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The 286 chip wasn't around for long, but there should have been some software or OSes made for it?

Basically, i'm looking for whatever information there is on 286, with the intention of developing the 286 emulation in my EPC emulator.

Perfect would be assembler tutorials for 286 pmode or set of CPU tests, good would be open source (or small enough to disassemble) software or hobby OS for it, nice to have would be anything that is known to use 286 in a reproducible manner.

Windows 3.0 is not good at this point - it does something deep inside that i can't get at.
himem.sys is borderline - i can't get it to go into pmode. Some usage examples, maybe.
286 bios sources you can google were made with OCR software, and as such are quite useless, if only for reference.

So, does anyone have or know where to get something of that description?

286-specific assembly is relatively rare since the 286 was a pretty bad device to make optimisations for.

Does regular 16-bit code work? You can try to run DOS with Turbo C++ 3.0 which has an option to create 286-specific code so you can actually generate apps for the 286 or different systems. Of course, being able to run DOS inside your emulator is pretty much a good stability test before trying 286 protected mode.

There were several Unix systems related for the 286 which had a primitive form of protected mode, Minix2/Coherent3/Xenix.

I believe releases of OS/2 and Windows took advantage of it as well.

I'm sure there was a lot of commercial DOS software that used 286 features, no doubt you'll be able to find something.

Combuster wrote:Does regular 16-bit code work? You can try to run DOS with Turbo C++ 3.0 which has an option to create 286-specific code so you can actually generate apps for the 286 or different systems. Of course, being able to run DOS inside your emulator is pretty much a good stability test before trying 286 protected mode.

The emul is stable enough to run DOS, windows 3.0, xenix, and lots of contemporary software, so no problems there.

Quick try on TC3 revealed that it needs 286 as well to run. But, it works in DOSbox.
Unfortunately, simple programs compiled with 80286 option work as well. I guess it's only about memory use or something like that, the code is pretty much the same as with 80186 option, with a couple bytes added.

Brynet-Inc wrote:I'm sure there was a lot of commercial DOS software that used 286 features, no doubt you'll be able to find something.

Sure, commercial. The mentioned TurboC++ 3.0 uses it, but gives DPMI errors. Something is not right, and where to track it i have no idea. Windows 3.0 uses it as well, but it starts calling opsize in the middle of nowhere and i can't even find where to look.
That's why i'm looking for something simple, like assembler tutorials or cpu tests.

Artlav wrote: Perfect would be assembler tutorials for 286 pmode or set of CPU tests, good would be open source (or small enough to disassemble) software or hobby OS for it, nice to have would be anything that is known to use 286 in a reproducible manner.

That's sad, I just looked over at my book shelf and there is '8086/8088/80286 Assembly Language by Leo Scanlon'. If you do a search for '80286 shareware' you will get lots of hits, there were lots of bbs's with lots of shareware at that time.