From: acahalan@gmail.com (Albert Cahalan)
Subject: [TUHS] Redoing "V6on286" or porting V7...?
Date: Sat, 12 Nov 2005 01:13:47 -0500 [thread overview]
Message-ID: <787b0d920511112213q7156614cv2fe3c5d00852f45c@mail.gmail.com> (raw)
In-Reply-To: <849b04683754b84f7e42810d761db3bd@coraid.com>
On 11/9/05, Brantley Coile <brantley at coraid.com> wrote:
> my suggestions are as follows (i assume you really mean 8086 mode):
That wouldn't be a good match. I believe you want this:
* 16-bit
* protected mode
* no paging
* 8 or 16 segments
* 128 kB of the memory
* no FPU
> using a floppy to boot is a great idea. i've written several boot
> straps to boot from the floppy that configure the serial port, and put
> the processor in 32-bit mode. it's tight, but not too hard. you have
> a great advantage in that you're going to stick to 16 bit so you can
> use the bios. 512 bytes in that case is tons of space.
512 is easy until you try to handle more than one machine. :-(
> next you'll need to write device drivers for the screen/keyboard, the
> clock, and the floppy. later you can write an ATA driver and get a
> mbr and hard disk boot strap.
I think you need a 4 MB disk and a 10 MB disk. :-)
> if you want to do a 32-bit version, then things are a little
> different. but this should give you the v6 in about as little
> work as can be.
You might use a 32-bit CPU in 16-bit mode. Then you could use
a 32-bit limit on the FS or GS segment for easier physical memory
access from the kernel. (use an opcode prefix as needed)
next prev parent reply other threads:[~2005-11-12 6:13 UTC|newest]
Thread overview: 18+ messages / expand[flat|nested] mbox.gz Atom feed top
2005-11-09 17:26 Lyrical Nanoha
2005-11-09 21:54 ` M. Warner Losh
2005-11-09 22:03 ` Brantley Coile
2005-11-12 6:13 ` Albert Cahalan [this message]
2005-11-12 13:18 ` Brantley Coile
2005-11-13 20:16 ` Peter Jeremy
2005-11-14 9:38 ` Wesley Parish
2005-11-14 15:45 ` Brantley Coile
[not found] ` <8a61b612cf43394f33e6531339fe4263@coraid.com>
2005-11-14 19:49 ` Peter Jeremy
2005-11-14 20:31 ` Brantley Coile
2005-11-16 21:41 ` Lyrical Nanoha
[not found] ` <17277.62390.986234.433543@hod.localdomain>
2005-11-18 17:59 ` Lyrical Nanoha
2005-11-19 4:17 ` Brantley Coile
2005-11-15 3:08 ` Greg Haerr
2005-11-15 3:40 ` Peter Jeremy
2005-11-15 13:30 ` Brantley Coile
2005-11-14 21:34 Norman Wilson
2005-11-14 22:59 ` Brantley Coile
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