Contemplating the 80186 (Was: Open questions in OS design)

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Troy Martin
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Re: Open questions in OS design?

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berkus wrote:Wow, are you guys really coding for the 80186??! Wow!
I am, I feel like coding for a minimal configuration is a good, fun challenge.

EDIT: and pulling a UD2 is fun :P
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Solar wrote:It keeps stunning me how friendly we - as a community - are towards people who start programming "their first OS" who don't even have a solid understanding of pointers, their compiler, or how a OS is structured.
I wish I could add more tex
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Re: Open questions in OS design?

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It's one of those strange gifts. The most important part of it was POPA and PUSHA.
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Solar wrote:It keeps stunning me how friendly we - as a community - are towards people who start programming "their first OS" who don't even have a solid understanding of pointers, their compiler, or how a OS is structured.
I wish I could add more tex
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Re: Open questions in OS design?

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Troy Martin wrote:The most important part of it was POPA and PUSHA.
Which can be simply simulated on a 8086 and its even faster to do so. :roll:
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Re: Open questions in OS design?

Post by jal »

berkus wrote:Nice, I've never seen a 80186 in real life. 8086 and 80286 yes, but never a 80186 :(
The 80186 was used mostly in embedded systems, as it includes a PIC, PIT etc. on-dye. I've seen them used in ECRs, for example (the TEC FT-77, to be precise).


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Re: Open questions in OS design?

Post by jal »

cyr1x wrote:
Troy Martin wrote:The most important part of it was POPA and PUSHA.
Which can be simply simulated on a 8086 and its even faster to do so. :roll:
No it's not. In raw clock cycles yes, but don't forget instruction fetching.


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Re: Open questions in OS design?

Post by Colonel Kernel »

How did a discussion about the frontiers of OS design & theory become a discussion about a nearly 30-year-old CPU? :lol:
Top three reasons why my OS project died:
  1. Too much overtime at work
  2. Got married
  3. My brain got stuck in an infinite loop while trying to design the memory manager
Don't let this happen to you!
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Re: Open questions in OS design?

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No future without a past, I guess :wink:
Topic split, go bump it if you want.
"Certainly avoid yourself. He is a newbie and might not realize it. You'll hate his code deeply a few years down the road." - Sortie
[ My OS ] [ VDisk/SFS ]
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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by Troy Martin »

The 186 is only 25-ish years old, was first produced in 1982. Still, it's fun to program for it!
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Solar wrote:It keeps stunning me how friendly we - as a community - are towards people who start programming "their first OS" who don't even have a solid understanding of pointers, their compiler, or how a OS is structured.
I wish I could add more tex
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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by jal »

Troy Martin wrote:The 186 is only 25-ish years old, was first produced in 1982. Still, it's fun to program for it!
Do you actually own one (or several)? What type of hardware is it? Ordinary PC-clone?


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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by Troy Martin »

I don't own a box with one (they weren't widely known, as you can see here) mostly because they were for the embedded market IIRC.
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Solar wrote:It keeps stunning me how friendly we - as a community - are towards people who start programming "their first OS" who don't even have a solid understanding of pointers, their compiler, or how a OS is structured.
I wish I could add more tex
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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by jal »

Troy Martin wrote:I don't own a box with one (they weren't widely known, as you can see here) mostly because they were for the embedded market IIRC.
So how do you test? Or do you just use modern hardware?


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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by Troy Martin »

I just use modern hardware but I like restricting it so that someone with a box from 1984 can use my OS.

Edit: Alex, how did you get that font for your graphics mode?
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Solar wrote:It keeps stunning me how friendly we - as a community - are towards people who start programming "their first OS" who don't even have a solid understanding of pointers, their compiler, or how a OS is structured.
I wish I could add more tex
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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by jal »

Troy Martin wrote:I just use modern hardware but I like restricting it so that someone with a box from 1984 can use my OS.
But they can't, can they? Noone had a 186, so you effectively target 286 boxes. Which were available/affordale from 87/88. Why not target the 8086/88? Then I'd at least be able to run it on my XT :). Also, the hardware from that era is quite different from the current, no IDE etc. I'm even not sure whether INT 13 was available for those old MFM harddisks (ST-157A FTW :)).


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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by abachler »

jal wrote:
Troy Martin wrote:I just use modern hardware but I like restricting it so that someone with a box from 1984 can use my OS.
But they can't, can they? Noone had a 186, so you effectively target 286 boxes. Which were available/affordale from 87/88. Why not target the 8086/88? Then I'd at least be able to run it on my XT :). Also, the hardware from that era is quite different from the current, no IDE etc. I'm even not sure whether INT 13 was available for those old MFM harddisks (ST-157A FTW :)).


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According to Ralph Brown's 'PC Interrupts' INT 13 and most of its sub functions are available for 'All Machines'.
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Re: Contemplating the 80186 (Was: Open questions in OS design)

Post by jal »

abachler wrote:According to Ralph Brown's 'PC Interrupts' INT 13 and most of its sub functions are available for 'All Machines'.
Yes, a quick google turns up this page which has some more information.


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