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Date:      Mon, 15 May 2006 10:27:00 +1000
From:      "Murray Taylor" <MTaylor@bytecraft.com.au>
To:        "Jim Thompson" <jim@netgate.com>, <gnn@freebsd.org>
Cc:        minibsd@ultradesic.com, freebsd-small@freebsd.org, mk@neon1.net
Subject:   RE: Embedded FreeBSD Presentation...
Message-ID:  <04E232FDCD9FBE43857F7066CAD3C0F117CA31@svmailmel.bytecraft.internal>

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George, Jim et al,

Have you looked at the miniBSD build system
described below? =20

I just ran an 'embedded' system during the=20
2006 Melbourne Commonwealth Games to monitor the
lighting system datanet that was

Freebsd 4.11 based, handled SNMP trap monitoring, fping monitoring,
SNMP fetch queries and SMS notifications.

I had a DHCP server running on the main LAN, dhclient on the WAN port,
sshd login and about 60-70 of the basic programs
(vi, awk, more, grep, find, sh, csh, gsmsmsd... ) fully available to me.
All managed within a couple of shell scripts and a cron job or two.

Hardware: 300MHz 486, 32 Meg RM, and a 32 MEG CF flash disk.
kernel was minimally downsized by removal of unneeded functions,
and was loaded on the flash disk as kernel.gz, to be ungzipped=20
automagically during boot. All other programs had been rebuilt
to use dynamic libraries rather than static linkages to reduce the
binary sizes.

CF space used
=09boot partition: approx 22 Meg of 28Meg
=09config data partition: approx 20 Kilobytes of 4 Meg

NB Config data actually was all the shell scripts and my=20
.conf files. Done this way so that the config partition=20
could be mouunted R/W during shutdown to save all shell scripts
and config data that may have been edited / updated since boot.

Original minibsd
Freebsd 4.7 -> 4.11	https://neon1.net/misc/minibsd.html
and derived works
Freebsd 5.x
http://www.ultradesic.com/index.php?section=3D86
Freebsd 6.x
http://www.ultradesic.com/index.php?section=3D125

I didnt do the original work, I just use it, and it is a blast.
Particularly useful is keeping a dnode mounted disk image of
the CF on the development host. Dead easy to copy new programs to
the vnode mount, unmount it, dd a new CF image, and run. Also
by temporarily mounting the miniBSD boot partition as R/W, one can
do a SCP copy of a file to the CF disk from the development host
over the WAN ....

Useful, you betcha!


Murray Taylor

Special Projects Engineer
Bytecraft Systems

P: +61 3 8710 2555
F: +61 3 8710 2599
D: +61 3 9238 4275
E: mtaylor@bytecraft.com.au=20

--
"Any intelligent fool can make things bigger and more complex... It
takes a
touch of genius - and a lot of courage to move in the opposite
direction."
=20 Albert Einstein=20
--=20

> -----Original Message-----
> From: owner-freebsd-small@freebsd.org=20
> [mailto:owner-freebsd-small@freebsd.org] On Behalf Of Jim Thompson
> Sent: Monday, 15 May 2006 6:56 AM
> To: gnn@freebsd.org
> Cc: freebsd-small@freebsd.org
> Subject: Re: Embedded FreeBSD Presentation...
>=20
>=20
> On May 14, 2006, at 5:45 AM, gnn@freebsd.org wrote:
>=20
> > At Sun, 14 May 2006 09:16:48 +0200,
> > Eduardo wrote:
> >> Is this really possible:? Sorry for be a bit unoptimist,=20
> but in the=20
> >> embeded space the o.s.must follow some rules that freebsd=20
> (nor linux,=20
> >> *bsd, windows, etc..) can't:
> >>
> >> - size: The o.s. must be minimal. Freebsd kernel, now, is=20
> a bit huge.
> >> - realtime: The o.s. must do some tasks at fixed times, this tasks=20
> >> can't wait for nothing.
> >>
> >> The size one can be fixed, but the realtime not. It needs a new=20
> >> scheleude, irq manager,...; so a great kernel rework.
> >
> > Perhaps you mis-understand the thrust of this drive, in that we are=20
> > not talking about turning FreeBSD into an RTOS, at least not in the=20
> > short term, but about making it more amenable to embedded.
> >
> > There is much to do but it will be a gradual process.  Size and=20
> > configuration are the first things to address.
> >
> >> Also, you forget the PowerPC chips. They are in a lot of embedded=20
> >> devices and now freebsd has support for them (6.x).
> >
> > We did not forget them but amongst those who have shown interest in=20
> > this project ARM and MIPS are the clear leaders.  If we find people=20
> > who wish to address the PowerPC chips as well, all the better.  One=20
> > other important component in this work is focus.  We cannot be all=20
> > things to all people, at least not at the outset, so two different=20
> > processors and two or three reference boards for each are where we=20
> > plan to start.
>=20
> In the embedded world, most people who build their own "SOC"=20
> tend to use ARM7, ARM9 or MIPS cores.
> For instance, Atheros and Broadcom both use a MIPS 4KC core in their =20
> WiFi parts.   Realtek uses an LX50 core, which is "MIPS minus the =20
> patented instructions" (there is a port of GCC which won't=20
> issue these instructions).
>=20
> TI uses ARM7 in OMAP, but that platform is probably "too=20
> small" for FreeBSD's resource requirements in the immediate=20
> future.  (Read: lots of work to squeeze FreeBSD onto=20
> platforms using OMAP.)
>=20
> Folks who are not ODMs of one of these companies tend to use PowerPC =20
> (either IBM's 440 or one of the Freescale parts) or Xscale.   Intel =20
> did a real "number" on the market starting in 2003 (similar=20
> to what they did to the WiFi chip market with Centrino) and=20
> essentially drove suppliers of MIPS core parts (such as IDT)=20
> into a corner of the market.
>=20
> That said, there are very few "commodity priced" PowerPC boards.
>=20
> I think the most "bang for the buck" will be found porting=20
> FreeBSD to Xscale (especially the ixp42x parts) first,=20
> followed by PowerPC (because FreeBSD is already running on a=20
> (slightly different) PowerPC chipset), and then the various=20
> MIPS-based parts that support WiFi or the little=20
> switches-with-embedded-MIPS parts.
>=20
> Jim
> _______________________________________________
> freebsd-small@freebsd.org mailing list
> http://lists.freebsd.org/mailman/listinfo/freebsd-small
> To unsubscribe, send any mail to=20
> "freebsd-small-unsubscribe@freebsd.org"
>=20
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>=20
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