably am) but would love to one day see Colonization for my favourite handheld.

 

[Vimacs]

you have no chance to "interpret" dos in a way that it can run any old msdos games on gp couse we use a arm and msdos is designd for x86.
the only way would be to emulate a complete x86pc, like dosbox do. but that would be veeeeery slow, we would end up with under 10mhz x86 i think.
so it isnt worth the work.

 

[Mark1970]

Is it possible to strip down either Castaway or MSX emulators to only just run DOS (so it becomes an interpreter) and then optimise the pants out of it so its really fast? [DOS is available for both systems] Is the x86 thing a really important part of DOS, and is it necessary?

I know this sounds like I'm talking BS, (I guess I probably am) but would love to one day see Colonization for my favourite handheld.

​

DOS for pc's is an operating system that is closely involved with the hardware of the machine it is running on. There's no hardware abstraction layers at all, just a whole bunch of routines closely interacting with the system's bios, cpu, graphics card and ram, and the user interface is limited to something called command.com (or a replacement) which is an interface for accepting commands from the command line. It's called a disk operating system, but some would call it a 'dirty operating system'.

Without providing the hardware that DOS expects, DOS will not function at all. Since there is no PC bios inside the GP32 nor is there a x86 compatible CPU or other pc components, DOS will not function. That's the reason why a macintosh or atari ST will not boot ms-dos. It doesn't have the hardware needed to run DOS.

The opensource freeDOS OS functions in a similar way, also colosely involved with the pc's hardware & bios albeit programmed/designed much nicer. You'll need a pc compatible machine in order to run it.

When you want to run something like DOS on the gp32 this can only be achieved by emulating the pc's hardware neccessary together with some sort of pc compatible BIOS-layer for DOS to run.

 

[lizard808uk]

Fair enough. To sum up ARM -> x86 DOS = Impossible.

 

[Shirohagen]

Nooooooo!

Colonization MUST be achieved!

®

 

[jmetal88]

Well, I was just wonderin' 'cause it says something on freedos.org about it running on portables, but I couldn't find a link to that source code...... forgive my programming stupidness, please.

 

[MegatronUK]

FreeDos is an open-source implementation of MS-Dos... think of it along the lines of a free alternative that runs on the same hardware and is mostly compatible (ie you can run the same games, utilities etc.).. it is NOT an emulator for Dos.

Normal MS-Dos works like this:

PC hardware (cpu, soundcard, gfx etc.)-> BIOS -> Dos (MS-Dos/Freedos/Epson-Dos/DR-Dos) -> Games (Doom, Star Control, Civ, whatever..)

For Dos and games to work on the GP32 the following sequence would have to take place:

PC-Emulator -> Emulated PC hardware -> Emulated PC BIOS -> Dos (MS-Dos/Freedos/Epson-Dos/DR-Dos) -> Games

It's not impossible at all, in fact its technically possible to do it right now (run Bochs, which emulates PC-hardware and provides an emulated PC-BIOS) on top of the GP32 Linux port (you would then install MS-Dos or one of the compatible on top of that, then run your dos games on that). However, it would be EXTREMELY slow and very memory limited (bear in mind, each stage of the process [linux, bochs, dos, game] takes a chunk of memory out of the GP's 8mb), to the point of being absolutely unuseable.

 

[Rigor Mortis]

The PC/DOS emulator Bhole is being ported to Dreamcast and apparetnly already runs some games, maybe someone could check it out. After all, DOS on Dreamcast was also "impossible".

 

[jmetal88]

And I just got my Dreamcast.... Sweet!